Pre-amp for chip amp

[Nuuk]

Lesson ?

Sorry, I meant to say sermon!

 

[!]

I don't think that anybody said that we did!

I was only answering Sinski who had asked why we can't have a simple kit version of the AD815.

The UNO pre-amp design, kindly supplied by Carlos, has some gain, is reasonably simple, and is more than adequately documented on Decibel Dungeon. What more do you want?

I used your site search but found no "uno". Is it based around an opamp like OPA627 with or w/o BUF634?

Edit: Oops, I found it, no comment yet.

What I want is no opamp, and especially no integrated buffer chip. No capacitor in signal path. Topology not *audiophile* parts should be the key here... but I am not a preamp wizard so I keep looking...

Ok now comment on the UNO-

Many of us already have ~ 4.7uF cap in the input of the GC. So too we see it in the UNO. The ideal is (IMO) an adjustable pre (gain not even as important) without DC offset, no cap on the GC input or buffer (pre) output. No caps in signal path at all, zero, zilch, none, anywhere. I may build the UNO anyway though, but too many other things piling up to get to it immediately.

 

[!]

Yes, i woluld like to have best possible design with best possible sound. It can be simple, or complex, but it has to be relativ easy to build and what i am missing is just a ready ps pcb and pre pcb for one simple or complex gc buffer.

I have build already few complex circuits in the past, but always with ready pcb.

Something like "Premium gc buffer" kit with best possible components similar to premium kit pro Peter Daniel is just not existing yet.

So, finally:
I am just missing a good quality pcb for gc buffer and i am wondering again, that they are so many people looking for gc buffer, but there is no ready pcb to buy.

Cheers, sinski

I'm looking for the ideal topology, schematic. If it's appealing enough I'll just etch the board myself same as I did with the GC PSU & amp board to keep it consistent. Pre-made boards are nice but inevitably the designer gets stuck on their own ideals too much and doesn't allow for parts substitutions or even some minor topology changes.

I'm not as interested in a premium buffer kit, that just reads like an overpriced endeavor, waste of $ because... One of my goals is no capacitors in signal path and there are no high current needs, the whole thing should cost about $10, or $20 counting the PSU since it should only need some transistors, resistors, diodes, etc. I suppose you could go way up in cost with special resistors and diodes but if the design is valid it should work well with common grade parts as well as exotics. That's just an ideal though, obviously if someone were motivated enough to put the project together and do a kit they should get $ for their time too if they want it that way. It starts departing from DIY though, if *everything* is done for you except soldering the peg into the hole.

 

[Nuuk]

Many of us already have ~ 4.7uF cap in the input of the GC. So too we see it in the UNO.

If you have a cap on the input of the amp, you don't need another on the output of the pre-amp (or visa versa).

There probably isn't anybody building hi-fi who wouldn't like to keep all caps out of the signal path. But anybody who has built/designed enough knows that this game is full of compromises! I'm not saying that it isn't possible but it almost certainly won't be simple!

It starts departing from DIY though, if *everything* is done for you except soldering the peg into the hole.

I agree. And what do you learn?