This is not just another gainclone

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Finally, Jean-Paul, where I come from, calling another person's statements "nonsense" is considered pretty rude. But hey, this is the internet, what should one expect?

It depends what the definition of rude is. Where I come from we might think different about this. We consider negative comments that miss the subject rude.I don't recall you being one of the most civilized here with your posts either.
BTW I still think your post about the Peter Daniel Gainclone lacks any understanding of this thread. It is NOT about looks, it is about quality of sound. Peter showed us the amp and the short signal path, the vibration damping chassis of which he says it contributes to the good results. If you know other pics of Peter's amps you would know he never makes ugly unfinished devices.In other words: he made it so rigid for the soundquality and he would do the same with a tubeamp or a Aleph whatever. So the finishing of the case does not draw our eyes away from the fact it is only an IC amp. It is and will be. He could have mounted in a brick of stone for the same reasons and maybe sound would have been as good.

A useless discussion so it seems. If one wants to think negative it will be a negative experience.

There are more threads about this subject and the amp has been compared with commercial gear. The comparison with high end IS ridiculous but people have done it and the IC amp didn't drown.
Please reread Peter's posts comparing it with the Aleph 5 and X :whacko:

I have experience with IC amps, but I have not built this particular clone ( yet ). But I will build one as the parts arrive and maybe I will comment on the quality here. To me that is a better way than being negative without knowing. Or being rude as we say it.
 
dave

"""That they offer such potential with such simplicity* & with such a low financial investment is the beauty. Hopefully we will start to see more systems with many amplifiers and no passive XOs"""

dave, exactly!!!!!!

btw, one of my biggest mistakes was that i bought my atc scm 100sl as the passiv version - stupid stupid stupid!!!:smash: :smash: :smash: :smash: :smash:
 
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Joined 2002
As far as comparing it to a class A, award-winning design that is such a crock I can't even begin to describe. It's actually offensive.

Grataku, please explain this one. What is wrong comparing them with eachother especially if one knows the outcome is that the IC amp sounds better ?

Audiogear is about sound, regardless of price, looks etc. etc.
If a 10 $ transistorradio sounds better than a 1000 $ tubeamp I would choose the transistorradio wouldn't you. ( slightly exagerated example, I know ).
We once compared a 500 $ DIY DAC with an Audio Note DAC 3 ( 5000 $ or so ? ) and were not really able to distinguish A from B. After hours of serious listening we decided that both were equal.

Offensive don't you think ?
 
Disabled Account
Joined 2002
OK, Mark but what means "they are not in the same league" ?

If the IC amp sounds better it plays in a higher league, does he mean that ?

I think he means these expensive class A power eating monsters that cost mucho $ and have patents on them MUST sound better because of price and design. Well, as we could read it does not matter as much as we want to believe. ;)
 
Hi,

MRehorst said:
This thread is interesting. A bunch of people are getting excited about an IC amplifier when under normal circumstances, these things would not be given any respect whatsoever. Why? because Peter Daniel's does a really nice (and I mean REALLY NICE) job of packaging the things. Could it be that people are more impressed with packaging than content? Could that be the reason why so many "high-end" pieces of equipment appear to have far more $ in the metal work than in the circuits? Could it be that an amp is an amp is an amp?

It's one of those things that make me go "hmmmmmmm...".

MR

A long, long time ago...
I can still remember how
That music used to make me smile.
And I knew if I had my chance,
That I could make those people dance,
And maybe they'd be happy for a while.

Hell, a long, long time ago... When Yuppies where Yuppies and the Great Wall of Berin stood firm against the evil imperialist agressors I build Amplifiers with Chips. And Discrete. And Valves.

And while I appreciated even then the differences in Sound, a TDA2030 did not neccesarily sound any worse than a good discrete Amplifier. If you use the wrong layout and parts you can make ANY amplifier sound crappy, if you know what you are doing you can make any competently engineered circuit sound at least decent.

Compared to the LM3875 the old TDA2030 I played with nearly 20 Years ago is crude in comparison, so why should a minimalitic Amp based on the LM3875 with the right circuit, layout and parts NOT sound great?

Because life is not meant to be that easy? Well, SOMETIMES it is.

Sayonara

PS, time for someone to try a mixture of current and voltage feedback to give an easily set output impedance or even pure current drive to the Speakers Voicecoil (I did that stuff too ages ago).
 
A few years ago when repairing a Sony amplifier, I ran it up and noted an interestingly and unusually good sound.
Closer inspection under the covers revealled the source was LM3875 IC power amplifiers, and on the bench that day had a clearness that was/is not to be had from standard Sony and other discrete, or Driver IC/Discrete output transistor amplifiers.
I believe Peter and others who do contend that this is a good amplifier within its limitations are well correct.
Intelligently powered, constructed, loaded and driven, it really ought to be a clean, zippy and precise little amp, relatively easy to construct, and real cheap to boot.

I find that modern IC power amps are mostly pretty good, and whilst layout is somewhat important, it can be surprising how bad a layout most of these IC's will tolerate and still sound fairly good.
The biggest gains are to be had by choosing good quality components, mostly supply and coupling capacitors, and solid central earth reference and earthing.
I agree with Dave that these ought to be a really good way of building multi-way active loudspeakers, and economically, an application just going begging to be done.
If correct impedence compensation is applied across the individual drivers, a really cooking 2/3 way 'plate amp' would surely result that would not break most banks.
(A little thought just popped up - Is it better to adjust individual amplifier input levels or amplifier gains to adjust for differing driver sensitivities ? - either scheme could be easily implemented in an active speaker).
Most modern shelf systems rely on IC power amplifiers, and generally do not sound too bad to a helluva lot of people - with better layout and parts, these would satisfy most of us for normal domestic situations.
Just because it is IC, does not mean that it is bad.

Eric.
 
I build a quadriamped horn system with active crossover and gainclones on the upper three ways. I posted the pictures earlier in this thread.
The same speaker set up was fired in an house friend with his triode single ended amp and passive crossover, their were really well builded Set with Tango Opt and nos valve.
The sound with the two set up was different and being both very good I and some others preferred the the gainclones for ritmic transparency and immediacy but still very relaxed and undirstoted sound probably thanks to the multiamp.
The valve sound a bit less focused and maybe sweeter on the top end.
You can compare different amp and different class in the end is the music you want not the electronics.
If you prefer one or the other is just a matter of taste but the gainclones are not just cheap amp they play music.
Giorgio
 
protos said:
I think the datasheet shows a differential input for the chip. Does that mean it can have a balanced input?

It certainly can be balanced. Look at this Marchand Electronics application:

http://www.marchandelec.com/ftp/pm21man.pdf

Problem is you will also need a proper balanced signal to input into it.

BTW: this balanced capacity also allows an easy bridging, as the manual suggests.


Carlos
 
Has anybody tried the Burr-Brown/TI series of power opamps (i.e. OPA541, OPA548, OPA549)? This is a very interesting thread. I'm surprised that nobody has mentioned these or the LM1875... In my opinion the LM1875 is the better sounding chip... I am also partial to the OPA548 even though it's a lot more sensitive to power supply noise. It's very musical and seems to provide a little bit more detail than the rest.

Just my two cents...
 
Kuei Yang Wang said:
Hi,



PS, time for someone to try a mixture of current and voltage feedback to give an easily set output impedance or even pure current drive to the Speakers Voicecoil (I did that stuff too ages ago).

I'm actually doing that now. 18"elf woofer, 2*18" dipole, Goodmans Axiom 80 in a conical front horn, piezo supertweeter per side, modded Electro Voice 4 way digital crossover with 20 bit non-os DACs - and everything driven separately with chip amps in pure current mode.
I was not a big fan of the Gainclone sound compared to 300Bs. But current drive is something different. The 300B sold since then.
 
analog_sa,

the reason why i asked to eleborate was that i just finished a set of lm3886 based amplifier, which i decided to 'help' with a dc-servo :D. These amps will be powering my biamped speakers for a little while, until my discrete ones are finished.
I have not fired them up yet, but perhaps I should compare the gainclone versus the one with the servo... The gainclone should not take hours to solder.
 
"Rod Elliot writes a cutting but probably true critique of 47 Labs and their bogus and flakey engineering claims."

Rod was also concerned by the very large profits made, and the poor quality control of the Gaincards. He adds that after his experiments IC based opamps "sound very good indeed" - something I have found too (I have used the LM3886 and 3876 in separate projects).

Check out the article here:

http://sound.westhost.com/madashell8.htm#gaincard
 
My version

Ok peoples: I haven't read the entire thread (skipped through parts), but will show you my recently finished gainclone:

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An externally hosted image should be here but it was not working when we last tested it.

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At first, I had significant hum, but after a rewiring with my help from my dad, I now have almost none. And my speakers are 98 db efficient, so I think that's very good now.
 
As to the question of whether the Gaincard is a ripoff: if you look at Elliot's numbers, it's really not all that bad.

Consider the Bottlehead Foreplay, heralded as an audio "bargain" - it may be about $25 in parts but try going out and sourcing all those parts yourself.... cutting the plate, having step-by-step instructions, etc etc. So it can be said that for $150 this preamp kit is still a good value. Then consider that if someone packaged it to look decent (and given the sound quality) it would probably sell for upwards of $1k. Maybe way upwards. It's all relative.

Development cost, labor, marketing, these all have to count for something. Oh yeah, and profit. There are a lot of ripoffs in high end audio but Kimura's creations are not the first place to look. IMO. (though they are too expensive for me)

May I add, when my stepdad had a problem with his Flatfish, Sakura sent him a new one immediately by express delivery - he had it within 2 days - before he'd even returned the faulty one. That's pretty good service.

Noam

p.s. and fwiw, the three reviewers who put the Gaincard on the map (Reichert, Dudley, Rochlin), none of them are exactly sycophants of the High End either...
 
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