We are big fans of SPDIF converters around these parts. All USB DAC's have SPDIF converters inside them anyway so why do some folks refuse to use them? Simplicity is the answer but don't let that stop you from giving them a shot. These converters allow you to switch DAC's in and out of your rack as fast as you can physically unhook your cables to your device. This is very useful when reviewing DAC's or doing quick comparisons between equipment. We've noticed no loss in sound quality when we place a SPDIF in the chain versus going straight USB into a DAC.

We finally got our hands on the famous Berkeley Audio Alpha USB and we've got some photos of it topless for all those folks who are wondering what's under the hood. The Alpha seems pretty light when we first placed it in our hands. For some reason, we were expecting it to be heavier after looking at it online and in various magazines. I don't feel a component has to be heavy to sound great but it's just one of those things I suppose us audiophiles look for. The other random thing that caught my attention when looking over our Alpha was that it did not contain a power switch to turn the unit on or off. It stays on when plugged in and the LED on the front panel turns from orange to green when a USB signal is present. This keeps the Alpha warmed up and ready to go at all times.

When we removed the top cover we noticed the 2"x2" plastic plate the USB input jack was mounted to as well as the extra shielding between the USB input section and the AES/ BNC digital output section on the circuit board. This close attention to detail must have resulted in better performance and subsequently resulted in the highest price tag of any SPDIF converter we've seen to date. We were eager to get the Alpha set up and playing as we've heard around the campfire that this little bugger sounds amazing. Verifying this gossip was important for not just us but for any potential buyers out there.

Well, setting the Alpha up was basic and involved plugging the unit in to our HD Ref-3 server and installing the Windows 7 driver. The driver is the standard Thesycon TUSB driver which is used in conjunction with the XMOS USB input chip which the Alpha utilizes. We really like the Thesycon drivers as they have embedded ASIO support so setting up Album Player was an absolute piece of cake. After a few tweaks to the TUSB buffer settings and uninstalling our previous Thesycon device drivers, we were on our way.

We ran the Alpha USB in for 24 hours to make sure it was warm and then we gave it our usual listening test. (The unit was previously broken-in before we received it) We played all digital file formats successfully from 16.44 all the way up to 24.192 with no issues. The product manual states WASAPI should be implemented along with Foobar or JRiver but we went with ASIO and Album Player and we had no issues with playback what so ever.

Wow, this does sound slightly better than the M2Tech EVO (without the external clock option) and any other SPDIF converter for that matter that we've tried!!! I guess it better considering it's hefty $1900 MSRP. We noticed slightly more detail and a nicer soundstage as well as an overall "tighter" or "more together" sound. That's not a good description but we don't know how else to describe it. Everything just sounded right. The difference between the M2Tech EVO and the Alpha was not night and day by any means but there was a discernible difference none the less. The law of diminishing returns comes into play here.

So, it turns out the current reviews out there are correct. The Alpha is the king when it comes to SPDIF converters and if you're willing to pay for it, you'll be rewarded with some of the best sound we feel is possible from any SPDIF converter. Well, that's disregarding maybe Empirical Audio's Off-Ramp SPDIF converters or the latest Audiophilleo SDPIF converters with Pure Power? Or maybe the entire M2Tech EVO 'Complete Stack' takes the cake? We haven't got our hands on all of these yet but we're keeping them in mind. We're enjoying the Alpha especially as a way to switch between two DAC's for comparisons and we're going to hate to see this one leave the YFS listening room. All good things must come to end sometime, right? Well not if we want to fork over some serious cash. Maybe some time down the road but not now as we've got more pressing matters...

-YFS Design Team


Associated Equipment:

  • YFS HD Ref-3 SE Music Server Transport
  • Eastern Electric Minimax DAC Plus
  • Bricasti Design M1 DAC
  • Jolida Glass FX MkII DAC
  • YFS Custom Ca-60 Preamp
  • McIntosh MC275 MkV Amplifiers (In mono configuration)
  • Von Schweikert VR-44 Aktive Speakers
  • PS Audio Power Plant Premier (one for each monoblock)
  • Equitech 1.5Q Balanced Power Isolation Transformer (used for source components)
  • YFS Cabling and Interconnects


by Kevin OBrien on October 15th, 2012


We made it out to Riverside, CA to visit the VSA factory to give Albert and Damon a demo of our YFS Ref-3 SE music server. The trip gave us a chance to hear some fantastic speakers and other gear including the Audio Research DAC8 USB Digital to Analog Converter. We wanted to let folks know about our general thoughts and opinions on this interesting USB DAC.

We were able to install the ARC DAC8 drivers without any problems but we ran into some small snags after we were up and running. We could get every file we played to output perfectly except 24.192. We're not sure what the exact problem was but we're confident if we got the DAC back to our listening room in Rochester, we'd be able to get it figured out. We didn't like their drivers in terms of all the options we had to choose from. We've used the Thesycon USB drivers previously but for some reason the ARC drivers were a little different. (More than just the fact that the little red "T" was replaced by the "ARC" symbol in the system tray) Some of the buffering options and file format output options started to get a little frustrating especially when you factor in how many combinations one can choose from while trying to dial in the USB input settings. The main comment we have that we'd like ARC to pay attention to when designing their next DAC iteration is to include a bypass-able volume control and leave the Thesycon drivers alone. Let Thesycon do their job and you guys do yours. USB software and USB hardware are two entirely different areas. We feel Thesycon has it covered for now. Don't fix it if it ain't broken, right?

The XMOS USB input software includes its own ASIO drivers and we like that. Unfortunately, ARC took it to the next level by modifying the basic TUSB software and we think they may have turned an easy-to-use software driver into a little more difficult driver than we'd like to see. We've noted other folks having some difficulty with getting hi-res files to work as well so we'd really like another shot at getting the DAC8 to work perfectly with our Ref-3 server. Maybe we can convince the head of equipment acquisition at VSA to send it out to us for one more shot? We'll see...

We eventually bypassed the USB input by hooking up an M2Tech EVO that was laying around and we tested the XLR and COAX inputs which passed 16.44 all the way up to 24.192 with absolutely no problems at all! Nice work ARC. We've tried using SPDIF converters in the past with DAC's and we've run into incompatibility issues especially regarding 24.176 and 24.192 file formats. A lot of equipment specs say their specific DAC can handle those two formats when in reality they cannot.

The DAC8 is well built and has the classic ARC look with a silver or black faceplate with their signature handles to compliment the utilitarian look. It weighs in at a just under 12 lbs so it isn't the heaviest DAC we've moved around but not the lightest either. We were definitely digging its looks in Albert's rack. We were hooking up to the silver unit in our case and it matched really well with the rest of the gear. We particularly liked the indicator lights on the front of the DAC that told us which sample rate we were currently using from 44.1 up to 192 including 176.4. That's a nice touch especially when you're wondering if you're playing the redbook or the hi-res version of an album while you're comparing the two.

Most importantly, the DAC8 sounded great. It reminded us of a tube DAC with that extra bit of dynamic range and less distortion than a tube solution. NICE JOB ARC! If you're looking for that laid back sound with great bass and mids without the sometimes edgy solid state highs, this is the DAC for you. Again, we could have sworn there were tubes in there somewhere!

Aside from the tweaked Thesycon drivers and not being able to get full compatibility with all the accepted hi-res digital formats, we loved the ARC DAC8 (the latter could have also had to do with our lack of set up time). We have a feeling if one were able to score the DAC8 on the used market for a good price, it would be well advised and a great pick-up. All in all, we really enjoyed the sound and the build quality of the DAC8. The next ARC DAC8 iteration should be a little friendlier as far as setup goes and a volume control would be helpful. Being able to totally defeat that volume control would be even handier and a welcome change to what otherwise is a real winner.

Until next time...

-YFS Design Team


Associated Equipment:

  • YFS HD Ref-3 SE Music Server Transport
  • YFS Custom Ca-60 Preamp
  • McIntosh MC275 MkV Amplifiers (in mono configuration)
  • Von Schweikert VR-44 Aktive Speakers
  • PS Audio Power Plant Premier (one for each monoblock)
  • Equitech 1.5Q Balanced Power Isolation Transformer (used for source components)
  • YFS Cabling and Interconnects


by Kevin OBrien on 04/21/2012


I decided to give my Eastern Electric Minimax DAC Plus an anabolic shot in the keyster a couple days ago. One quick and easy tweak you can apply to this DAC is changing out the operational amplifiers (op amps) to get a different sound. This is an option because Alex Yeung used sockets for the op amps instead of soldering them in like most other designers do. THANKS Alex!

A VERY helpful company based out of Oklahoma, Cimarron Technology, helped make this possible. They offer very handy adapters that allow you to drop in replacement op amps without the need to solder them onto the adapters yourself! I am specifically referring to the "SO8 to 8-pin DIP Adapter" that they offer for $3. They give the user several options for pre-mounted op amps such as the LME49990, OPA627AU, OPA2604, OPA827AI, AD8397, and the OPA2134 to name a few.

Alex, the designer of the Minimax DAC and DAC Plus, has approved these for use with both the DAC and DAC Plus. This voids the warranty but I'm not too worried about that. I've played the unit for over 8 months with absolutely no issues so I figured I'd just go for it and I'm glad I did.

According to Bill O'Connell of Morningstar Audio, the op amp rolling can make a nice improvement. He offers the combination that I have tried pre-installed for an extra $100 over the retail price of the DAC Plus. This way you can retain the warranty if that is important to you. You can save $20 by doing it yourself. I obviously opted to do it myself. The op amps are plug and play so there's really not much you can do wrong as long as you're careful.

I ended up going with the OPA2604 in the U1 and U2 positions. If the user is only interested in the tube output, he can choose to replace only the U1 and U2 op amps as the U6 and U7 op amps are used for the solid state output. I also ordered the OPA827 for positions U6 and U7. One quick note here: If you plan on ordering the above mentioned combination you have to order (2) of each op amp pre-soldered onto the "SO8 to 8-pin Adapter".

Do NOT order any other adapter board combination. There are a couple more options such as the Burson Audio HD Op Amps as well as the NewclassD Dexa Dual 73728 and Dexa Single 73729. Both sets of op amps can be had from Parts Connexion. Folks have reported that a combination of Dexa's and Burson's can really take the DAC Plus to a new level but the price tag is a little steep. The Dexa combo (4 op amps) will run you $280 and the Burson combo (4 op amps) comes to $295!!! OUCH! Most users agree that the 2604/ 827 combo is the way to go for $80. If you're on a budget like I am, it's DEFINITELY the way to go. One caveat here: If you are using the latter op amp combo (Dexas or Bursons), the cover of the DAC Plus will not fit on top of the unit. You most likely will have to space the cover from the chassis with spacers and longer screws or something to that effect.

I figured it would be nice to try the solid state output of the DAC Plus with the tube removed just for fun. I'm glad I tried this. There seemed to be a bit more detail in the SS mode so I chose to keep the DAC Plus in that mode. I can alter the presentation of the music by switching my preamp tubes to GE 12AX7's from my current Siemens 12AX7's if things get a little too bright so I wasn't worried.

The op amp rolling results were pretty interesting. I noticed more detail/ separation and more punch in the low end. This was just what Bill had reported during his op amp rolling sessions. VERY COOL!  I could definitely hear more detail and the instruments seemed that much easier to identify as they felt like they were in their own space.

I ran the op amps in for 100 hours just to make sure before I did any critical listening. There seems to be some debate on whether "burn-in" is real or just a phenomenon. I am definitely a believer in burn-in. That is an entirely different discussion for another time.

I hope I've shed some light on what your options are for rolling op amps in the Minimax DAC and DAC Plus. It's as easy as popping off the cover, removing the original equipment, and then placing the new op amps in their place. Make sure you place them in the sockets facing the correct way and you're good to go.  That's about the only thing you need to pay close attention to as well as not discharging any static electricity into your DAC's internal components. Again, if you're not comfortable with this process, Bill will pre-install the 2604's and 827's for a $20 charge over the cost of the parts. THANKS Bill!

Until next time...



Associated Equipment For This Review:

  • HD Reference-2 Computer Music Server
  • Quicksilver 12AX7 Tube Preamp
  • McIntosh MC275 Tube Power Amp
  • Von Schweikert VR5 HSE Speakers
  • YFS Custom Litz Speaker Cables
  • YFS USB Reference V1 Custom USB 2.0 Cable Prototype
  • YFS Custom Room Treatment
  • YFS Custom Interconnects
  • YFS Custom Power Cables


by Kevin OBrien on March 19, 2012


We figured enough folks would have an interest so we checked it out. We used the same set-up within the "IBM T43 vs. Theta Carmen II" review so you can check that out here. We ended up using a DELL Latitude D510 as our other computer source. It has essentially the same specs as the IBM T43 so we could keep things fair (we added a 150 GB HDD, 512 MB of RAM (1 GB total), and it has a 1.87 GHz processor). Foobar 2000 was the digital player on both computers. We used the Silnote Audio Poseidon USB cable plugged into the M2Tech EVO from the IBM T43. We then used the Veloce 75 Ohm Black Cat Digital BNC cable to go from the M2Tech EVO to the Minimax DAC Plus. We used an ACR Reference Silver USB cable out of the DELL plugged directly into the same Minimax DAC Plus' USB input. Another important point to note is that the M2Tech EVO USB converter is essentially buried within the Minimax DAC Plus chassis, external PS aside. It's really more like the HiFace is inside the DAC chassis but you get our basic point. We definitely thought it would be an interesting shoot-out. We would be toggling between the two set-ups via the input switch on the Minimax DAC Plus.

Just a small note to the reader here first. We have compared the ACR Silver Reference USB to the Silnote Audio Poseidon USB and they are practically identical in sound quality! (neither cable is available today unfortunately) I wanted to let the readers know we are keeping the comparison as fair as possible. We feel here at YFS that the USB interface is the most preferable way to hook up your digital source to a DAC. Why do we say that? Look at the trouble we've had trying to get digital 24.192 signals through a COAX digital BNC cable to a DAC! None of our USB cables have had ANY trouble sending that signal to a DAC. You decide for yourself. (We think it's even better than firewire) Sorry to get sidetracked.

Now that you are familiar with the equipment and what we are trying to achieve, let's describe the results. We did an A-B comparison with both set-ups and we could not hear a difference! I know that different USB cables are involved in the test but we tested those out independently of this test and we feel they're both extremely similar. Both computers are essentially the same although the IBM has more RAM. We are using a legit digital COAX cable as well so we feel those are not the main factors in the test.

Adding the SPDIF converter and the BNC cable had no effect on sound quality. It neither added, nor subtracted from what was going on. The only difference by going DIRECTLY into the USB input was that we could now enjoy 24.192 and 24.176 digital files without any upsampling or downsampling. VERY SWEET!

What's the lesson here you say?

If you need to use a USB to SPDIF converter, don't be afraid of degrading your system's sound quality. Although there is a plus to using a straight USB digital signal into your DAC, it's not a deal breaker if you're happy with the resolution (24.96) you're getting out of your digital COAX cable!

Thanks for reading and enjoy!



Associated Equipment for this Review:

  • Eastern Electric Minimax DAC PLUS
  • YFS/ SCH Custom Speakers
  • YFS Custom Room Treatment
  • YFS Custom CA-60a Preamp and Custom 6L6 Tube Power Amp
  • YFS Custom Interconnects and Cables


by Brad Easton and Kevin OBrien on 03/08/2012


We recently decided to upgrade from our Musical Fidelity V-DAC to the newer V-DAC MkII. We'd like to let our readers know about the main differences between the two in case anybody is in the market for the new version. We paired the older V-DAC with our CD transport and various computer transports to show our readers there is an affordable way to get into USB based computer audio without breaking the bank.

The original V-DAC is no slouch. I have to say it definitely sounds better than the older MF DAC's such as the A3.24 from circa 2002. According to MF, it even outperforms any of the slightly older DAC's such as the X-DACv3 and even the Tri Vista 21 Tube DAC. Although I'd probably take a Tri Vista 21 over any of the other older MF DAC's based on its tubed output. If it were up to me, I'd go with V-DAC over the older designs based on its USB input and updated processing which the older designs lack. There's probably one exception: Let's say you have a tubed DAC that you love and want to add USB capabilities. That's where the V-LINK comes in but we'll save that discussion for another time. Right now, we're focused on the two MF DAC's, not their USB to SPDIF converter!

Let's touch on the main differences between the two DAC's before we go any further. After checking the Musical Fidelity website, we learned the basic differences. The finish/ overall look of the V-DAC has been upgraded to a nice silver case vs. the old plain black case. The USB input has received a kick in the pants by adding an Asynchronous USB input instead of the original Adaptive USB input. The older version was stuck at a 16/44 input ceiling for digital files where the newer version has been bumped up to accept 24/96 digital files. NICE! The older version had a distortion value of 0.005% where the new version has dropped down to 0.002%! Stereo separation has also increased on the new model to -105dB.

We have to say the biggest selling point to us was the inclusion of an Async USB input and the upgraded 24/96 native resolution. We were downsampling our digital files with the original V-DAC. Remember, even though our Hi-Res files were downsampled, we still unanimously agreed they sounded better than the Red Book 16/44 files played through the same DAC and digital player. We don't have to do that with the new version and we can actually upsample ALL our digital files to 24/96 if we like. We choose to send the files through to the DAC at their original sample rate. We don't like to upsample/ downsample our files if at all possible.



It's important to note that we went with the Pangea P-100 external power supply mated to the V-DAC II instead of the Pyramid PS-3KX external power supply we used with the original V-DAC. Any external power supply will better the included wall wart. The P-100 is the better unit if you're deciding between the Pyramid and the Pangea. Let's keep in mind both power supply units are of the switching variety and NOT linear power supplies. If you'd like one of those, we could make you one or you could purchase one from Teddy Pardo.


Well, let's talk about the sound of each unit. The original version sounds great with an external power supply. You don't have to spend a lot to upgrade the wall wart that's included. We spent about $25 on the Pyramid. As we stated before, the original V-DAC bests the older MF DAC's, even the Tri Vista 21 Tube DAC. (Though that's still up for debate) Now on to the new version, the V-DAC II. I have to say it definitely sounds better than the original. We are comparing both units with a CD transport as a source first. There is definitely a noticeable difference between the two. I feel an audiophile would be able to tell the difference right away. A non-audiophile may not be able to tell right away but I think he or she would eventually hear the value in the upgraded unit.

If you'd like us to describe what we're hearing, we would say the MkII puts out an overall better soundstage, deeper bass, better mids/ highs, and more detail. Again, it's hard to quantify but the difference is there although it is a slight difference. Obviously your mileage may vary depending on your system.

Now onto the USB input. This is where the MkII shines. We can now run our digital files in their native resolution, whether it's 16/44, 16/48, 24/88, or 24/96. We still have to downsample our 24/176 and 24/192 files to 24/96 within JRiver but how many albums are out in that format right now anyway? Not many! (See our JRiver Review which shows the user how to handle various file formats) We can now implement multiple bit-perfect playback modes since the MkII has an updated Asynchronous USB input. We are referring to the multiple bit-perfect output options within JRiver which are ASIO, WASAPI, WASAPI - Event Style, and Kernel Streaming. Each output mode should allow the user to fine tune the sound to his system and liking. Show me a CD transport that can do that! The above descriptions on sound and performance hold true for the USB input as well. The main difference is that the V-DAC II can now handle the various current bit-perfect playback modes. YES! 

It's great to step into the current USB technology playing field. The original V-DAC was a great little DAC but the V-DAC II has raised the performance bar even higher. Musical Fidelity really has a winner on their hands here. We've heard around the campfire that the MF M1-A DAC is the same as the V-DAC II but with a built-in power supply in one box. You can try the MF M1-A DAC if you really want to but I'd go for the above-mentioned set-up and save yourself $300! (OR, find a used EE Minimax DAC for ~$700). You don't get the AES/EBU digital input, XLR analog outputs, or the choke regulated power supply but do we really need those in this price range anyway? You can get a custom, non-switching power supply from Teddy Pardo for ~$350 which brings the V-DAC II up to/ surpassing the M1-A DAC's performance level for ~$50 less. Personally, I like when the power supply is away from the main processing components since this method keeps both sections isolated from one another. You make the call!

THANKS for reading and keep on listening!



Associated Equipment for this Review:

  • YFS HD-Ref-1 
  • McCormack SST-1 CD Transport
  • YFS Custom Direct "Passive" Preamp and Custom 6L6 Tube Power Amp
  • YFS/SCH K08T21 Custom Speakers
  • YFS Custom Interconnects, Cables, and USB Cables
  • YFS Custom Room Treatment


by Kevin OBrien on 01/23/2012

I have been using the modified Eastern Electric Minimax DAC Level 1 from Wayne at Bolder Cables for about 6 months. I can say it sounds great. So I know you're wondering how does it compare to the new Minimax DAC Plus? Let's just say it's worth your time to read more if you are considering either DAC.

First of all let me describe the stock Minimax DAC which is now discontinued but can be bought on the used market for around $700. It's a great DAC especially for the money. Unfortunately, the main constraint on the earlier version is its ability to only accept up to 24/96 digital files. However, this DAC sounds great and is a killer value.

Let's take the stock DAC one step further and send it to Wayne at Bolder Cables for the Level 1 modification. I was able to get a hold of one of these upgraded units and had the pleasure of using it for several months. Wayne recommends over 500 hours of break-in which I performed before critical listening. Let me tell you that the upgrade was worth the money at the time compared to the original unmodified version. This unit just plain smoked the older DAC's such as my Musical Fidelity Tri-Vista Tube DAC. There was no comparison. I believe this is due to the ESS Sabre DAC chips used in today's higher end DAC's which the Eastern Electric and Wyred4Sound DAC's employ.

Here comes the real meat and potatoes of the article, how does the DAC Plus stack up to the modified original DAC? Let's just say I noticed better resolution and the overall sound was more realistic to me than the original modded Level 1 DAC. Everything just seemed better to me. By how much I'm not sure I can quantify but I think it's safe to say most audiophiles would be able to hear the difference.

I like the fact that Alex lost the volume control as most folks use a preamp for attenuation and do not need it anyway. Wayne obviously bypasses the volume control on the original modded DAC so why incorporate it into the new version? Well, Alex chose to get rid of it which I believe helps let even more of the music through and keep the signal path even cleaner. I ended up using the same Psvane 12AU7 that Wayne sent with his modded Minimax DAC's and it worked quite well in my system with the DAC Plus. I was wondering if I was the only one hearing these differences or was this universal throughout the audiophile world?

I did not want to compare specs of both products and waste your time with the description of various inputs as you can do that by going to the manufacturer's websites (Eastern Electric and Bolder Cables) and see for yourself. Check out these sites if you are interested in comparing features, specs, etc. between the two DAC's. It's that simple. The one thing to note right away is the newer version of the Minimax DAC is slightly larger than the original due to separate power supplies for both the digital and analog sections unlike the original with only one power supply for both.


This DAC Plus stacks up VERY well to the Level 1 modded DAC and actually can stack up to the Level II mod from Wayne as well. I spoke with Bill O'Connell of Morningstar Audio and he agrees the DAC Plus is better than his fully modified Level II Minimax DAC from Wayne. It's that good. The one thing I do love about the new DAC Plus is its ability to accept 24/192 files from its USB input unlike the previous version. This is accomplished through the M2Tech USB interface within the DAC Plus. The DAC Plus uses VERY similar drivers to the M2Tech EVO which is to be expected as the same hardware is used inside the DAC Plus as I just stated. If you can get the M2Tech EVO working on your system, you will certainly be able to get the DAC Plus up and running in no time as well. One small caveat here in regard to drivers. If you are using a Mac you must uninstall any M2Tech USB drivers on your system before you proceed with the Minimax USB drivers. This is fairly straight forward. If you are using a PC, you will have to get rid of your M2Tech USB drivers by reinstalling Windows or contacting M2Tech for a script to do the job as well. As you can imagine, it's a little harder for PC users but this only applies if you already have M2Tech drivers installed on your computer audio source. Otherwise, get rid of any USB drivers from previous DAC's and devices BEFORE you install the Minimax USB drivers.

I love the fact that the user can switch between the tube output and the solid state output with a push of the button on the front panel. The solid state output does have slightly more detail but I prefer the smoothness of the tube output and will sacrifice a little detail for better overall sound. The phase button on the front panel will interest some folks as well although I did not find myself toggling back and forth between the two after playing with it for a couple minutes.

If you're wondering how the Minimax DAC Plus holds up against other DAC's I can give you a little insight. I am familiar with the Wyred 4 Sound DAC2 which I had in my system for several months. I switched from the DAC2 to the Level 1 Modded Minimax and I noticed it sounded more realistic and a bit smoother than the DAC2. The DAC2 just seemed a little too dry and it lacked the liveliness of the Minimax Level 1 DAC. I like the Minimax DAC PLUS slightly better than the Level 1 Minimax so this should give you and idea on how all 3 DAC's stack up. The W4S DAC2 was able to accept a 24/192 digital signal via it's digital coaxial input UNLIKE both Minimax DAC's which were stuck at 24/96! Don't believe every spec sheet you come across. In this instance I assumed it worked until I gave it a try. I have to be honest, this still bothers me a little. Which means, my quest for my final DAC has not yet ended. (Just trying to help potential buyers here - I am not affiliated with ANY audio manufacturers!)

With the new features added to the already great Minimax DAC why torture yourself wondering if the few extra hundred bucks is worth it or not for the MKII version? For $1100 you cannot go wrong here and as far as I'm concerned. Don't walk but RUN to the Eastern Electric website and get yourself one of these before you lose your mind. Stop thinking about it and just do it! It's that good. The one question you may still ask yourself is, will Wayne modify the DAC Plus as well and take it to the next level?

Stay tuned for more details!

UPDATED 2/23/2012:

Apparently Bill from Morningstar Audio does not want Wayne of Bolder Cables to modify the New Minimax DAC PLUS so there will be no Level 1 Modification to the DAC PLUS or any modification from Wayne for that matter. There is however a Level 3 Modification for the Minimax MkI DAC. Check Wayne's forum outlet,  Audiocircle for more details. I'm a little disappointed to say the least...



 Associated equipment for this review:

  • Von Schweikert VR5-HSE (Hovland Special Edition) Speakers
  • Quicksilver tubed Preamp and Monoblocks
  • IBM Laptop for source with Foobar 2K Digital Audio Player
  • Theta Digital Carmen II CD Transport
  • EE Minimax Phono Stage
  • VPI Scoutmaster Turntable with VPI Zephyr Cartridge
  • Equitech/ PS Audio Balanced Power Conditioners
  • YFS Custom Cables and Interconnects
  • YFS Custom Room Treatment
  • Herbies Audio Lab Dampening Devices and Tube Dampers



Enter RAAL, a ribbon driver manufacturer based out of Serbia headed up by Alex Radisavljević. Alex has been submersed in audio since 1993 but has been designing and building ribbon drivers for transducers since 2007. These ribbon drivers are used by a plethora of HiFi speaker manufacturers including Salk, Nola, Ascend Acoustics, and Vapor Audio just to name a few. RAAL makes a killer ribbon driver and that's hard to argue at this point. Facts are facts.

Now enter Danny McKinney, president of Requisite Audio, based in Los Angeles. Requisite Audio fills the needs of the very demanding pro audio segment which deals with specialized gear for recording environments such as custom microphones and nearfield monitors. Danny is a very likable guy and never shies away from a great conversation about anything audio related. I first spoke to Danny just a few weeks prior to writing this article and we shared some interesting stories about headphones and our experiences in the Industry. I don't think I've had a better 'first impression' after speaking to someone for only half an hour.

Now, fast forward to the present. I have been looking for the next best thing as far as headphones are concerned after ending my relationship with Focal about 8 months prior. I had run into issues in relation to their Utopia headphones. My customers were, in some extreme cases, downright angry and felt betrayed by the way Focal was dealing with their unfortunate quality control problems. Focal made it right for all of my customers eventually, but not without some serious hoops to jump through to get there. That's not how you do business in a such a close knit community such as HiFi. To make a long story short, we both parted ways. I don't want to represent products that I can't stand behind with complete confidence.

How would I fill the void after losing a line like Focal? Well, find a headphone that performs on an even higher level than what was previously thought possible. Here's where Alex and Danny enter into the picture. Alex and Danny decided to partner up to form what is now known as RAAL-Requisite. The $3500 RAAL-Requisite SR1a is the product Danny and Alex came up with as a joint venture and it's definitely making a very big splash in the headphone world. In fact, the SR1a has set the bar for all other headphones in terms of performance to price ratio. Some would argue that the SR1a is THE top headphone to beat and can hang with the likes of the Sennheiser HE-1 (and may actually surpass it). That's a very bold statement!

So, how did I stumble upon the SR1a? One of my customers turned me on to them as a replacement for his recently sold Utopia. And boy, I'm so glad he did. Thank you Scott! After hearing his impressions on the SR1a, I knew I had to have them and see what they could do in my system. Scott emailed Danny and copied me on a message introducing both of us to one another. This is how I ended up meeting Danny.

Danny, being the nice guy that he is, brought YFS on as an authorized dealer after a simple conversation. That's how Danny works. No contracts to sign, no red tape, just a conversation and a 'virtual handshake' over the phone. That's how business should be done. After giving Danny my credit card information, he had a pair sent out to me immediately. Upon receiving the SR1a, I hooked them up to my system in my office and began to burn them in. My initial impression was 'Wow! These are super detailed yet not harsh or bright at all. These are dead neutral!" How is this possible? Ribbons are known for being a touch on the bright side in the 2 channel arena and must be matched properly with the appropriate gear to make sure they are not fatiguing. Well, not all ribbons work this way but the ones I have experience with do. Not so here.

50 hours later and the SR1a were even more neutral and just gave me a super clear picture of what I fed them. Play a bad recording and you hear the shortcomings of your music. But play a great recording and you get the best experience of that recorded event you can imagine. I really appreciate gear like this that is brutally revealing and honest. After all, these headphones were designed with the recording studio environment in mind where a mastering engineer would be using these to tweak and place the finishing touches on his or her creation. Fast forward to 250 hours and any hint of brightness or forwardness was now gone. The bass response was also stronger and more notable after break-in. So much for my previous experience with ribbons. I'm getting a completely different presentation than what I initially thought I would get with the SR1a which is quite impressive.

If the SR1a is a little on the bright side after break-in and you want to knock down the treble energy while enhancing the midrange and bass response, our custom hand-wound YFS 'Super 30' pure copper Litz cable will work perfectly and provide good synergy. Our YFS 'Super 30' Litz cable, when crafted specifically for the SR1a, contains double the standard conductor material to keep the cable impedance low and the current delivery as plentiful as possible. Just let us know if a custom YFS SR1a copper Litz cable is necessary and we'll twist one up for you without hesitation. Pricing depends upon the length of the cable. Feel free to contact us for lead times and to obtain a price quote for the specific cable length you have in mind.

How does one listen to a proper ribbon-based headphone anyway? Think of hanging a pair of tiny speakers in front of your ears. That's exactly what the SR1a is, a pair of ribbon drivers encased in a carbon fiber enclosure set in front of your ears. It's hard to imagine but this means you don't have traditional ear cups nor do you have traditional headphone sound. The sound coming out of the SR1a does not feel like it's coming out of a driver adjacent to your ears. It truly reminds me of a great pair of speakers situated extremely close to your head, like an extreme version of a studio nearfield monitor setup. I believe this is why Danny coined the term, 'Earfield Monitor' for the SR1a as that's the most accurate description I could come up with if you asked me to describe them. This unique design equates to the sound staging not being constricted at all. The SR1a feels like an 'out of head' experience. 

How does one drive a headphone like the SR1a, which presents a 0.2 Ohm load, with even the most powerful amplifiers available? RAAL-Requisite provides an 'interface box' that sits between the headphone and the amp. This small black box has a male 4-pin XLR connector on the front faceplate and a standard set of twistable locking binding posts (just like you would find on the rear of a 2 channel stereo amplifier) on the rear faceplate. Banana plugs or spades will work with the interface box. This black box allows the user to mate their favorite speaker cables to their favorite amplifier without fear of damaging any of their components in the process. RAAL-Requisite also employs a female 4-pin XLR connector on the amp-side of the factory headphone cable which means there's no way to plug the SR1a into a standard headphone amp. Most standard balanced headphone cables use a male 4-pin XLR connector instead of a female one. You have to admit, that's pretty darn smart.

Okay, so now that we know how the SR1a sounds, how does it feel sitting on top of your head? The SR1a rests on your head via two genuine leather straps held together with a metal headband. The main larger leather strap sits on top of your head like a traditional 'suspension style headband' but the smaller leather strap goes behind your head to keep the SR1a from sliding forward. I noticed during my listening sessions that the small strap could be placed on top of the large leather strap to make the SR1a sit on the top of your head like a traditional headphone. I have not decided whether I like them better with the small strap engaged behind my head or sitting on top of the larger leather strap. The jury is still out on which resting position I prefer. 

The SR1a is a very comfortable and particularly lightweight design. Since the drivers do not encompass your ears via ear cup pads like a standard headphone, I never found myself wanting to take them off. Without ear cups, your ears and head will not get sweaty during long listening sessions. This is a major bonus. Small lined pieces of foam are attached along the front / top of the driver enclosures which allow the ribbons to 'lay' next to your ears. These pads make contact with the sides of your head while listening. I did not find the pads overly annoying at all. Overall, the SR1a may need to be refined as far as fit and finish goes, but I personally think these cans are a home run right out of the gate.

Another very handy feature of the SR1a is the ability to adjust the toe-in of the drivers in relation to your ears and head. The drivers are mounted to the headband via a rotating swivel point which provides enough resistance to stay in place when rotated to the exact position you desire. After playing with the angle of the drivers for several hours, I ended up keeping them almost as flat as possible with only a slight amount of angling outwards from my ears. I am thinking this specific orientation may be tricking my brain into thinking the SR1a is an actual headphone more so than the other positions I tried. More time will be needed to settle on a final driver angle position but for now, I'm very happy with what I'm hearing.

How will the SR1a hold up over time? The ribbon drivers are rated to last several thousands of hours but will need to be replaced once this finite period of time is reached. Not to fear, on the RAAL-Requisite website you will find replacement drivers for $350 a pair. If you should happen to need your drivers replaced in an extraordinarily small amount of time (abnormally low hours of operation), that instance is covered under the 5 year warranty. If you are in doubt about specific timeframes for driver life or have any specific questions about warranty, it's always best to contact RAAL-Requisite directly. The replacement ribbon cartridges can be replaced easily by the end user by simply removing the old drivers and sliding the new ones in their place. This takes all of 30 seconds which also means there's no need to send in the SR1a for warranty / repair as this can be done at home after parts arrive from the manufacturer. This isn't exclusive of the drivers either. Replacement pads, interface boxes, the Pelican travel case, and a factory replacement cables in various lengths (spanning from 7 feet to 14 feet) are available from the SR1a accessories link on the company website. These finer points show that the SR1a is a special product. It appears Alex and Danny have thought of almost everything.

Let's talk about what you'll need to get the most out of the SR1a should you decide to give them a shot. Danny recommends a stereo amplifier with at least 150 Watts of power into a 4 Ohm load. This means any solid state integrated amp or preamp/ amplifier combo should work just fine as long as it adheres to the above specifications. Tubes are more than welcome as well. The guidelines for tube amplification are a little less stringent as tube amplifiers do not clip the same way when they are stressed like a solid state amp does. This means a 75 Watt to 100 Watt tube amp or integrated amp should do well for amplification duties. The interesting thing about the SR1a that surprised me the most is that super high-dollar amplifiers and preamps are not needed to get an amazing listening experience. That translates to not having to spend thousands of dollars on electronics to mate your source to these babies. In fact, your source / DAC is more important when it comes to selecting gear for the SR1a than the amplification which should really help listeners if they are on the fence about whether or not the SR1a is for them.

Another interesting thing to note here, which is also a sign of great gear in my opinion, is that the SR1a are VERY receptive to changes in gear and cables. Switch out your speaker cables and interconnects and you will notice a change immediately. This means the SR1a is a great tool for cable and equipment designers. The SR1a allows us to 'voice' our products and tweak them until they sound the way we want them to without straining to hear differences.

If there was anything to complain about regarding the SR1a, it would be the overall look of the headphone. There's no way around it, the SR1a look like something out of a Star Trek episode! But, this is hardly concerning once you hear what they can do. So, in a nutshell, there's really nothing to complain about at all. RAAL-Requisite has a winner on their hands and the rest of the competition has a lot of work to do to catch up, if they can...

Until next time...

- YFS Review Team


by Kevin OBrien on January 15, 2022


Cans are key to feeding the 'audiophile addiction' when external peripheral conditions do not lend themselves to standard listening. Headphones are a critical tool when there are others in close proximity to your speaker system or you feel the need to 'dissect' a new album or piece of new test gear. If listening sessions should fall within extremely early or late times of the day, having a trusty set of reference cans is a life-saver. Speaking of cans, it's been way too long since we've had the opportunity to test-drive the latest, updated Audeze flagship offering. Well then, here we go.

After the 3-year hiatus from our YFS LCD-4Z review, we were ready to dive back into whatever the headphone gurus in Santa Ana were prepared to throw at us. Okay, so we know what we're getting ourselves into here. We made a few assumptions going in since these were yet another planar flagship from our friends at Audeze in Southern California. We bet these have the signature 'house Audeze sound' but are more refined than their previous flagship, the LCD-4. Sure, these are just the same old Audeze cans in a newer, smaller, lighter shell... Right?

Wrong! None of that could be further from the truth as it turns out. Meet the latest planar flagship from Audeze, the LCD-5. The LCD-5 is quick, accurate, detailed, lightweight, and difficult to drive. Planars aren't the easiest load to drive but these were something all-together different than what we were used to seeing from Audeze (more on this later). The laid back sound signature with an emphasis on the bass and midrange was gone. In its place was what sounded more like hints of a possible reference model of old from Sennheiser but with better bass and overall resolution. Think high frequency energy here and not laid back necessarily. 

Speaking of changes, let us briefly touch on the physical differences between the LCD-4 and LCD-5. This newer 5 has much smaller earcups and a totally redesigned headband / suspension system. The suspension system of old, including the yolk and gimbal from the classic LCD-2-type designs, has been replaced with a completely new design. (The jury here at YFS is still out on this particular change) The latest, updated drivers are 90mm in diameter versus the 106mm diameter of the older 4. The most significant change has to be the weight of the cans themselves. These are LIGHTWEIGHT! I mean, really light. 420 grams to be exact. LCD-4 weighed in at almost 700 grams! One of the drawbacks of the older original Audeze models was the extreme weight of the setup. For instance, long listening sessions were impossible for us with the LCD-2. 


It seems everything has changed in regards to the new LCD-5 design and layout when compared to the older sibling. Old Audeze habits have certainly died this time around. The 5 is light enough to wear for multiple hours at a time. Listening sessions will last through the night and into the wee hours if source material will permit. In fact, when we first mated the 5 to our YFS demo Ferrum Audio stack, we planned on listening to just the title track on Talking Heads' Speaking In Tongues 24.96. We ended up listening to the entire digital LP! After a small taste, we just couldn't help ourselves. This was a very welcomed first impression.

One area that called attention to itself was the difficult load the LCD-5 presented us with. Audeze is not known for their easy loads to drive, but this was new for us. We had no difficulty driving the LCD-4 or any of the other over-ear Audeze cans for that matter (electrostats excluded obviously). The LCD-5 just didn't want to cooperate with the gear we had in-house. This is what spurred us to reach out to Ferrum Audio to get an amp into our showroom to help with our LCD-5 evaluation. Our ECP Torpedo III amplifier did work but we were missing that all important PRaT and midrange magic. This amp was simply not powerful enough to make the LCD-5 sing. Something was missing for sure. Our McIntosh MC202 sounds incredible mated with most of our reference cans but the LCD-5 and MC202 did not work together, at all. A loud hissing sound came from the earphones and we knew immediately there was a serious problem with this pairing. We have a feeling the 90 dB efficiency of the LCD-5 combined with the low output impedance of 14 Ohms just wasn't playing nicely with our YFS test system.


Switch over to the Ferrum Audio OOR + HYPSOS stack and our pure copper Litz YFS 'Super 30' cable and everything changed. The bass response was more detailed than anything we've heard from a headphone, albeit a bit on the light side. Huh? It's okay. We're used to it. Every headphone we listen to needs the lower bass regions bumped up a few dB to get things sounding right to us. There was no exception here with the LCD-5. After bumping up the lower bass a bit, we were rewarded with an amazingly detailed and resolute sound, yet with a completely full and dynamic presentation. "These are neutral reference cans worthy of testing gear with!", is the first thing that popped into our heads. WOW! This must be the furthest result from what we were initially expecting. Welcome to the 'New Audeze' folks. This is entirely new territory for Audeze and frankly, we are excited.

Not to worry, if you still lust for that Audeze sound of the past, as there are ways to smooth out the LCD-5 and 'darken' them up. Unfortunately, it appears it will have to be in the form of cabling and / or equipment. We don't really see any other way around it. There could be a pad tweak potentially down the road but that may weaken the bass response and effect the overall detail in the bass regions (that we enjoy so much)? Not sure? That's up to someone else as we are too busy these days to take something on like that. Regardless, this new Audeze flavor may take some 'getting used to' but proper component synergy is paramount with the LCD-5 and plays an important role in getting the best experience out of this new flagship.

Fit, form, and function are all top-notch with these new reference earphones from Sankar and the Orange County crew. Expect some of the best comfort, presentation, and sound quality available in a headphone here. Are they worth the $4,500 price tag? That's up for you to decide. If you can tame the LCD-5 with proper amplification, a great source, and a smooth aftermarket cable, you will be one happy camper.  This much we can promise you. 

As always, feel free to reach out to us with questions or concerns. We are  authorized  Audeze dealers. We can get you into a pair of LCD-5 for less than you think.

Thanks for reading and spending your time with us.



by Kevin OBrien on January, 22 2019


Do reference-level headphones belong at home? This is the question we keep asking ourselves, especially as of late. It seems the portable headphone market is larger than we first thought. A quick search online yielded a plethora of portable DAC / amp combo units available for taking your audiophile habit on the go. It never occurred to me until now that this could or should be a good idea for some odd reason. I have never experienced my HiFi anywhere but at home with my reference gear.

It seems this portable HiFi movement has spurred Audeze to introduce a new addition to their lineup, the LCD-4Z, that allows HiFi enthusiasts to take a reference quality headphone anywhere. The LCD-4Z offers up a very similar headphone to their flagship, the LCD-4, except it's designed around being as easy to drive as possible. The drivers in the 4Z have been changed from a 200 Ohm driver with a sensitivity of 97 dB to an all new 15 Ohm driver with a sensitivity of 98 dB. The wood rings and metal grille on the original LCD-4 have been replaced with a lightweight single-piece magnesium cover. Not only does this create an ultralight LCD series headphone, this adds a new twist on an already great headphone. I am on vacation as I type this and the LCD-4Z came along with me. Point taken. You can take your reference HiFi gear with you anywhere.

The one very important thing to remember is that these 4Z drivers are designed for portable sources and NOT standard stay-at-home headphone amps (or stereo speaker amps for that matter). If the LCD-4Z is paired with your standard headphone amp, you may be underwhelmed with the results. I know that's what I experienced. When the 4Z landed at my doorstep, I burned them in for 300 hours. After burn-in, I then began pairing them with multiple sources and amplifiers like I normally do. I went from amp to amp and regardless of which amp was in the chain, I kept getting results that just didn't sound right. The presentation just sounded 'off'. Then I reached for my phone and plugged the 4Z in just for fun. All of a sudden, the music started sounding better, much better. Then it dawned on me, duh, the LCD-4Z is designed for low-power sources. If you want Audeze's reference sound with standard higher powered amplifiers, the LCD-4 is your solution and the proper fit.

If over-ear, open-back portability is what you're after and you want to take Audeze's reference over-ear sound with you, these are the perfect cans for the job. The fit and comfort level of the 4Z is unparalleled when compared to the rest of the LCD lineup (excluding the LCD-MX4 which is identical to the LCD-4Z fit-wise). This was impressive as other models in the LCD lineup almost feel like wearing a helmet sometimes. This was not the case with the 4Z. This headphone seemed to be bucking the old Audeze way of doing things which I really like.

So, now that using my standard gear was out of the question, how was I going to review these cans? It was time to get in more review gear to review my other review gear. I wanted to make sure I was using a proper portable source when reviewing the 4Z. This much I knew. This lead me to mate the 4Z to the Woo Audio WA8 Eclipse portable DAC / Class A tube amplifier. The Woo Audio unit (MSRP of $1800) seemed to be priced below some of the other reference portable gear from other manufacturers but well above some of the 'affordable' portable gear I was trying to avoid. The WA8 Eclipse appeared to be a great pairing for the LCD-4Z on paper and proved to be just that in the flesh. Hook up a laptop to the WA8 Eclipse with a USB cable and you're off to the races, it's that easy. The WA8 Eclipse warmed up for half an hour and then I hit play and the 4Z began to sing. After about 5 seconds of each track, I got lost in the music. My first listen to this duo lasted 3 hours but it only felt like 30 minutes. The WA8 Eclipse / LCD-4Z combination was so smooth and addicting. I could live with this pairing for travel and at work and be happy forever, it was that good. 

With a headphone of this pedigree, it seemed a waste to only use them at work or on the go. I found another way to enjoy the LCD-4Z at home in my reference 2 channel system. I ended up coming up with an adapter to take the left and right signal out of my preamp and send it to my balanced 4-pin headphone cable. This gave me a low powered source component to mate with the LCD-4Z but allowed me to use my reference YFS music server and EMM Labs DAC as the source. This particular equipment pairing produced the most amazing sounding Audeze headphone I have heard to date! I'm hearing a presentation from these headphones that reminds me of a great 2 channel stereo system.

After the initial amazement wore off, I started trying to account for what I was hearing. The only explanation I could come up with was the following: I am taking an entire component out of my chain when listening to the LCD-4Z. When I use the standard LCD-4, I am hooking up to the headphone amplifier AFTER my stereo preamp, DAC, and music server. Therefore, listening sans amplifier I am getting even closer to the original source information. 

The Audeze LCD-4Z gives me the most versatile headphone for work, travel, and home use depending upon the gear I pair it with. I can't think of any other headphone that can do that and still quench my thirst for reference quality listening. If you like the over-ear open-back Audeze 'house sound', this latest offering will not disappoint (IF it's paired to the proper gear). We tip our hats to the engineers at Audeze for coming up with a very special product.



A big thank you goes out to Evan Grimm, the Head of Product Training and Tony Hamilton, the National Sales Manager at Audeze for making this review possible. Thanks guys! In fact, these headphones are so unique and they impressed me so much, I called Tony and gave him my credit card. I wasn't going to be sending these hand crafted beauties back to California after all. Yup, they are that good...

I would personally like to thank all of you for reading and visiting the site. If you have any questions, feel free to reach out to us and we will do our best to respond in a timely manner.

Until next time...

 - YFS Review Team



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