Ever heard of a PECLA ?

[leigh]

I was reading an article from Resolution magazine about the design of some old school eqs/comps, and they talk about a PECLA 1VV. Google's got nothing on this... anyone?

The article:
http://www.resolutionmag.com/pdfs/TECHNO~1/techcraftsig.pdf

The description:
"PECLA 1VV ? This must be the original recording
channel, but unfortunately is of unknown origin. The
signal first passes through the compressor section,
being very similar in design to the Altec 436.
The PECLA offers additional front-end gain to the
Altec, together with an extra control for selection
of compression ratio. The signal then enters the EQ
stage. The circuitry would suggest that the EQ stage
is of Pultec program equaliser design. I received
this unit as a gift in non-working order. I have since
brought it back to life and all I can say is, whatever its
origin, it sounds very good."

Ooooh, ancient audio secrets!

Leigh

 

[pucho812]

you know the deal. lets see some schemos,inseide pics, etc,etc,etc

 

[leigh]

[quote author="pucho812"]you know the deal. lets see some schemos,inseide pics, etc,etc,etc[/quote]

Eh? I just read about this, you'll have to buttonhole the author of the article for more details...

Leigh

 

[pucho812]

. I received
this unit as a gift in non-working order. I have since
brought it back to life and all I can say is, whatever its
origin, it sounds very good."

I thought you wrote that as opposed to quoted that... my bad no worries

 

[basilhenriques]

Made by Philips Holland for the BBC..
The PECLA, (Pronounced PEEK -Lah) Peak Effect Compressor Limiter Amplifier.. early 1950's... in those days the boffins filed it under RSA's (Response Selection Amplifier) all BBC nominative colloquialisms, no longer in use but still remembered by some of us.
The references to Altec 436 compressor section and Pultec program equaliser design, are wrong because the Pecla pre-dates them buy half a decade or more.. two models, one was Phillips, a light green case and the other was Pye (light blue) built by Phillips broadcast and was later in the 50's/60's.

 

[pvision]

I'd expect PECLA to be Program Equaliser Compressor Limiter Amplifier or even Program Equaliser Channel Limiter Amplifier

Peak Effect is redundant if it's a limiter but, or course, the BBC Department of Redundancy Department may have had something to do with it

Nick Froome

 

[ruffrecords]

Although you say it pre-dates the Pultec EQP1A, it is about as identical to it as you can get judging by the front panel controls. So who nicked whose design?

Cheers

Ian

 

[gyraf]

Nicking-question is important - but box does not look early-50, neither does meter. Or text for that sake. Philips head screws in aluminum chassis...

..pic is from saturn-sound http://www.saturn-sound.com/images%20-%20outboard%20&%20all%20tape%20units/pecla-1vv%20-%20valve%20compressor%20and%20eq%20unit.jpg

..smells a bit like fabrication/forgery/falsification of history..

Jakob E.

 

[ruffrecords]

I have emailed him to ask for further info on it.

Cheers

Ian

 

[HugoM]

I've got two of them. Apparently from Marquee studios. Here's a shot of the back.

 

[HugoM]

They worked very well in the 80's. Pulled them out of storage, the signal goes through but they're both rather weak.

 

[alphasnk]

That's super cool, thanks for the photos Hugo, and welcome

 

[HugoM]

Thanks Alpha! I'm trying to get them running again. (They were brilliant in the early 80's).
On the inside, they are a mixture of a Pultec EQP-1A and a UA 176! The grid voltage seems very low,270 v. Valves are 6AL5, 6CG7, 6BC8 ECC83 and an OB2 voltage regulator. Gardner mic transformer, 2 potted transformers either side of the passive EQ, and an output transformer.
If anybody out there has a schematic, please get in touch, as I#m going mad trying to decipher the EQ section!

 

[pucho812]

Thanks Alpha! I'm trying to get them running again. (They were brilliant in the early 80's).
On the inside, they are a mixture of a Pultec EQP-1A and a UA 176! The grid voltage seems very low,270 v. Valves are 6AL5, 6CG7, 6BC8 ECC83 and an OB2 voltage regulator. Gardner mic transformer, 2 potted transformers either side of the passive EQ, and an output transformer.
If anybody out there has a schematic, please get in touch, as I#m going mad trying to decipher the EQ section!

Weak signal, check caps and tubes

 

[HugoM]

Thanks Pucho.
I have 2 of them. Swapping the tubes makes no difference, and apart from changing the big electrolytics, the 50 caps in the eq section would take for ever. The mains transformer has primary tappings at 205, 225 and 245 volts. Currently set on 245 in a country where the mains voltage is around 230v. Maybe I should change it to 225.

 

[HugoM]

And of course, the colour is battleship grey!