Preamps - Analysis and Reviews

[Johnseye]

I think I can speak for the majority of this community when I say we're all in a constant search for improving our two channel sound.  About a year and a half ago I began an endeavor to focus on rebuilding a two channel system.  I've made many changes since then.  This most recent being the addition of a preamp.  I have a Marantz prepro that I use for multi-channel and my Audio Alchemy DAC has a pre.  Both do a good job.  I was very happy with how the AA sounded, but I had read quite a bit about using a tube pre and I wanted to see what that was all about.  So I began a several month effort to audition a handful of respectable tube pre's and tried to stay around the $5k range.  During this time I learned about Benchmark's release of their DAC3 and because I've found their AHB2 amp to be the quietest amp I've ever heard, after talking to Rory at Benchmark I threw that in the mix as it has a pre.  Then a local dealer told me about the upcoming Anthem STR Pre, another solid state.  He had a new Anthem integrated with a similar design concept so I gave that a listen as well.  There are macro changes we can make to our system and there are micro changes.  After the choice of speakers or headphones, the preamp can make this biggest difference.  That said, I find it interesting that there is no section in this forum for the likes of preamps or amps, which is why this review landed in the General section.  If others would like to contribute to this thread by adding their own preamp review, including any I've discussed, I'm good with that.

 

Testing was done in both analog and digital realms.  I'd be happy to share the various cables I swapped out, turntable and music sources if requested but otherwise won't get into that in this first post.

 

The contenders:

 

Rogue Audio RP-5 - $3.5k

Backert Labs Rhumba 1.2 - $3.4k

Backert Labs Rhumba Extreme - $5.5k

Benchmark DAC3 HGC - $2.2k

Anthem STR Integrated - $4.5k

Audio Research LS28 - $7.5k

Atma-Sphere MP-3 - $5k

Atma-Sphere MP-3 with phono stage and Vcaps - $7k

 

 

Rogue RP-5

http://www.rogueaudio.com/Products_RP5.htm

This was the first tube pre I took home.  It's been a while so my recollection won't be as detailed as the other pre's.  I plugged it in, let it warm up and man was I disappointed.  I had heard so much hype about tube pre's and while I've heard them at Axpona and in stores, that was with completely different equipment.  There is one caveat to this experience.  The RP-5 doesn't have balanced outs so I had to use my older Emotiva amp as the Benchmark only has balanced in.  Noise level from the Emotiva aside, the RP-5 sounded flat.  The dimensionality shrunk by comparison to the AA pre.

Backert Labs Rhumba 1.2

http://backertlabs.com/to-purchase/

The Rhumba sounded much better by comparison to the Rogue.  There was more dimensionality as well as very good top and bottom end clarity and oomph.  It was more in line with what I was looking for, but it still sounded a bit like solid state.  I also had the Benchmark DAC3 and ARC LS28 at the same time so was able to compare all back to back.  The Rhumba's remote is a simple volume control, that's all.  Andy, Backert's president was very communicative.  When I gave him my initial feedback he sent me out another set of tubes to try.  When you get to my comments on the ARC you'll understand why.

 

 

Backert Labs Rhumba Extreme

Very similar to the 1.2.  If I were to describe the difference it would be that the Extreme is slightly cleaner sounding.  The $2k is probably better spent elsewhere.

 

Benchmark DAC3 HGC

https://benchmarkmedia.com/collections/digital-to-analog-audio-converter/products/benchmark-dac3-hgc-digital-to-analog-audio-converter

The Benchmark sounded extremely clean.  It paired up nicely with the AHB2 from that perspective.  The remote is solid and everything is very well built.  It was however very similar to my AA DAC in almost every respect.  The only real difference was in the clarity which contributed to a bit more dimensionality.  But it was clinical to my ears and not in the direction I wanted to go.  My entire two channel system up to that point was built around clean and clear.  Now I needed to add some body and musicality, not more crispness.  If I were to choose between the AA and the DAC3 I'd probably take the DAC3, but the improvement was so slight it didn't justify keeping it.

 

Anthem STR Integrated

https://www.anthemav.com/products-current/model=str-integrated-amplifier/page=overview

I won't go into this one too much as I didn't give it that long of an audition.  It's a decent sounding solid state amp.  Where it shines is in its room correction which I didn't setup.  It also allows for a more seamless subwoofer integration.  If I were looking for a new solid state pre I would strongly consider the upcoming STR for these features.  From a sound quality perspective without the room correction it sounded flat and 2 dimensional.  The reason why I didn't use the room correction is because it was setup for the store and they didn't give me the mic.  Not a good way to audition a pre.

 

Audio Research LS28

http://www.audioresearch.com/en-us/products/preamplifiers/ls28

I had been sharing my plans and experience with @Ralf11 in another thread and he recommended I give ARC a listen.  While I had heard some things about ARC I hadn't given them serious consideration.  Many of the commentaries in reviews I read people had tried ARC, then moved on to something else.  Audio Research has been around for a while.  I found a local dealer and the owner agreed to let me take an LS28 home.  His store was about an hour and a half away but he lived about 45 minutes from me so we met close to his home.    I hadn't even asked about the price yet.  When he told me what it was I was thinking, well this is about double what I want to spend.  I thought I'd give it a listen but couldn't imagine taking it much further.  When I got it home and started to listen I thought wow.  Just wow.  This is what people were talking about when they hear something good from a tube pre.  The soundstage the LS28 creates is big.  Not overwhelmingly big,  but it made other pre's I'd listened to small by comparison.  It was like when I heard Magnepan for the first time.  A large, full soundstage.  Then there was the fullness and balance of the sound.  A full midrange combined with excellent highs and lows to probably the best combined tonality I'd ever heard.  This is what may lead to the next thing I noticed and that was the timing.  That blew me away.  I was hearing the timing between musicians where their changes were clear as day.  This I had never heard in a system.  Mick, the owner of the store who lent me the LS28 said he thought it was incredibly close in sound to their Ref 6 and that this was a new step up for Audio Research.  I then went out and read whatever reviews I could find on the LS28 and others were confirming a lot of what I heard.  It's an incredibly light unit by comparison to the other pre's.  I think the chassis must be made out of a lightweight aluminum.  The remote is hefty and solid however.  Unlike the Backert remote it can do everything the interface can.  I could go on about this pre and likely will later, but this was my new standard.

Atma-Sphere MP-3

http://www.atma-sphere.com/Products/#MP-3

Ralph, the owner of Atma-Sphere spent a couple hours over multiple calls chatting with me about technical details.  He's an incredibly patient and knowledgeable engineer.  Unfortunately when I receive the MP-3 it was out of phase.  I couldn't get a center image, so he recommended I swap polarity on a single speaker.  That did it.  There were a couple other issues I clarified with him and he eventually sent me out a replacement which I just got today.  This time I opted for full Vcaps as well as a phono stage on his recommendation.  I've had the other MP-3 for a few weeks now so plenty of time to compare it to the LS28, which I still have thanks to Mick's graciousness.  The MP-3 is the closest thing I've heard to the LS28 and by some characteristics it's better.  It carries the same soundstage which I found very interesting.  The coincidence is that ARC, Atma-Sphere and Magnepan are all based in the Minneapolis-St. Paul area, and they all have amazingly similar soundstages.  What the MP-3 does better, and only very slightly, is in its clarity.  Instruments are a little more defined, maybe a little brighter.  However the MP-3 doesn't have the same feeling of timing that the LS28 has.  Perhaps there's a slight lacking in the midrange, I'm not sure.  The replacement MP-3 I received also has a remote where the first one didn't.  The remote is the exact same one as the Backert, just volume.  There is an actual belt motor that turns the volume knob inside of the MP-3.  This is by design to keep with their minimalist approach to the circuit board.  Unfortunately I've run into some issue with this version of the MP-3.  The volume control has steps for each level and the remote doesn't seem to match with those steps.  I will also hear a significant amount of white noise when the volume is in between steps and the remote volume lands right on those spots sometimes.  Another issue I've found is that this version has a significant amount of noise when idle.  It's possibly due to the phono stage as when that's active there's much more hiss.  But the linestage also has more noise than the other MP-3.  I'm not sure what the issue is, but it's a shame because this is a really nice sounding pre otherwise.  It's also fully balanced and has a patent on that engineering.  Take a look at the website for full details.

 

 

And the winner is the Audio Research LS28.  Thanks Ralf.  Mick has extended his offer and allowed me to keep his store's model until mine is built and arrives.  He'll stop by when it's ready to sit down for a listen in my theater room where this is all setup.  I've asked him for some advice on any additional room treatments and equipment positioning.  I've built all my current room treatments with acoustic cloth and duct dampening insulation.  I've had a pro come by and calibrate my theater equipment, but never from a 2 channel perspective.  Mick was trained by some well known room acoustic engineer in Germany who's name I've forgotten so I'm looking forward to his opinion.

 

During the past few months I've also played around with moving the pre away from the amp and speakers using a balanced run.  For some reason when I did this I thought the sound closed up a bit.  I went from 1m XLR to 4.8m between the pre and amp, but this allowed to shorten the length of my current phonostage to pre single ended interconnect.  It could be that the new XLR cable is from DH Labs where the previous is Audioquest.  Ralph at Atma-Sphere included a 5m XLR pair of Mogami cables with Neutrik connectors, and that sounded closer to the Audioquest cables.  This is another area where more testing is needed.

[Ralf11]

Thanks John.  

 

What was in front of the pre-amps?  i.e. digital or analog, or both?

 

BTW, I think Audio Research may put dampening material on the cases in strategic areas.

 

I also noticed an improved "sense of pace" in the music when going from a Sonic Frontiers Line One (with old tubes) to the LS25 Mk II.  I'd always thought it was BS when the term was used by Stereophile's reviewers, yet there it was.  How it does that I dunno, but it is a descriptive term for whatever is going on.

[Urs]

I completely agree with you, John.

My own experience a few month ago: I had the opportunity to test an ARC Ref 6 preamp at home. Replacing an Ayre KX-5 (not twenty) by the ARC Ref 6 made a huge difference. The difference was in the class/magnitude of different speakers. I did not want to put so much money into a preamp... but I had to, I just couldn't resist after hearing the ARC in my system.

I think the influence of a preamp is way underestimated. E.g. I never experienced these kind of differences between DACs.

[rando]

Atma-Sphere was a new one on me so I googled them and clicked on their provided photos.  When this loaded I half expected a glass shield to lower and my screen to start shaking.  MP-3 is their newest product in all conceivable fashions.

 

[mourip]

I would add the Linear Tube Audio MicroZotl 2.0 with LPS to your list. The circuit is designed by David Berning, licensed by LTA, and made in the US. It has a headphone out, Remote Control option, and three inputs. It uses readily available tubes: 6SN7/12SN7 and 12AT7. The sound is very clear, tonally correct, and dynamic with tube richness without the old school euphonic tube sound. The external LPS is excellent and puts out 12V so one could also experiment with another LPS. NOS tubes bring it to another level altogether. The 12SN7 tubes are cheap and real "sleepers".

 

 

[Johnseye]

11 hours ago, Ralf11 said:

Thanks John.  

 

What was in front of the pre-amps?  i.e. digital or analog, or both?

 

BTW, I think Audio Research may put dampening material on the cases in strategic areas.

 

I also noticed an improved "sense of pace" in the music when going from a Sonic Frontiers Line One (with old tubes) to the LS25 Mk II.  I'd always thought it was BS when the term was used by Stereophile's reviewers, yet there it was.  How it does that I dunno, but it is a descriptive term for whatever is going on.

 

Sources feeding the preamps were an Audio Alchemy DDP-1 DAC and a VPI Prime with Ortofon Quintet Black cart to a Simaudio 110 phono stage.  The AA DAC was fed either direct from my server via USB or with an sMS-200.  DAC to preamp connections were always balanced.  Simaudio phono stage to pre was single ended except for what I tested yesterday.  I purchased a balanced out from the VPI Prime and that went direct to the Atma-Sphere MP-3 because the MP-3 was the only pre I tested with a phono stage, not to mention a balanced in phono stage.

 

Yes, I suppose sense of pace is part of the timing, but it was more than just the pace of the music.  As odd as this sounds I felt more engaged with the music to where I could hear the timing communication between musicians.  This is more easily heard with jazz as there are clear handoffs between instrument solos.

 

7 hours ago, Urs said:

I completely agree with you, John.

My own experience a few month ago: I had the opportunity to test an ARC Ref 6 preamp at home. Replacing an Ayre KX-5 (not twenty) by the ARC Ref 6 made a huge difference. The difference was in the class/magnitude of different speakers. I did not want to put so much money into a preamp... but I had to, I just couldn't resist after hearing the ARC in my system.

I think the influence of a preamp is way underestimated. E.g. I never experienced these kind of differences between DACs.

 

I think the DAC is the next most impactful component after the speakers, then the pre.  The amp probably falls after the DAC.  The pre is way underestimated and finding the right one for your sound preferences is like picking out a pair of speakers.

 

3 hours ago, rando said:

Atma-Sphere was a new one on me so I googled them and clicked on their provided photos.  When this loaded I half expected a glass shield to lower and my screen to start shaking.  MP-3 is their newest product in all conceivable fashions.

 

 

The MP-3 is their preamp and I should note that what I auditioned is the MP-3 Mk 3.3, their latest version.  They make tube amps and a headphone pre as well.  I can't stress enough how amazing the MP-3 sounds.  Had I not experienced the issues it would have been the best choice.

 

3 hours ago, mourip said:

I would add the Linear Tube Audio MicroZotl 2.0 with LPS to your list. The circuit is designed by David Berning, licensed by LTA, and made in the US. It has a headphone out, Remote Control option, and three inputs. It uses readily available tubes: 6SN7/12SN7 and 12AT7. The sound is very clear, tonally correct, and dynamic with tube richness without the old school euphonic tube sound. The external LPS is excellent and puts out 12V so one could also experiment with another LPS. NOS tubes bring it to another level altogether. The 12SN7 tubes are cheap and real "sleepers".

 

 

 

Thanks @mourip I hadn't heard of this pre before.  Hopefully I'll be able to give it a listen in the future.  I certainly like the LPS option.

[Speed Racer]

Here is a preamp!:

 

http://www.dsachsconsulting.com/custom line stage.html

[Speed Racer]

3 hours ago, mourip said:

I would add the Linear Tube Audio MicroZotl 2.0 with LPS to your list. The circuit is designed by David Berning, licensed by LTA, and made in the US. It has a headphone out, Remote Control option, and three inputs. It uses readily available tubes: 6SN7/12SN7 and 12AT7. The sound is very clear, tonally correct, and dynamic with tube richness without the old school euphonic tube sound. The external LPS is excellent and puts out 12V so one could also experiment with another LPS. NOS tubes bring it to another level altogether. The 12SN7 tubes are cheap and real "sleepers".

 

 

 

http://www.superbestaudiofriends.org/index.php?threads/microzotl-2-0-review.1750/

[rando]

The MP3.3 gave no clue whatsoever to the personality of their other products.  Assuredly, consumers trained to expect a certain look, a sleek metal box, eventually saw him relent to the detriment of his expressive designs.      

 

I was in fear of detracting from topical matters so early in a thread.  So resorted to an easy to dismiss joke.  Noting I was very impressed with the quite visible no-nonsense display of high quality work was probably needed.  Thank you for bringing Atma-Sphere to my attention. 

[gmgraves]

21 hours ago, Johnseye said:

I think I can speak for the majority of this community when I say we're all in a constant search for improving our two channel sound.  About a year and a half ago I began an endeavor to focus on rebuilding a two channel system.  I've made many changes since then.  This most recent being the addition of a preamp.  I have a Marantz prepro that I use for multi-channel and my Audio Alchemy DAC has a pre.  Both do a good job.  I was very happy with how the AA sounded, but I had read quite a bit about using a tube pre and I wanted to see what that was all about.  So I began a several month effort to audition a handful of respectable tube pre's and tried to stay around the $5k range.  During this time I learned about Benchmark's release of their DAC3 and because I've found their AHB2 amp to be the quietest amp I've ever heard, after talking to Rory at Benchmark I threw that in the mix as it has a pre.  Then a local dealer told me about the upcoming Anthem STR Pre, another solid state.  He had a new Anthem integrated with a similar design concept so I gave that a listen as well.  There are macro changes we can make to our system and there are micro changes.  After the choice of speakers or headphones, the preamp can make this biggest difference.  That said, I find it interesting that there is no section in this forum for the likes of preamps or amps, which is why this review landed in the General section.  If others would like to contribute to this thread by adding their own preamp review, including any I've discussed, I'm good with that.

 

Testing was done in both analog and digital realms.  I'd be happy to share the various cables I swapped out, turntable and music sources if requested but otherwise won't get into that in this first post.

 

The contenders:

 

Rogue Audio RP-5 - $3.5k

Backert Labs Rhumba 1.2 - $3.4k

Backert Labs Rhumba Extreme - $5.5k

Benchmark DAC3 HGC - $2.2k

Anthem STR Integrated - $4.5k

Audio Research LS28 - $7.5k

Atma-Sphere MP-3 - $5k

Atma-Sphere MP-3 with phono stage and Vcaps - $7k

 

 

Rogue RP-5

http://www.rogueaudio.com/Products_RP5.htm

This was the first tube pre I took home.  It's been a while so my recollection won't be as detailed as the other pre's.  I plugged it in, let it warm up and man was I disappointed.  I had heard so much hype about tube pre's and while I've heard them at Axpona and in stores, that was with completely different equipment.  There is one caveat to this experience.  The RP-5 doesn't have balanced outs so I had to use my older Emotiva amp as the Benchmark only has balanced in.  Noise level from the Emotiva aside, the RP-5 sounded flat.  The dimensionality shrunk by comparison to the AA pre.

Backert Labs Rhumba 1.2

http://backertlabs.com/to-purchase/

The Rhumba sounded much better by comparison to the Rogue.  There was more dimensionality as well as very good top and bottom end clarity and oomph.  It was more in line with what I was looking for, but it still sounded a bit like solid state.  I also had the Benchmark DAC3 and ARC LS28 at the same time so was able to compare all back to back.  The Rhumba's remote is a simple volume control, that's all.  Andy, Backert's president was very communicative.  When I gave him my initial feedback he sent me out another set of tubes to try.  When you get to my comments on the ARC you'll understand why.

 

 

Backert Labs Rhumba Extreme

Very similar to the 1.2.  If I were to describe the difference it would be that the Extreme is slightly cleaner sounding.  The $2k is probably better spent elsewhere.

 

Benchmark DAC3 HGC

https://benchmarkmedia.com/collections/digital-to-analog-audio-converter/products/benchmark-dac3-hgc-digital-to-analog-audio-converter

The Benchmark sounded extremely clean.  It paired up nicely with the AHB2 from that perspective.  The remote is solid and everything is very well built.  It was however very similar to my AA DAC in almost every respect.  The only real difference was in the clarity which contributed to a bit more dimensionality.  But it was clinical to my ears and not in the direction I wanted to go.  My entire two channel system up to that point was built around clean and clear.  Now I needed to add some body and musicality, not more crispness.  If I were to choose between the AA and the DAC3 I'd probably take the DAC3, but the improvement was so slight it didn't justify keeping it.

 

Anthem STR Integrated

https://www.anthemav.com/products-current/model=str-integrated-amplifier/page=overview

I won't go into this one too much as I didn't give it that long of an audition.  It's a decent sounding solid state amp.  Where it shines is in its room correction which I didn't setup.  It also allows for a more seamless subwoofer integration.  If I were looking for a new solid state pre I would strongly consider the upcoming STR for these features.  From a sound quality perspective without the room correction it sounded flat and 2 dimensional.  The reason why I didn't use the room correction is because it was setup for the store and they didn't give me the mic.  Not a good way to audition a pre.

 

Audio Research LS28

http://www.audioresearch.com/en-us/products/preamplifiers/ls28

I had been sharing my plans and experience with @Ralf11 in another thread and he recommended I give ARC a listen.  While I had heard some things about ARC I hadn't given them serious consideration.  Many of the commentaries in reviews I read people had tried ARC, then moved on to something else.  Audio Research has been around for a while.  I found a local dealer and the owner agreed to let me take an LS28 home.  His store was about an hour and a half away but he lived about 45 minutes from me so we met close to his home.    I hadn't even asked about the price yet.  When he told me what it was I was thinking, well this is about double what I want to spend.  I thought I'd give it a listen but couldn't imagine taking it much further.  When I got it home and started to listen I thought wow.  Just wow.  This is what people were talking about when they hear something good from a tube pre.  The soundstage the LS28 creates is big.  Not overwhelmingly big,  but it made other pre's I'd listened to small by comparison.  It was like when I heard Magnepan for the first time.  A large, full soundstage.  Then there was the fullness and balance of the sound.  A full midrange combined with excellent highs and lows to probably the best combined tonality I'd ever heard.  This is what may lead to the next thing I noticed and that was the timing.  That blew me away.  I was hearing the timing between musicians where their changes were clear as day.  This I had never heard in a system.  Mick, the owner of the store who lent me the LS28 said he thought it was incredibly close in sound to their Ref 6 and that this was a new step up for Audio Research.  I then went out and read whatever reviews I could find on the LS28 and others were confirming a lot of what I heard.  It's an incredibly light unit by comparison to the other pre's.  I think the chassis must be made out of a lightweight aluminum.  The remote is hefty and solid however.  Unlike the Backert remote it can do everything the interface can.  I could go on about this pre and likely will later, but this was my new standard.

Atma-Sphere MP-3

http://www.atma-sphere.com/Products/#MP-3

Ralph, the owner of Atma-Sphere spent a couple hours over multiple calls chatting with me about technical details.  He's an incredibly patient and knowledgeable engineer.  Unfortunately when I receive the MP-3 it was out of phase.  I couldn't get a center image, so he recommended I swap polarity on a single speaker.  That did it.  There were a couple other issues I clarified with him and he eventually sent me out a replacement which I just got today.  This time I opted for full Vcaps as well as a phono stage on his recommendation.  I've had the other MP-3 for a few weeks now so plenty of time to compare it to the LS28, which I still have thanks to Mick's graciousness.  The MP-3 is the closest thing I've heard to the LS28 and by some characteristics it's better.  It carries the same soundstage which I found very interesting.  The coincidence is that ARC, Atma-Sphere and Magnepan are all based in the Minneapolis-St. Paul area, and they all have amazingly similar soundstages.  What the MP-3 does better, and only very slightly, is in its clarity.  Instruments are a little more defined, maybe a little brighter.  However the MP-3 doesn't have the same feeling of timing that the LS28 has.  Perhaps there's a slight lacking in the midrange, I'm not sure.  The replacement MP-3 I received also has a remote where the first one didn't.  The remote is the exact same one as the Backert, just volume.  There is an actual belt motor that turns the volume knob inside of the MP-3.  This is by design to keep with their minimalist approach to the circuit board.  Unfortunately I've run into some issue with this version of the MP-3.  The volume control has steps for each level and the remote doesn't seem to match with those steps.  I will also hear a significant amount of white noise when the volume is in between steps and the remote volume lands right on those spots sometimes.  Another issue I've found is that this version has a significant amount of noise when idle.  It's possibly due to the phono stage as when that's active there's much more hiss.  But the linestage also has more noise than the other MP-3.  I'm not sure what the issue is, but it's a shame because this is a really nice sounding pre otherwise.  It's also fully balanced and has a patent on that engineering.  Take a look at the website for full details.

 

 

And the winner is the Audio Research LS28.  Thanks Ralf.  Mick has extended his offer and allowed me to keep his store's model until mine is built and arrives.  He'll stop by when it's ready to sit down for a listen in my theater room where this is all setup.  I've asked him for some advice on any additional room treatments and equipment positioning.  I've built all my current room treatments with acoustic cloth and duct dampening insulation.  I've had a pro come by and calibrate my theater equipment, but never from a 2 channel perspective.  Mick was trained by some well known room acoustic engineer in Germany who's name I've forgotten so I'm looking forward to his opinion.

 

During the past few months I've also played around with moving the pre away from the amp and speakers using a balanced run.  For some reason when I did this I thought the sound closed up a bit.  I went from 1m XLR to 4.8m between the pre and amp, but this allowed to shorten the length of my current phonostage to pre single ended interconnect.  It could be that the new XLR cable is from DH Labs where the previous is Audioquest.  Ralph at Atma-Sphere included a 5m XLR pair of Mogami cables with Neutrik connectors, and that sounded closer to the Audioquest cables.  This is another area where more testing is needed.

Have you listened to the Parasound JC-2? It was designed by John Curl and is considered State-of-the-art for about $5k.

[mourip]

9 hours ago, Speed Racer said:

 

http://www.superbestaudiofriends.org/index.php?threads/microzotl-2-0-review.1750/

 

Kind of a ho-hum review. The MZ2.0 ramps up well with a really clean front end so perhaps that is what was lacking on SBAF.

 

Although it was initially meant to be a headphone amp and can be used as a very low power speaker amp it shines as a preamp. I use it with an LTA Z10 EL84 amp.

 

Try these reviews to get more opinions.

 

http://www.theabsolutesound.com/articles/david-berning-microzotl20-personal-amplifier/?page=2 (Dick Olsher)

 

http://www.enjoythemusic.com/magazine/equipment/1015/David_Berning_microZOTL_2_Headphone_Amplifier_Review.htm

[Johnseye]

1 hour ago, gmgraves said:

Have you listened to the Parasound JC-2? It was designed by John Curl and is considered State-of-the-art for about $5k.

 

I briefly considered listening to one. I almost bought an A21 amp and would have had I not discovered the Benchmark. I wanted to stick to tube pre's and the only reason why I tried the DAC3 was because I really wanted to hear how it paired with the AHB2, and the Anthem because I've been looking for a better way of blending my sub for 2.1.

[Johnseye]

On 9/21/2017 at 12:01 AM, Ralf11 said:

Thanks John.  

 

What was in front of the pre-amps?  i.e. digital or analog, or both?

 

BTW, I think Audio Research may put dampening material on the cases in strategic areas.

 

I also noticed an improved "sense of pace" in the music when going from a Sonic Frontiers Line One (with old tubes) to the LS25 Mk II.  I'd always thought it was BS when the term was used by Stereophile's reviewers, yet there it was.  How it does that I dunno, but it is a descriptive term for whatever is going on.

 

PRAT

[gmgraves]

16 hours ago, Johnseye said:

 

I briefly considered listening to one. I almost bought an A21 amp and would have had I not discovered the Benchmark. I wanted to stick to tube pre's and the only reason why I tried the DAC3 was because I really wanted to hear how it paired with the AHB2, and the Anthem because I've been looking for a better way of blending my sub for 2.1.

 

Luke Manley of VTL makes a couple of very good, very capable tube pre-amps. Don't forget to look at those. Also Audio Research preamps do have tubes, but traditionally, their line-outs are solid state. 

[Johnseye]

2 hours ago, gmgraves said:

 

Luke Manley of VTL makes a couple of very good, very capable tube pre-amps. Don't forget to look at those. Also Audio Research preamps do have tubes, but traditionally, their line-outs are solid state. 

 

VTL is another I'd never heard of, thanks.

 

What do you mean ARC's line outs are solid state?

[Speed Racer]

49 minutes ago, Johnseye said:

 

VTL is another I'd never heard of, thanks.

 

What do you mean ARC's line outs are solid state?

 

I think he meant that most of their preamps are solid state.

[Johnseye]

5 minutes ago, Speed Racer said:

 

I think he meant that most of their preamps are solid state.

 

I don't think they make any solid state preamps

[Speed Racer]

12 minutes ago, Johnseye said:

 

I don't think they make any solid state preamps

 

I didn't research it, I just tried to figure out what he was trying to say.

[arcman]

So you were pleased with the preamp section of the Benchmark? Im debating seperate preamp or combo preamp dac

[Speed Racer]

The preamp in a DAC is never going to be as good as separate quality preamp component. 

[gmgraves]

1 hour ago, Johnseye said:

 

VTL is another I'd never heard of, thanks.

 

What do you mean ARC's line outs are solid state?

 

VTL is Vacuum Tube Logic. They are very respected name in tube audio electronics and are a spin-off of Manley Audio. By the statement that ARC's line-outs are solid-state, I mean that although they have tubes in them, the final stage of ARC preamps is transistorized. IOW, they aren't completely tubed. So if it's pure tube you're interested in, ARC is probably not what you're looking for.

9 minutes ago, Johnseye said:

 

I don't think they make any solid state preamps

 

I don't know if they make any 100% solid state equipment any more or not, but traditionally, the final output stage of ARC preamps have been transistorized. I can't verify that the REF-6 has a solid-state output stage or not, as I cannot find any mention of it or a schematic online, but it is traditional for them. Again, to make sure, contact ARC directly. 

[pkane2001]

18 minutes ago, Speed Racer said:

The preamp in a DAC is never going to be as good as separate quality preamp component. 

 

Never? How can you be so sure that adding one more complex, active component with additional interconnects in the path of analog signal will improve signal quality?

 

[Speed Racer]

24 minutes ago, pkane2001 said:

 

Never? How can you be so sure that adding one more complex, active component with additional interconnects in the path of analog signal will improve signal quality?

 

 

You go ahead and get a DAC with a built-in preamp if it makes you happy. I'll be using a tube-based preamp and be happier for it.....

[pkane2001]

11 minutes ago, Speed Racer said:

 

You go ahead and get a DAC with a built-in preamp if it makes you happy. I'll be using a tube-based preamp and be happier for it.....

 

I've not had a separate preamp in my systems for about 25 years. Can highly recommend trying this with the right DAC and amp combo.

 

[mourip]

1 hour ago, Speed Racer said:

The preamp in a DAC is never going to be as good as separate quality preamp component. 

 

That has been my experience also. I have done it both ways and many times. I found that a separate active preamp improves over using the output stage of most DACs. Usually the benefits are increased dynamics and a more convincing soundstage. Perhaps it is the dedicated power supply or better impedance matching.

 

It is also possible that the keyword here is "quality :-)