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The Black Amp


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#1 bpribadi

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Posted 27 September 2004 - 08:29 AM

Black in color Black in sound headphone.gif

Based on PPA 1.0 circuit diagram, with OPA637 and one BUF634 per channel.

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The Front Side
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The Back Side
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The Board without the Panasonic FC Capacitors
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The Tracks
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The Inside
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Panasonic FC
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The Blue ALPS * The Modded Neutrik Socket * The Buffer With Heatsink
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My Fav Blue LED
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headphone.gif Bram headphone.gif

Edited with ImageShack Links... PhotoBucket down no.gif

Edited by bpribadi, 27 September 2004 - 03:36 PM.


#2 digi01

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Posted 27 September 2004 - 10:13 AM

WELL DONE!BRAM headphone.gif
the ground channel is a 634 only?
diy

#3 huangyong

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Posted 27 September 2004 - 10:25 AM



VERY NICE AMP.....
GIVE IT A " 5 STAR" AWARD laugh.gif

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#4 bpribadi

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Posted 27 September 2004 - 10:34 AM

Thanks guys! happy.gif

Yes Digi, one BUF634 for the ground channel. I think any headphone (except AKG K1000, they are ear speaker anyway, not headphone) will not need more than 100mA per channel, so the 250mA from the BUF634 should be sufficient.

Did you guys had any problem with the pictures? I heard photobucket has network problem no.gif

Edited by bpribadi, 27 September 2004 - 10:34 AM.


#5 Q00

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Posted 27 September 2004 - 11:23 AM

Wow! Really neat eventhough u had very tight spacing! Great job! w00t.gif
A job like this can only mean that u had a lot of pre-planning done.
My question though is what does it run on? Batteries or dc supply?
And the all important question...how does it sound? tongue.gif

Well done and cheers mate.

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#6 bpribadi

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Posted 27 September 2004 - 11:28 AM

QUOTE
Wow! Really neat eventhough u had very tight spacing! Great job! 
A job like this can only mean that u had a lot of pre-planning done.
My question though is what does it run on? Batteries or dc supply?
And the all important question...how does it sound?


Thanks!

You are right, the planning took more time than the actual assembling job wink.gif

I set the voltage at + & - 7.2 volts regulated. Means, can use normal 15 volts adapter which normally gives output at around 18 volts (unregulated), or 2x 9volts battery.

It sounds very good to my ears, my brother like it also. I will cover more of how it sounds later. So far had been burnt in for around 7 hours.

#7 bpribadi

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Posted 27 September 2004 - 02:25 PM

If anybody got problem with the pictures from photobucket, here is the link to the pictures in imageshack:

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#8 heady

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Posted 27 September 2004 - 05:11 PM

Bram, AWESOME. I have been working on a pimeta, at first I tried to do what you did but it was hard to get the wire to stay flat when soldering it and I gave up and use another type of perf board. You clamped the wire down while soldering? I really like the case, where did you get it?

Wow, hope I have a chance to audition it before you sent it to your brother. happy.gif

Man, you are good.
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#9 Absolute0

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Posted 27 September 2004 - 05:16 PM

The neatest (both figuratively and literally) work I have seen! wub.gif

Those are mini inputs and outputs if I am not mistaken. They look really cool against the black enclosure.

Btw, did you get the PPA board from tangent? Isn't there a newer version?
Period.

#10 bpribadi

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Posted 27 September 2004 - 05:22 PM

Thanks Heady!

I use visegrip to grip the cooper wire flat. The cooper wire will expand when heated, so sometime make it difficult to put them nicely. Vicegrip helps a lot. You can borrow it from me, I'm not using it at the moment.

The casing is Hammond 1455N1201, I bought it from Farnell-Newark. They are Newark item, so they charge it in USD, it cost me SGD 41.- (w/ GST). I feel it is so expensive, but my brother likes it.

I also hope that I can try it longer, but my brother brought it to Jkt already huh.gif , so I only tested it for a while. But the so far the OPA637 sounds very good with RS-1. My brother will connect it with Sony XA7 CDP and Grado RS-1, and he will share his impression. Waiting for it happy.gif

Anyway, it doesn't sound much different than my Pimeta, for the OPA637 being very neutral with the right level of treble, and the AD8066 feels a tad more 'airy' with a tad brighter treble.

#11 bpribadi

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Posted 27 September 2004 - 05:25 PM

QUOTE
Btw, did you get the PPA board from tangent? Isn't there a newer version?


Thanks Absolute0!

I didn't buy the PPA board. The newest so far is version 1.1, the different is only in the jfet cascode class a biasing of the op-amp. The version 1 is fixed to 1 mA, the 1.1 is adjustable.

Beside that the power supply also different. But here I'm using my own circuit for the power supply, using LM2941 regulator.

Edited by bpribadi, 27 September 2004 - 05:26 PM.


#12 heady

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Posted 27 September 2004 - 06:09 PM

Bram, I was hunting for a nice casing for my second pimeta (ambitious ah, not finish first one which I am trying to fit into sweet tin) in SLT but found only low quality and frankly ugly ones only. Wow the cost of the Hammond is "ouch"!! Our hobby is expensive. wacko.gif
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as he sigh for the love of a lady"

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#13 huangyong

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Posted 27 September 2004 - 06:51 PM

nice board as well.. where you got it..
what i got from SLS are always those cheapo boards... really lousy stuff

#14 [email protected]

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Posted 27 September 2004 - 06:55 PM

Well done!

QUOTE
...
And the all important question...how does it sound? 
...


The other important question is how much will you charge to have one built? wink.gif

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#15 bpribadi

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Posted 27 September 2004 - 09:38 PM

QUOTE
nice board as well.. where you got it..


I bought it in Indonesia about 8 years ago biggrin.gif It is some left over from my University project wink.gif I think it is gold plated, because of the durability, still very clean and shiny, no stain at all after 8 years in storage. Normal copper will not last that well. I think I saw similar board in SLT, forget where...

QUOTE
The other important question is how much will you charge to have one built?


All are estimated price in S$:
110 for 2x OPA637 & 3x BUF634
40 for Hammond box
20 for the blue ALPS
10 for the Neutrik socket (haven't include the S$2.5 fake neutrik that I bought to mod the spring)

With other stuff like the resistors, Panasonic FCs, connectors, mini sockets, switch, cable, etc. It cost around S$250.- parts only. But it matches amps with price 3x or more it's price wink.gif So still worth tongue.gif