Do it yourself projects Pultec EQ

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<rbmrocket@aol.com> wrote:
>guitar.
>>After successfully building a pair of LA-2 clones at about $600-650
>apiece, I thought perhaps its time to build a pair of Pultec EQP-1A's.
>>Does anyone know about how much this would cost?
>>Does anyone one have a build it from scratch manual for sale like the
>Johansen manual for the LA-2?
>>I've downloaded the schematics for the Pultec and the tubetech (really
>a great clone) and not in my price range.

Basically, does it have to sound like a Pultec, or does it just have to
sound good?

It's easy to build a Pultec clone that sounds good... there isn't much to
a passive EQ network. Even the DIY EQ project I did in Recording a year
ago isn't THAT far off the Pultec design, and you can easily copy the
Pultec with off-the-shelf inductors. I think Sowter is even making
reasonable clone inductors.

BUT, making it so that the inductors swing the same way the Pultecs do,
and give you the same weird low end effects that the Pultecs have, that is
difficult. None of the Pultec clones I have tried really work like Pultecs,
although pretty much all of them are useful.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

Archived from groups: rec.audio.pro (More info?)

<rbmrocket@aol.com> wrote:
>Scott,
>>does the Manley "enhanced" pultec come close to a pultec?

Not even a little bit.

>>Is the tubetech ...c1 a pultec clone?

I don't know, I have never taken one apart.

>>People describe enhanced possibly because the old transformers are no
>longer available and they >are using newer parts that require an
>alteration in the original pultec and they feel it is >better. I
>personally have no transformer wire wrapping experience. I believe the
>original pultecs >had hand wound transformers. I would indeed like to
>make an exact copy if possible.

You can't. The original output transformers are not available. The
original inductors are not available.

Personally, I don't like the bass compression thing that the Pultec does,
but plenty of people do. Enough to make the Pultec, which used to be the
cheap equalizer that you got if you couldn't afford anything good like
a Cinema Engineering filter bank, into an outrageously expensive surplus
piece.

After all the >LA2's I made are EXACT
>COPIES with the UTC HA 100 transformers, carbon resistors and NOS
>>potentiometers.

Sure, but those are all comparatively easy to get. I'm not sure why
you'd want to do this (carbon resistors.... I've spent too much time
finding drifting ones), but for the most part you can get most vintage
parts other than magnetics.

>>I just purchased on Ebay the schematics CD for the Pultec. I figure,
>if I can find the parts, or >for that matter , if I had the schematic
>for the tubetech. it could be made for perhaps $250 a >piece. That's a
>better savings.

You do know that the Pultec manuals don't have the schematics for the EQ
networks in them, right?

You could probably get the manual for the Tubetech if you asked them for
it, but I'm not sure you'd really want to clone it.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

Archived from groups: rec.audio.pro (More info?)

<calcerise@hotmail.com> wrote:
>You'd think someone would have revese engineered the Pultec filter
>block by now, although it has to be said, the Scott is right-the Pultec
>was and still ought to be the mid-market, rather than high end,
>solution.

Sure, lots of people have reverse-engineered the filter block... I'm just
saying that if he's paying money for the manual, he is going to be
disappointed.

The filter module itself really isn't anything special, to be honest.
Which is part of why so many people out there are making Pultec-esqe
equalizers.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."