[Megaptera]

Quote:

Originally Posted by petery83 ... was thinking about using the PPA as a preamp for my studio monitors, but still haven't gotten the necessary adapters to do so...

In case you don't know: The PPA's design means you can't use the headphone out as a preamp out like you can with a lot of other headamps. If it wasn't built with a seperate preamp out, it will need some minor modifications. (I use mine as a preamp myself.)

 

[PinchyCM]

chalk up another for another PPA. i love mine.

i'll get around to putting some shiny new buffers in it someday.

 

[Akku]

I still listen to my PPA (my first DIY) and modding it. Recently installed AD744 with bypassed output and even with intersil buffers is a clear improvement.
It's a great project and has a lot of options and "add-ons" to settle with an amp that fits your preferences. I finished an M3 yesterday and I like it but I have not decided yet who's the best for me. Time will tell but I doubt I will ever sell the PPA.

 

[petery83]

That's a bummer...So that means using my PPA as a volume control without modifications is a no-go?

What are those modifications by the way?

Quote:

Originally Posted by Megaptera In case you don't know: The PPA's design means you can't use the headphone out as a preamp out like you can with a lot of other headamps. If it wasn't built with a seperate preamp out, it will need some minor modifications. (I use mine as a preamp myself.)

 

[bg4533]

Quote:

Originally Posted by petery83 That's a bummer...So that means using my PPA as a volume control without modifications is a no-go? What are those modifications by the way?

Preamp output from the PPA should use the output signal with input ground. This is pretty easy to do if you can solder. My PPA has an extra set of RCAs in the back and a switch to go between headphone and preamp.

I don't know what will happen if you try using the headphone out for preamp purposes.

 

[Megaptera]

Basically the PPA, and a few other popular DIY amps, has a third channel as ground -- this provides some really nice technical benefits, but it means that there's a difference between the input signal ground and the output of the ground channel's circuitry. If you were to short these together, which is what would happen indirectly with a lot of source/power amp combos, you'd wind up with an unstable amp.

To get around this and have your PPA usable as a preamp, it needs a seperate preamp-out (with a switch to select which output, of course), connected to the left and right outputs from the board, and grounded to the board's input ground -- or even the input jack's ground. It's not terribly difficult to do, but if you're not comfortable Doing It Yourself, I'd suggest asking the original builder to do it.

For more details on the output ground channel, check the DIY forum -- I'd rather not go into too much detail here, just to keep things on topic. But it is definitely possible, just so people know.

 

[ppl]

Quote:

Originally Posted by Akku I still listen to my PPA (my first DIY) and modding it. Recently installed AD744 with bypassed output and even with intersil buffers is a clear improvement. It's a great project and has a lot of options and "add-ons" to settle with an amp that fits your preferences. I finished an M3 yesterday and I like it but I have not decided yet who's the best for me. Time will tell but I doubt I will ever sell the PPA.

Yes Indeed the AD744 comp pin mod is real smooth i use it myself in my PPA V2 with aos DAC and yes i still enjoy it verry much