Blind Test Results: Benchmark LA4 vs Conrad Johnson Tube Preamp

[MattHooper]

It could be what is happening. If you wanted to bother you could take the output from the various ways of connecting the preamps and measure it with an ADC. Use some simple test tones and see what results you get with different configurations. Running the CJ lower and then going thru another preamp would worsen SNR, dynamic range and SINAD somewhat. Whether it is audible or not hard to say without more info.

Righto. I'm probably too lazy to get around to doing that. I tend to get the gumption up for such stuff, but then get tired of it and "just wanna listen to music."
But thanks for the suggestions. They are there if I want to take advantage in the future. Cheers.

 

[MattHooper]

Update: mere musings..

I've been switching between my LA4 and CJ tube preamp for a long time now. Fun having the flexibility to switch with a click on the remote between the Benchmark only, or putting the signal through the CJ, for instant comparisons.

I've decided that if I had to own only one, it would be the CJ tube preamp. Tonight's listening was typical. I was listening to some everything but the girl tracks, one starting with panned acoustic guitars split to L/R and then male vocals enter, doubled, voice split L/R as well. The Benchmark DAC2L going through the Benchmark preamp: utter clarity. Super "transparent" sounding as the golden ears would have it. But the voices sounded more "recorded/artificial" slightly crispy in the sibilance, and sort of "see-through." Like I have a giant X-ray on the recording and I'm seeing "through" each instrument to the ones behind it.

Click to the CJ preamp and...the vocals fill out with more body, now they sound more solid, sibilance now sounds more natural...just sounds more like real voices occupying the space around the speakers. Acoustic guitars gain more body, drums more solidity and "snap" on the snare etc. Since I seek that sense of body and warmth to sound, I just find it too addictive to give up the characteristics the CJ seems to add vs the Benchmark. (I would say similar things about vinyl in my system vs digital, to generalize there tends to be some added body, warmth, texture to the sound. So the most solid/dense sound I experience tends to come from the combination of a good vinyl pressing with all tubes in the system. I can understand why many find vinyl 'n tubes seem to go together so well).

Luckily I don't have the choose, and will be keeping the Benchmark, since I also still appreciate what it brings to the table.

 

[Short38]

One of the best threads I’ve read on ASR. Clear descriptions of the perceived differences between the two preamps and an even handed discussion of the pros and cons. Thank you.

 

[MattHooper]

One of the best threads I’ve read on ASR. Clear descriptions of the perceived differences between the two preamps and an even handed discussion of the pros and cons. Thank you.

Cool, thanks!

People generally aren't too big on subjective description around here, so it's nice to see someone enjoys that aspect of the thread too.

 

[ahofer]

the more one has the opportunity to listen to live music the more one might appreciate what the tubes are doing.

I’ve had the opposite experience.

EDIT: not saying so just to be contrary. My primary live reference tends to be orchestral and chamber music, and I've found strings don't sound right (accurate) through some tube amplifiers. My presumption is that the added harmonics are doing it, but I could also be imagining things.

 

[pkane]

I’ve had the opposite experience.

Same here. Spent some time trying out C-J pre- and amp equipment and found it to add grunge to the sound, making it fuller ... but to me, more unnatural and less transparent. And this was even before I got into measuring these things, so, mostly subjectively speaking

 

[MattHooper]

Same here. Spent some time trying out C-J pre- and amp equipment and found it to add grunge to the sound, making it fuller ... but to me, more unnatural and less transparent. And this was even before I got into measuring these things, so, mostly subjectively speaking

And I can imagine that you might have the same preference against the CJ preamp in my set up too. It definitely comes with some compromise.

 

[raindance]

I’ve had the opposite experience.

EDIT: not saying so just to be contrary. My primary live reference tends to be orchestral and chamber music, and I've found strings don't sound right (accurate) through some tube amplifiers. My presumption is that the added harmonics are doing it, but I could also be imagining things.

Interesting. I have some recordings where the violins are a bit harsh and my AMC tube preamp smooths them and makes them more "syrupy" and easier on the ears. But it isn't a truthful rendering of the recording; better recordings definitely sound better with a low distortion preamp (or a passive - I won't call it a preamp because it isn't, just a volume control ).

 

[DMill]

Update: mere musings..

I've been switching between my LA4 and CJ tube preamp for a long time now. Fun having the flexibility to switch with a click on the remote between the Benchmark only, or putting the signal through the CJ, for instant comparisons.

I've decided that if I had to own only one, it would be the CJ tube preamp. Tonight's listening was typical. I was listening to some everything but the girl tracks, one starting with panned acoustic guitars split to L/R and then male vocals enter, doubled, voice split L/R as well. The Benchmark DAC2L going through the Benchmark preamp: utter clarity. Super "transparent" sounding as the golden ears would have it. But the voices sounded more "recorded/artificial" slightly crispy in the sibilance, and sort of "see-through." Like I have a giant X-ray on the recording and I'm seeing "through" each instrument to the ones behind it.

Click to the CJ preamp and...the vocals fill out with more body, now they sound more solid, sibilance now sounds more natural...just sounds more like real voices occupying the space around the speakers. Acoustic guitars gain more body, drums more solidity and "snap" on the snare etc. Since I seek that sense of body and warmth to sound, I just find it too addictive to give up the characteristics the CJ seems to add vs the Benchmark. (I would say similar things about vinyl in my system vs digital, to generalize there tends to be some added body, warmth, texture to the sound. So the most solid/dense sound I experience tends to come from the combination of a good vinyl pressing with all tubes in the system. I can understand why many find vinyl 'n tubes seem to go together so well).

Luckily I don't have the choose, and will be keeping the Benchmark, since I also still appreciate what it brings to the table.

I’m curious. Do you listen one more than the other? I have a theory that we train our brains to enjoy a certain sound over another with repetition and those preferences become the standard with how we judge gear.

 

[MattHooper]

I’m curious. Do you listen one more than the other? I have a theory that we train our brains to enjoy a certain sound over another with repetition and those preferences become the standard with how we judge gear.

I really go back and forth. I might listen with the Benchmark for a week, the CJ another week (or either for longer), or I might even flip between them over a few albums in a single night. It's tempting because it's just a click of a button on the remote "I wonder how this sounds on the CJ" or whatever.

But I can see merit in your theory. For instance, one constant in my system has been my CJ tube power amps. And IF, for sake of argument, those amps do have a certain sound in my system, then since I've used them for so many years I may have oriented my expectations that way. Though I'm also constantly listening to the sound of live voices and instruments, as an ongoing reference. Plus, I also listen to music a lot on my home theater surround system, which sounds quite different, yet I love that sound too.

 

[MattHooper]

Interesting. I have some recordings where the violins are a bit harsh and my AMC tube preamp smooths them and makes them more "syrupy" and easier on the ears. But it isn't a truthful rendering of the recording; better recordings definitely sound better with a low distortion preamp (or a passive - I won't call it a preamp because it isn't, just a volume control ).

I don't doubt your personal experience/preference in that regard.

It's a common proposition that even if something adds some pleasing distortion, like a tube preamp, that may perhaps help with some lower quality recordings. But with a really good recording you don't need it, and adding any distortion would only detract from the sound quality.

Yet that hasn't been my experience. I have found the tube amp introduces certain characteristics that I like no matter the recording. I think there is just an overall deficiency in recording and stereo sound reproduction that tends to leave voices and instruments less rich than their real life counterparts, thinner, and the stereo illusion is generally gossamar - see through. So even on the best audiophile recordings, I find the tube amp introduces more body, density, warmth, richness, textural presense, carves out the sonic images a bit more vividly...it just pops more and sounds a bit more "like real life" to me. The sound takes a *very small* hit in ultimate neutrality and transparency, but it often seems more than made up for with the positives. Totally a subjective call, of course. Because sometimes I can very much enjoy the Benchmark presentation, which gives a tiny bit more grain-free subtlety and insight in to the recording. So I use the Benchmark when I want to have the sensation of "hearing really deeply in to a recording" and the CJ when I want it to feel a bit less like a recording, more hearing in to a space where musicians are playing. (Again...we are talking very subtle changes, that my audiophile attention turns in to large subjective significance).

 

[DMill]

I don't doubt your personal experience/preference in that regard.

It's a common proposition that even if something adds some pleasing distortion, like a tube preamp, that may perhaps help with some lower quality recordings. But with a really good recording you don't need it, and adding any distortion would only detract from the sound quality.

Yet that hasn't been my experience. I have found the tube amp introduces certain characteristics that I like no matter the recording. I think there is just an overall deficiency in recording and stereo sound reproduction that tends to leave voices and instruments less rich than their real life counterparts, thinner, and the stereo illusion is generally gossamar - see through. So even on the best audiophile recordings, I find the tube amp introduces more body, density, warmth, richness, textural presense, carves out the sonic images a bit more vividly...it just pops more and sounds a bit more "like real life" to me. The sound takes a *very small* hit in ultimate neutrality and transparency, but it often seems more than made up for with the positives. Totally a subjective call, of course. Because sometimes I can very much enjoy the Benchmark presentation, which gives a tiny bit more grain-free subtlety and insight in to the recording. So I use the Benchmark when I want to have the sensation of "hearing really deeply in to a recording" and the CJ when I want it to feel a bit less like a recording, more hearing in to a space where musicians are playing. (Again...we are talking very subtle changes, that my audiophile attention turns in to large subjective significance).

I’ve also experienced this with a Yamaha SS vs Cary tube integrated. Imagine a Thanksgiving turkey dinner where every component is separate. The turkey, potatoes, stuffing, and gravy. That is my Yamaha. I taste every ingredient. My Cary is all of it in a pile, and it tastes better sometimes. Mashed potatoes or turkey without gravy can be bland. I also want to be very clear, I completely understand the Yamaha is more what it should taste like. Apparently I’m hungry and forgive the analogy.

 

[Short38]

Since the treatment of various types of music runs through this thread, I’d be interested in thoughts about massed first violins in orchestral recordings. I spent a lot of time and money and returns trying to figure out why the opening of the second movement of the Rachmaninov second symphony (Askenazy Decca London) sounded as though there was a pre-echo and “fuzz/tizz” in the massed violins. Same with nearly every classical cd containing massed violins. Violins sound woody and sweet not fuzzy/tizzy. Could someone stream that recording and tell me what you hear? (I currently have a Rotel tribute cd player feeding an SMSL es 400 dac balanced to a Yamaha as2200 driving paradigm founder 80s. Prior stuff included Marantz 30s and Rotel diamonds driving Dynaudio Special 40s.) “Simple” music, jazz and rock all always sounded fine. Thanks for any thoughts.

 

[MattHooper]

Since the treatment of various types of music runs through this thread, I’d be interested in thoughts about massed first violins in orchestral recordings. I spent a lot of time and money and returns trying to figure out why the opening of the second movement of the Rachmaninov second symphony (Askenazy Decca London) sounded as though there was a pre-echo and “fuzz/tizz” in the massed violins. Same with nearly every classical cd containing massed violins. Violins sound woody and sweet not fuzzy/tizzy. Could someone stream that recording and tell me what you hear? (I currently have a Rotel tribute cd player feeding an SMSL es 400 dac balanced to a Yamaha as2200 driving paradigm founder 80s. Prior stuff included Marantz 30s and Rotel diamonds driving Dynaudio Special 40s.) “Simple” music, jazz and rock all always sounded fine. Thanks for any thoughts.

Sorry this isn't to help with your request about that particular recording.

But massed strings are, for me, maybe the hardest thing to get right on a sound system. I think this could be partially due to my playing keyboards since the 70's on. As keyboards progressed from analog to sample-based sounds, so in the 80's we were getting actual samples of strings for stringed instruments. Especially on the less heroically expensive keyboards, there was a very obvious "sampled not real" quality when you played strings - very thin and sort of lacking harmonics, coarse in texture. They just really sounded like you were triggering bad samples of strings. They got better over time, but for me rarely convincing.

Also, massed strings seem to present a particular challenge to recording/reproduced sound. Especially in the upper frequencies, they can get right in to the frequency ranges that many speakers seem to struggle with presenting naturally. So instead of it sounding like a whole mass of bowed instruments, organic, they congeal in to a thinner, homogonized "chalky" hiss of sound. Which remind me of those old keyboard samples. So when I hear strings sound unequivocally like real strings, that's always hugely impressive and gratifying.

As to the tube preamp/Benchmark take on strings: often the tube preamp I find thickens out the strings and slightly emphasizes the texture, which can make strings sound more solid, present and real. On the other hand, with the benchmark, on a really good recording I can hear the fine textures more of the individual bows on strings, which is convincing and gratifying as well. So, just depends on which presentation I feel like.

 

[Short38]

Your description using the terms chalky/ homogenized/ covers what I hear. I think the issue starts with the microphone but do not know enough about recording technology to be certain. One of the early Stereophile test cds featured j Gordon Holt reading a script receded by a series of microphones. Big difference among them from my memory. In photography lens testing includes resolution as a key measure. I gather that is not a term used in ASR but there may be utility in trying to figure out how to measure instrument differentiation in recordings. I appreciate your characterization of the “phenomenon” I have experienced.

 

[MaxBuck]

Matt, in all honesty you remind me of my friend who owns two automobiles: a Jeep Renegade and a Ferrari. I don't get it, but then the point isn't that I get it. The point is that he gets it, and that you get it.