AB comparison

[carlosfm]

I think you guys forget one thing: If my eye likes what it sees it's an advantage. Visual impressions are very important. If we have a black box, it's more difficult to pick the difference.

Ahaha!
That's funny.
Some people may connect aesthetics to sound quality.
I don't.
Even a bunch of wires and boards laying on the floor may give miracle sounds.

Peranders, you're talking to DIYers...

 

[Raka]

Carlos,

Have you AB'd your gainclone? Based on what do you think a gainclone will beat a denon?

The caps of my clone are very standard electros, they were about half an euro each. Could be this the reason? I've read comments of builders with standard caps, and they also praise the 3875. How much can be expected from a Panasonic?

Peter,
Nope, are there no LMchips in the denon

 

[JOE DIRT®]

I am going to be interested in hearing a GC compared to my current equipment also....as it stands right now I have zero invested in it but time...what keeps me motivated is this forum and the Rep at national.....that was a little hint for the members here....you would be surprised if you gave some feedback on how you have utilised their product

DIRT®

 

[SY]

The most difficult thing is to adjust the volume equally if you don't use a signal generator to measure the gain. Even the smallest difference makes a difference substantial.

Normally, that's true, it's the hardest, fiddliest, most tedious thing to do. And because of that, most informal tests are fatally flawed. You really need, besides the signal generator and a high-resolution voltmeter, a precision attenuator. If you don't get the levels matched to better than 0.1 dB, your test will almost always favor the louder amp, with the test subjects perceiving not "louder," but rather "clearer," "more open." This has led a lot of people down the garden path.


Christer: Thresholds for different aromas and flavors vary greatly among individuals. And that's a different thing than sensory memory. For example, I can taste a wine and give you a pretty accurate estimate of alcohol, residual sugar, and acidity. My cooking partner can't do that, but he'll tell you what the wine is and where it's from to a surprising accuracy. He REMEMBERS the markers of certain vineyards and regions to an extent that I just can't.

I note though that we always do analytical tastings blind, using various protocols.

 

[carlosfm]

Carlos,

Have you AB'd your gainclone? Based on what do you think a gainclone will beat a denon?

The caps of my clone are very standard electros, they were about half an euro each. Could be this the reason? I've read comments of builders with standard caps, and they also praise the 3875. How much can be expected from a Panasonic?

Peter,
Nope, are there no LMchips in the denon

Raka, my good old Nad amp goes to my son's bedroom.
I didn't exactly did A/B tests, but the difference is so great anyone who hears to my GC gets amazed.
I did tests with my Nad against my GC, but not pure A/B.
I went to my father's house one day with my GC.
We listened to some well recorded CDs that we know very well and compared his AMC amp with my GC.
Let's say it's another world.
My father whants to make one too, he is amazed.
I already made the two channels for him, and he's waiting for the toroid to arrive.
When I put something playing to demonstate a device I like to put some music that the person knows very well.
It's easier.

As for the caps, I made mine with cheap caps too.
Nothing too fancy, nothing too ordinary.
Some Daewoo 1000uf 105º temp. rating caps.
The price is about the same as yours.
Bypassed with 100nf polyesters.
It's important to bypass if you use cheap caps.
Take a look to my "PC Gainclone" thread for some pictures of my GC.

I say a GC beats your Denon AV amp based on the fact that I have serious doubts your Denon is better for music than my Nad Monitor Series stereo amp.

And one thing that you can try is to listen to a good vinyl record while testing, because listening to a good CD on a cheap (don't take me wrong) DVD it's not good.
You have a better vinyl front-end than CD.
You would be surprized if you changed the NE5532 op-amp on your phono preamp to a Burr-Brown OPA2228.

 

[mothman]

I have A/B my gainclone against several very fine production amps.
I built my clone with all premium parts,Black Gates,Dact attenuators,Mills resitors,Plitron trafo,Schottky diodes,Cardas wire and connectors.All parts carefully mounted in a high quality,rigid aluminum case with suitably sized aluminum heatsinks and vibration control.
This spare no expense clone cost me about $700 in parts.Parts quality that you will rarely if ever see in many very expensive production amps and yes I've owned and been inside several.
I'm also an experienced acoustic guitar player and am very familiar with the finer points of selecting,setting up and repairing high quality instruments.
My listening test and comparisons tell me that a 'HIGH QUALTY'gainclone can and does compete with excellent solid state amps in the $2000 to $4500 range.
I now use mine exclusively and have no desire to spend any more thousands on high end gear.

 

[Peter Daniel]

Has anyone out there AB'd any gainclone? Really?

Can you A/B two violins?
I don't A/B amps and other equipment because that doesn't tell me anything. You just compare the sound in a brief moment between switching and it is artificial. For me the amp is like a musical instrument and I prefer to listen to it and finding my reaction to the sound presented.

Sometimes, in case when equipment varies much, I know right away that this is not the musical presentation I'm after. Sometimes it takes a long time to decide which sounds better. Sometimes the presence of other people helps, because they make remarks, you wouldn't think about.

I can have 10 GC built, ea. with a small difference, (resistor, wire, insulating pad, capacitor) and I just switch them in a system and listen. The difference is usually very obvious. Like last time when I compared 250k and 300k feddback resistor.

I also improved my initial design by substituting parts and achieving even better three dimentional sound. Incidentally, I was not much impressed with 1000u/50V BG N caps ($74 ea.) for PS filtering. They were only a bit more smoother and slightly more laid back that comparable standard BG grade and some people actually preferred standard version of the cap.

In GC every little detail has big influence on sound, just changing umbilical cord from Kimber to Cardas brought another "dimension" to the sound. Also the way the casing is done and PS caps are damped, even insulating pad influences the sound.

So you might say that this amp is better or worse than the other, but I can built 10 GC and ea. will sound different. All I have to do, is make my choice

Have you spent 8 hours a day trying to get the damn passage in tune with the correct sound, and shades, and dynamics, and tempo, and phrasing, and style and listening to the complete picture with the others musicians?

I was listening for 8 hours to the caps in my crossover, listening to few damn CDs, looking for the correct sound, and shades, and dynamics, and tempo, and phrasing, and style and listening to the complete picture with the others.

 

[SY]

I was listening for 8 hours to the caps in my crossover

Did they have anything interesting to say?

BTW, there's nothing that restricts subjective, controlled, sensory testing to short passages. In the same way, when I run people through my wine sensory panels, they can take as long as they like. I don't stand there with a stopwatch and yell, "Put that glass down and pick up the next one!"

 

[carlosfm]

I was listening for 8 hours to the caps in my crossover, listening to few damn CDs, looking for the correct sound, and shades, and dynamics, and tempo, and phrasing, and style and listening to the complete picture with the others.

When things make "click" and the sound quality is really good, I can't stop listening!
Enjoy the music.

 

[Peter Daniel]

Did they have anything interesting to say?

BTW, there's nothing that restricts subjective, controlled, sensory testing to short passages. In the same way, when I run people through my wine sensory panels, they can take as long as they like. I don't stand there with a stopwatch and yell, "Put that glass down and pick up the next one!"

Our approach and philosophy regarding sound perception might differ, but it doesn't stop us from sharing our experiences, right?

When things make "click" and the sound quality is really good, I can't stop listening!
Enjoy the music.

If it doesn't click, I have to listen even longer

 

[SY]

Our approach and philosophy regarding sound perception might differ, but it doesn't stop us from sharing our experiences, right?

Well, of course, but it needed to be pointed out that your objection to controlled testing is not inherent. Nor is it a factor in well-designed tests. Just because someone has built a crummy tube amp, it doesn't follow that tube amps generically have the same defects.

 

[Peter Daniel]

Well, of course, but it needed to be pointed out that your objection to controlled testing is not inherent. Nor is it a factor in well-designed tests. Just because someone has built a crummy tube amp, it doesn't follow that tube amps generically have the same defects.

Well, I say it again, listening to music and A/B testing is different. Even when testing, I decide on a certain choice, it doesn't mean that I will approve or like it after prolonged listening. So both approaches are important and have appeal to certain individual preferences. If A/B makes your day, it's alright with me. I won't argue about superiority of any method. But I tried it and it simply doesn't work for me. It was also done in the beginning of my audio journey as I thought it was the simplest thing to do, just switch the signal from one source to the other as fast as you can and try to find a difference. When I look back at those days, a smile comes to my face

 

[carlosfm]

If it doesn't click, I have to listen even longer

That's a good one.
Deam, I can't stop laughing.

 

[Raka]

Carlos,

I know my DVD isn't hi-end , and the differences are more easily detected with my TD, but not big anyway. I will try the 2228 because BB was kind enough to send me pair

Peter,

Haha, AB two violins (good one). In spite of the similarities, when you play the violin you are the signal generator, the amp, the wiring (bow) and the listener, and the violin is only the speaker (bassreflex, btw). So there are even more items to consider.
Yes, I could agree that AB is artificial, but you will have to agree that AB can give some information too, can't it? If two amps are obviously different, this should appear in a AB most of the times, right? Maybe a long listening test make you to enjoy more an specific amp, but those "big" differences, those "obvious" improvements, should be detectable by AB
I'm also finding by myself things that you said in your post, like the presence of other people makes you less prone to artificial biasing to yourself.
I take the opportunity to ask you something (as I'm also a fan of your amps and building skills) Do you think that covering all the amp (well, the chip and caps only) with silicone or hot glue would damp the amp?, damp the amp, let's sing together, damp the amp, dampd-amp, damp the amp damp-d-amp (now the battery at countertime) punchin, punchin, damp, punchin, theamp... Where is the bassist!?!?!?!? Hey you, stop drinking and come here!! bum, bum, bum, punchin, damp, chinpunchin, the amp, bumm, bumm, This sounds good, let's phone Hetfield to put some guitars and record this...

So you know what is to work the ear 8 hours a day, I admire you.

Mothman,

Thanks for your comments and congratulations for your amp, that's what I was hoping to hear. To which gear did you strictly AB'd?


SY

But you stop them to drink the complete bottle each type of wine, don't you?


Has somebody else AB'd a Gainclone? I sincerely respect and understand the people who doesn't catch a difference in an AB but still prefer A to B, but I'd love to hear your comments about an AB.
I will try to report a AB of my amps. If I have time this evening, I'll try to write my opinions on a audition. In the meantime, please listen you all to the second part of the first violin concerto of Sostakovich (preferable by Oistrakh)

 

[analog_sa]

Raka

Careful with excessive damping - it can kill the sound. Especially with hot glue where the dielectric constant/conductivity may not be well known. I've tried potting audio circuits with epoxy in the very distant past with disastrous effects.

peter

 

[Raka]

Thanks for the advice.
Now the pins of the chip are covered with a small ball of silicone, just to avoid shorts or broken pins, since the caps are kind of floating in the air.
What do you mean "kill" the sound? What "disastrous" results: dielectric breaking or smeared output?

 

[Peter Daniel]

There is an interesting article on resonances http://www.soundstage.com/maxdb/maxdb111998.htm

Here are some info from there. I can totaly agree with the idea of redistributing resonances and not completely eliminating them to achieve best sound signature:

>>You can take identical components, build identical circuit boards and install all the parts in different cases with different hardware and the resulting components will sound different. There is no way to stop this. The reason the sound will change is that mechanical resonances affect sonics -- what you hear when you listen to your system is affected by how the manufacturer dealt with mechanical resonances in the products you use.

The key is uniform distribution of mechanical resonances
Products with "clumped" resonances will never sound as good as products where the designer took the time to distribute resonances across the audio frequency spectrum as much as possible. However, there will always be some limitations to how effectively you can spread out resonances. Doing nothing is rarely the right answer.
Every change made will change the sound heard, but that sound is not necessarily going to be better. Tuning a component is filled with pitfalls. The designers who do pay attention to mechanical resonances are going to end up with a more sophisticated, refined sound that will elude products which are designed and assembled with little or no thought to resonance control. Actually, I want you to think "resonance redistribution" when I write "resonance control." You don’t necessarily want to kill all resonances by embedding the entire product in asphalt or pouring the box full of visco-elastic polymer with a resonant frequency lower than 3Hz. Brute-force deadening of all resonances with heavy absorbent or damping materials is usually worse-sounding than effective resonance redistribution -- at least when we are dealing with electrical/electronic components. The one exception to this seems to be the power transformer. The more effectively isolated from the component’s chassis it is, the better the component seems to sound.
<<

 

[SY]

What do you mean "kill" the sound? What "disastrous" results: dielectric breaking or smeared output?

The usual confusion between sound and "sound." From an electrical standpoint, there's not much there.

There are bazillions of fine sounding amps out there made with transistors and ICs potted in epoxy, which analog deems "disastrous." That alone should give you pause and help you look at advice with an appropriate degree of skepticism.

If you can't induce microphonics in a piece of gear by tapping with a pen in various places, you've got nothing to worry about; the "resonances" will have no effect on electrical behavior. The downside is merely sociological. Mechanical percussion is a much stronger excitation than any impinging acoustic wave.

 

[Peter Daniel]

If you can't induce microphonics in a piece of gear by tapping with a pen in various places, you've got nothing to worry about; the "resonances" will have no effect on electrical behavior. The downside is merely sociological. Mechanical percussion is a much stronger excitation than any impinging acoustic wave.

I can't help it, but I also have to take a pause and look at your advice with an appropriate degree of skepticism.

What exactly is your experience in that area that you feel fit to give that sort of advice?

 

[SY]

What exactly is your experience in that area that you feel fit to give that sort of advice?

Are you looking for a CV? If so, I'd rather provide that to you via email.

Having built a few hundred amps on a DIY basis, (solid state, tube and hybrid), run dozens of controlled listening tests, a couple of decades of professional involvement with sensory testing, receiving more patents than I can count, and putting a few tens (maybe hundreds by now) of millions of electronic products out in the marketplace, I feel that my cautions might have some small basis in experience. This is not to say that I'm any kind of authority (I'm not an EE, my training is in physics and chemistry), or that I can't be proved wrong (that happens on a daily basis), but rather that my cautions to use some skepticism and common sense ought to be taken slightly seriously.