Me so excited!!! Tube Mic Pre from PAiA!

  • Thread starter Thread starter jaykeMURD
  • Start date Start date
jaykeMURD

jaykeMURD

I sit on you.
Yep, decided it was time to:
1. Get another preamp
2. Get another preamp that's "better" than my good ol' DMP3

I've actually purchased 2 of PAiA's Tube Mic Pre Kits and an enclosure.

Besides some light-to-moderate electronics work and modification, this'll be my first REAL step into audio electronics.

Not to mention, I'm confident these pres will give me a signifigantly different sound than my DMP3 can. Maybe not really better, but heck, I bought ALL that's nessicary to complete a 2-channel TMP for a little more than a new DMP3 would run.

I llooooooove building things, and am becoming more keen on electronics and such. I plan on eventually moving up to more DIY projects, like the Gyraf-Designed G9 MicPre and SSL Comp.

I've also got a new solering iron/station on the way. A Hakko 936 ESD-Safe station. Pretty good jump up from my $20 soldering iron.

Anyone else have any experience with this TMP?

I plan on also performing all of the modifications for this TMP as shown here over at TapeOp. I'll probably modify one channel and keep the other stock and make some recordings and share them. From what I've been able to asess, the modifications make this pre quite useable!

Wish me luck!
 
I have a set of those. Yes, they will be better than a DMP3, probably even the unmodded version. FYI it is a lot easier to mod these from the start. Mine was already built unmodded and most of the work is removing the old parts and cleaning out the board to accept the new parts.

I modified one of them, and not the other (I have the parts, on the to-do list).

My findings of the modded pre are good and bad. I took extensive tests before and after I modded it.
The BurrBrown ICs are obviously a better choice, and you'd imagine running DC to the tube will be best as well.

The problem I found is more AC ripple in the output once I modded the pre. I found that also affected the output AC ripple of the unmodded pre too (they share the same power supply, but not power supply filtering).

I think by using that 1W 15ohm resistor to balance the load puts a load on the "wall-wart" mains transformer (that resistor get's nice and HOT). It has a hard time handling the new load. Therefore putting less filtered DC voltage, and more ripple to the power legs of the ICs. That would explain why the unmodded side suddenly has more ripple hum.

I plan on upgrading the transformer with one that can supply more current, or redesign the power section a bit so that it does not require that power hungry balancing resistor.

Also I read in a forum a post by the author of that article stating that the values of C21 & C22 should not be 10uf, they should stay as 33uf, or even bypass alltogether since the BurrBrowns have almost no DC offset. i checked myself and got no DC offset at all with them bypassed. Sorry I can't site that post, I have no clue what forum I saw it on.

Good luck and have fun.
 
Back
Top