Amp Camp Amp - ACA

That's what I thought but I noticed this reference by waam68 in an earlier post. I have read just about everything but that post caught my eye.

Hi Bcmbob.....Don't pay to much notice of me as I only just know what I'm doing! ;) Anyhow the ACA with pc power supplies is still doing great as my main amp so worth giving it a go stock before experimenting. If it gels with your speakers this amp punches above its weight with great bass and lots of detail. For info mine is dead quiet with no turn on thump and my stock sinks only get warm rather than hot. I did email nelson pass who kindly replied saying there was plenty of scope to up the supply voltage in the power supply so at some point I will give that a go.
Regards
Mike
 

6L6

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Use one of Peter Daniel's 'universal' power supply boards as a single rail. You will need a 14-15v transformer, diodes for the bridge, some big capacitors, say 30,000uf or so at 25+ volts and a handful of .47ohm 3W resistors. And all the associated widgets for the mains side of the transformer. (power plug, fuse, line cap, switch...)

More info in this thread - http://www.diyaudio.com/forums/audio-sector/149672-universal-power-supply-pcb.html

The board would generally look like the stuffed side of this -
139304d1251302814-universal-power-supply-pcb-ps1.jpg


Peter Daniel can be contacted here - http://www.audiosector.com/contact.asp Or just shoot him a PM
 
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There is no downside in using the SMPS - it's what the ACA was designed for, after all... :) :) :)

But I ask, being a novice and all, is there an upside to using something other than the SMPS?

Or is it just a matter of choosing which one you want to go with that is cheap and handy (I have a surplus Hammond, a nicely made Meanwell SMPS, and power bricks from laptops galore).
 
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ACA

I have been listening to my amp camp amps for a week or two. Eventually I will finish my build of a F5v3. Several people have asked how the ACA sounds and will they drive their speakers. The simple answer is that Nelson Pass designed it. He said he wanted to see the smiles on some people's faces as a birthday present to himself. Yes, it sounds good! It is very detailed and yet sweet with extended highs and deep bass. I am very pleased and can enjoy sitting and listening to music for hours. My speakers are the ZRT kit from Madisound, which you can look up and see they are about 87 or 88db/watt. They are plenty loud for me in a medium small room. Only a few times does it show a limit of power. For example, in a Telarc recording of Copland's "Fanfare for Common Man", when the big bass drum hits, the sound just does not go any louder as it should, but it is a soft clip and that is getting louder than I usually want. I did not have means for metal work but a friend has a table saw. I put together some 1x2, 1x4 and some 1/4" hardwood plywood lying around...and some stain. I put each mono amp near its speaker with short speaker cable. IMG_0145.jpg Build it; you will probably be very pleased. Thank your very much, Nelson; I have a smile on my face!
 
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But here's the fun part: You can build a power supply and compare it to the SMPS and see what you think.. All the parts of the amp and power supplies are so cheap, why not? In fact why not build 2 pairs so you can compare them more easily! :p

There is no downside in using the SMPS - it's what the ACA was designed for, after all... :) :) :)
 
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Hi Bcmbob.....Don't pay to much notice of me as I only just know what I'm doing! ;) Anyhow the ACA with pc power supplies is still doing great as my main amp so worth giving it a go stock before experimenting. If it gels with your speakers this amp punches above its weight with great bass and lots of detail. For info mine is dead quiet with no turn on thump and my stock sinks only get warm rather than hot. I did email nelson pass who kindly replied saying there was plenty of scope to up the supply voltage in the power supply so at some point I will give that a go.
Regards
Mike

So you're using 12v supplies from a PC? or 19v from a PC laptop?
 
One 19v 3.5a supply into each channel driving a 15 ohm load. The sinks do get quite warm but not what I would call hot. Mind you I did build it skeletal style and its by a window in the coldest room in the house....woke up to snow on the ground this morning:hohoho: I do have an old spare30v 4.5a tx ...might see what that does!
Mike
 
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There is no downside in using the SMPS - it's what the ACA was designed for, after all... :) :) :)

The choice of a SMPS was crucial to the project, not because the SMPS is
superior, but because it is do-able safely in the hands of people who may
have just soldered for the first time.

I looked at the project and saw that the AC line voltage safety was the
elephant on the dance floor. At the same time Marlin P Jones had some
nice 19V supplies for $3.99, so (typical me) I bought a large quantity and
designed around them.

Are the SMPS better? I really haven't invested much time in the question -
they are what made this possible. I can tell you that if we had to construct
supplies at the workshop, at the end of the day only a few of the amps
would have been working. As it was, it was a bit of a struggle to see to
it that they all worked.

:cool:
 
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One 19v 3.5a supply into each channel driving a 15 ohm load. The sinks do get quite warm but not what I would call hot. Mind you I did build it skeletal style and its by a window in the coldest room in the house....woke up to snow on the ground this morning:hohoho: I do have an old spare30v 4.5a tx ...might see what that does!
Mike

OK, great, there was confusion about your "PC Power Supply" Some thought it was from a desktop PC and thus only 12v.
So now it's confirmed- Mike is using 19v like everyone else. Except for the guys trying higher power versions.. heck, I found some laptop power supplies online putting 26v! Not sure there's really a point , but when did that stop us!

The amps with SMPS supplies sound quite good as you've heard about. Is a linear supply better? possibly, does it sound better? I don't think we know.
 
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I do find no small irony that Nelson designed this amp to be a great performing, SIMPLE design, delivered same and yet folks just can't resist "messing" with the amp.

Seems to me that if you want more you ought to be building an F5 Turbo. ;)

But it isn't about wanting more, I think it is about what iterations with unique or novel characteristics people will create and have "pop" up to fit certain tastes based on the Amp Camp Amp.

Amp Camp Amp, Amp Camp AmpTurbo, Burning Amp Camp Amp, Amp Camp Amp EVUL, Amp Camp Amp-X, Amp Camp Amp 3/30/60/90/1000**, Mini Amp Camp Amp, and Amp Camp Amp Zen (Bride of, Son of, and plain old).

So long as the Amp Camp Amp stays affordable enough, uses laptop SMPS bricks, and is a good starting point for the novice audio DIY'er, then I am willing to try out a few of the iterations while keeping a stock Amp Camp Amp. It has piqued the interest of a lot of my friends and with these voltages and heat, it isn't something they no-longer fear or fret about.

** Amp Camp Amp 1000 -- as a kit this would include 50 SMPS... :D