Styroflex caps in a pultec

GroupDIY Audio Forum

Help Support GroupDIY Audio Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

jeroddumas

Well-known member
Joined
Jun 19, 2004
Messages
264
Location
georgia, USA
Can styroflex caps be used as filter caps in a gyraf pultec peq1? I have all values of the filter caps needed, but a couple or styroflex. Can they be used?
 
I'd seen mastering pultecs from manley with Styroflex inside and many other audio equipment...
They have small tolerances and the grid dimension is more variable instead of wima foil caps. :wink: I bought more than 10.000 of them (ebay). :wink:

Will work very good in the passive filtersection of the peq1.

Frank.
 
[quote author="nrgrecording"]I'd seen mastering pultecs from manley with Styroflex inside and many other audio equipment...
They have small tolerances and the grid dimension is more variable instead of wima foil caps. :wink: I bought more than 10.000 of them (ebay). :wink:

Will work very good in the passive filtersection of the peq1.

Frank.[/quote]

hi frank,
sounds interesting-so for a stereo pultec i could use styros instead of matched wimas?

thanx digichild
 
You can get both types in just about any tolerance you may want. But the styroflex'es are generally rated as some of the best types for precision works..

Jakob E.
 
Most WIMAs are available in either 5 % or 20% tolerances. Unfortunately most local dealers carry only 20 % ones. Some better online shops such as Reichelt in Germany (www.reichelt.de) offer both
 
[quote author="Rossi"]Most WIMAs are available in either 5 % or 20% tolerances. Unfortunately most local dealers carry only 20 % ones. Some better online shops such as Reichelt in Germany (www.reichelt.de) offer both[/quote]

that`s right...but i thought for a stereo pultec the tolerances should be below 5 %...and still i don`t know how i should choose the potentiometers...
 
...and still i don`t know how i should choose the potentiometers...

What do you mean exactly? How to get potentiometers with less tolerances?
What about stereo potentiometers or stepped attenuators?

Take a look at the manley pultec :wink: (pic from ebay)

manley_pultec_inside02.jpg
 
[quote author="nrgrecording"]
...and still i don`t know how i should choose the potentiometers...

What do you mean exactly? How to get potentiometers with less tolerances?
What about stereo potentiometers or stepped attenuators?

Take a look at the manley pultec :wink: (pic from ebay)

manley_pultec_inside02.jpg
[/quote]


stereo pots have tolerances of 10% or more-ne?

stepped attenuators are a cool idea,on the manleys the boost/cut has about 10 steps only?
not so much for 18 or something db...
 
stereo pots have tolerances of 10% or more-ne?

stepped attenuators are a cool idea,on the manleys the boost/cut has about 10 steps only?
not so much for 18 or something db...

I don't know... maybe 12 steps or so!? (lorlin 1x12) (at the mastering version from 1992)

But these enhanced manley pultecs have pots for boost/atten :

manley_102.jpg
 
so on the master eq they use switches also for boost/atten.?

and if you build a double mono eq for mastering(calreq eq) then the use of potentiometers seems to me funny (tolerance +/- 20%) when using caps and resistors of 1 % :?: :?: :?:
 
[quote author="jensenmann"]How about matching your components? DIY!!!!!
Get your LCR meter out and go for it, you lazy.....
:grin:
cheers
Jens[/quote]

thanks for your advice-so what you think:how much have the potentiometers to match?also 1 or 2% ?

by the way its not my lazyness that i ask stupid questions here all the time but rather my unexperience :wink:
 
That depends on what the potentiometer does, and what tolerances you'll need on what parameters.

For stereo EQ's, the important spec IMHO is to get the frequencies tracking accurately - specially if you run high Q's. The lift/cut and Q-regulation are much less chritical - just keep them tracking within 0.25-0.5 dB, and you're good.

The pots in the pultec are for lift/cut and Q regulation, and are thus not very chritical to match accurately.

Jakob E.
 
[quote author="gyraf"]For stereo EQ's, the important spec IMHO is to get the frequencies tracking accurately - specially if you run high Q's. The lift/cut and Q-regulation are much less chritical - just keep them tracking within 0.25-0.5 dB, and you're good.

Jakob E.[/quote]

can you please tell me how should i do that?
 
Back
Top