Yamaha PM-1000 direct outs with EA-2623 xfmrs?

Quick backstory.  A friend/client in my area operates a popular recording studio, and we've been discussing numerous details for a new "B room" in the building.  This space will be mainly used for demo recordings and perhaps rehearsal space, but also will have links to the "A" room via line and mic level tielines in/out of patchbays.  Future plans may include additional recording/mixing rooms as well.

The "B" room will have a Yamaha PM-1000-16 desk, and  the various recording possibilities requires me to add direct outs from the input modules.  One solution is clear to me, and that is to use a 1:1 output transformer for each of the 16 modules' outputs in order to ensure galvanic isolation to whatever may end up on the lines throughout the building.  (We can all argue about using THAT balancing chips, impedance balancing, etc. in a different thread.)

The last stage in a PM-1000 input module is fairly beefy, with the same circuitry (except for size of the output coupling cap) used for the group outs which drive 1:1 Tamaura (IIRC) iron.  Hence, plenty of moxie to drive 1:1 iron from Edcor (at the low end of the price spectrum) through Cinemag in the middle up through Jensen at the top end of pricing. 

While pondering, I recalled the Ed Anderson iron sold by Jeff at Classic API.  It appears to me that an EA-2623 with both secondaries wired in parallel could be an excellent "in the middle pricing" choice.

Comments?

Bri

I've used the tamura 1:1 on PM-1000 modules, taking the out put from right before the pan pot I believe.  The out put is a little on the low side, certainly usable but it surprised me.  You might want to consider a transformer that has a 1:2 option.

I think that's an interesting choice, Brian, and would likely sound wonderful.  I'm actually in the process of doing the same thing for friend's 16-channel PM1K for as well, though using Edcor WSM600:600.

If you did want a little more level in hand you could also try those wired 1:2.  Try both and go with whichever sounds better.

BTW, I'm altering the EQ on my buddy's board.  The frequencies (1k, 2k, and 4k) and narrow Q of the mid band makes it pretty unusable to me, and the high band is a little too harsh for my taste.  I've left the LF alone (sounds nice already) and made the three choices of mid band 350Hz, 1k2, and 5k, with a wider Q and raised the HF to 12k instead of the stock 10k.  Much more applicable to all kinds of things, including sweetening duties, which the stock EQ just could never do.

JC

Hi JC,

Care to share about what to change to adjust the Q on the PM1K? I have about 8 channels here that I'm going to put into a little sidecar mixer. I remember at one point I changed the low mid band cap to a 2.2uF Wima polyester, which I believe would put it around the frequency you ended up with? Can't remember, but I think that's all I did so far (it's been awhile)

Do you change the "Q" by altering resistors? Which ones, and I'd be curious to know what you ended up with.

Jon

P.S. Brian, don't know if you're still looking at this thread, but have you tried the Ed Anderson transformers yet?

There's also the Carnhill CA-18-VTB2290, 2:1 or Carnhill CA-18-VTB2281 1:1 which might be cool.
I've tried the Cinemag CMOQ-2S in the PM1000 outs and thought it was very nice, big and smooth.

I just have a bunch of the Tamura now so I'll probably use those, but maybe I'll make a couple tricked out channels with the Carhills or something. . . . I don't know.

JW said:

Brian, don't know if you're still looking at this thread, but have you tried the Ed Anderson transformers yet?

There's also the Carnhill CA-18-VTB2290, 2:1 or Carnhill CA-18-VTB2281 1:1 which might be cool.
I've tried the Cinemag CMOQ-2S in the PM1000 outs and thought it was very nice, big and smooth.

I just have a bunch of the Tamura now so I'll probably use those, but maybe I'll make a couple tricked out channels with the Carhills or something. . . . I don't know.

Click to expand...

The transformer mentioned in the topic IS an Ed Anderson design:

http://classicapi.com/catalog/product_info.php?cPath=21_37&products_id=86

I always assumed the "EA" in the part number was there to recognize Ed's design <g>.

Bri

edited