Solid state Pultec EQP1A power supply...

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the output B+ of the gyraf pultec is given by the ac output of the second transformer, and the voltage drop of the 3k3 2W,increase the ac value to have more than 325v, around 350v rectified and calculate with ohm's law tne value of the drop resistor to get 325 with the current needed, be carefull to take right voltage caps and right diode or bridge rectifier voltage
 
9 to 220 or 2x110 is fine too, and easier to find
that's real the 2nd transformer will overheat a little beat, but i'll do that in the G9 to get more HV, 220-15v--->12v-220v as it's write inthe G9 meta thread, and i've got no problem
Jakob is a pragmatic man, and he found a lot of good tips, thanks Jakob :guinness:
 
just put the rectifiers in there, fire it up for a few seconds so the caps don,t blow, recoed the B+, if it's under the cap rating, let it go like that.
You will only gain more headroom and less noise with the higher B+.

The engineers would have loved to get the voltage higher, but they were told that the transformer has to be cheap!
(less sec turns) so db wise, the went for bottom dollar.

use the octal socket/plug connecotrs, available at Allied.
8 and 11 pin, for stereo/crosstalk.
 
[quote author="drpat"]I'm taking on the daunting task of shrinking a 3space EQP-1A clone into a single rack space. My question is actually a two part question...

1. I want to forego the tube supply for a solid state supply. This will require a 325V feed and 6.3V to the heaters. Has anybody built a supply of this sort that has some insight or a simple way to go about this?

2. I want to make the power supply external for noise and real estate purposes. I know that this is done for tube mics all the time, I'm just looking for insight on adequate connectors and cable to carry the 325V to the EQ.

I've looked at the METAs, and the GYRAF Pultec power supply is the closest thing I've found, but the voltages are much lower that the requirements that a Pultec needs. Any help will be appreciated, and harsh truths are especially appreciated...[/quote]

Manley makes several one rack space pultec style eq's that are one rack space, with the power supply included. Perhaps you can go there for inspiration??

I don't know if it's solid state or not....
 
[quote author="drpat"]Yes, I've used them, and was very UNinspired...

Besides the Manleys, there are a lot of other one rack space EQs out there that don't sound like Pultecs, but decided to put the name on there anyways. I think some of them (Manley "Pultecs") are even transformerless :? That's like building a transformerless Neve, and slapping the slogan "Neve style EQ" on the front panel! Pure marketing BS to lure the idiots to buy something that says "Pultec" on it. I would guess that the majority of people who bought these things have never heard a Pultec, so what they don't know, won't hurt them, right?

What does all this ranting have to do with anything here? I don't know, I'll shut up now...

Do you have a schematic :green:[/quote]

The first 100 were made w/o a transformer. The later ones have a three way switch on the back. Two of the positions are phase flip and the other one is xformer bypass.

I don't, let me see if I can get one.


btw, I like them! :green:
 
I'll trade you a brand new HS 29 for that beat up 217!!!
Please! Pretty frikin please!
I will resign Papa Roach to your studio, Beverly Hills is doing them in.
:green:
 
the only transformer not in my closet is the 217 D.
Thats all I am interested in. Kayaking, and the 217 D.
Nothing else matters.

I paid Andy 250 bones for that HS 29.
I took one apart even. The thread is around here somewhere.
cj
 
sowter actually sounded better, but don't tell anybody.
i dont want this 29 to de preciate.
something about a little more twinkle on the high end.
 
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