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Help finding data on vintage Peerless Transformers
Old 4 weeks ago
  #1
Here for the gear
 

Help finding data on vintage Peerless Transformers

Hello,

i got a set of 2 x input and 2 x output transformers that i pulled from a working Westrex cinema PA tube amp ( it was impossible to keep it and restore it... ).

They seem to be Peerless / Altec Lansing corp. Transformers, with references : T-101, T-102.

i already looked in the Peerless catalogs of 1960, 1953 and 1950 that are on the net, the references doesn't match, but at least they fit the "Q" type enclosure

If anyone has infos or know who to call / e-mail, where to post ?

Thanks !
Attached Thumbnails
Help finding data on vintage Peerless Transformers-1.jpg   Help finding data on vintage Peerless Transformers-2.jpg   Help finding data on vintage Peerless Transformers-3.jpg   Help finding data on vintage Peerless Transformers-out-1.jpg   Help finding data on vintage Peerless Transformers-out-2.jpg  

Help finding data on vintage Peerless Transformers-out-3.jpg  

Last edited by Flavien Plus 8; 4 weeks ago at 07:46 AM.. Reason: spelling
Old 4 weeks ago
  #2
Quote:
Originally Posted by Flavien Plus 8 View Post
Hello,

i got a set of 2 x input and 2 x output transformers that i pulled from a working Westrex cinema PA tube amp ( it was impossible to keep it and restore it... ).

They seem to be Peerless / Altec Lansing corp. Transformers, with references : T-101, T-102.

i already looked in the Peerless catalogs of 1960, 1953 and 1950 that are on the net, the references doesn't match, but at least they fit the "Q" type enclosure

If anyone has infos or know who to call / e-mail, where to post ?

Thanks !
This might be a good place to start https://www.diyaudio.com/

or https://www.vivatubes.com/viva-news-...formers-added/

or https://audiokarma.org/forums/index....former.874751/

Hope this helps
Old 4 weeks ago
  #3
Here for the gear
 

Hello !

Thanks !

I didn't know about Vivatubes
Old 4 weeks ago
  #4
This website has a PDF of Altec Transformer Specs. https://www.telephonecollectors.info/

Also http://www.lansingheritage.org/html/.../altec-cat.htm

This site has Peerless tranformer catalogs from the early 1950s https://www.technicalaudio.com/pdf/P...s_Transformer/

Hope this helps!
Old 4 weeks ago
  #5
Lives for gear
 

Peerless transformers

Quote:
Originally Posted by Flavien Plus 8 View Post
i got a set of 2 x input and 2 x output transformers that i pulled from a working Westrex cinema PA tube amp
are you in the UK ?
Westrex cinema power amplifiers were not all that popular in North America, but had a significant presence in Britain with both electronics and loudspeaker systems.
Quote:
Originally Posted by Flavien Plus 8 View Post
Peerless / Altec Lansing corp. Transformers, with references : T-101, T-102.
those are Westrex references.
4452 is the Peerless input transformer indentifier, most likely a custom part not found in catalogs.
Quote:
Originally Posted by Flavien Plus 8 View Post
If anyone has infos or know who to call / e-mail, where to post ?
looking at your photos, the input transformer is likely a step-up, 600 ohms, split primary windings with taps, to push-pull grids. very possibly a 1:10 ratio.
the output appears to be for coupling push-pull plates with center tap, to low impedance loudspeaker coils: maybe 0, 4, 8, and 16 ohms.
a seasoned technician can measure the resistance of the coils and determine turns ratios of each.
in any case, Peerless transformers are considered by many to be superb.

Mike of MagneQuest "owns" Peerless but not sure if still in business.
http://magnequest.blogspot.com/p/about-magnequest.html
Old 4 weeks ago
  #6
Here for the gear
 

thanks !!

in the 3 catalogs i looked at ( 1960 / 1953 / 1950 ), there is no corresponding ref in the input / output section.

i reviewed all schematics at : https://www.westernelectric.com/arch...ier-specs.html

the westrex A10 amp and A11 amps have T120 ( input ) and T121 ( output ) refs.
all transformers have refs number upper than 120, even designs that where created in the 30's...
the original amp looked a lot like their model 100 and 101, but half smaller and less "structure" ( more point to point wired )
I would guess around 50W power.

EDIT : in the transformer general info pdf, there is a 113 output transformer for westrex 9A amps listed.
and the ret-ardation coils T101 used in A8A and A8B amps.



Tubes where stolen during storage, so i only retrieve 2 6sj7 and 1 6K6gt tubes.
NB : Amps also has "transformer alike" "ret-tard coils"( curse lang. corrector hide this ), and mini oil tanks capacitor
still got them, can post photos if someone is interested.

@ cathode : i'm in france ! ( Lyon ), the amp was in cinema in Nancy.


The transformers are currently at a friend's who is a tube amp tech.

Here is a quick set of measurements which match with your guesses guys
Attached Thumbnails
Help finding data on vintage Peerless Transformers-img_20200426_103652.jpg  

Last edited by Flavien Plus 8; 4 weeks ago at 08:33 AM.. Reason: curse lang. editor doing inapropriate correction
Old 4 weeks ago
  #7
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So i guess i have enough info to move on,
and consider different option to use them in a stereo transformer "mojo box".

i'll look around, to see if i can go passive

but i'll also looked at this class A transformer driver card :

"Dual Class-A II Output" (DCAO2)
https://ka-electronics.com/shop/inde...&product_id=67

or maybe finding a class A tube circuit that can use both sets of transformers
( in & out ) to make a little unity gain ( or close ) amp
Old 4 weeks ago
  #8
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in case, i attach the 3 peerless catalog that are on the net here
Attached Files
File Type: pdf Peerless_50cat.pdf (6.99 MB, 1 views) File Type: pdf Peerless_53cat.pdf (5.30 MB, 1 views) File Type: pdf Peerless_60sCat.pdf (3.41 MB, 1 views) File Type: pdf transformer westrex 01-general-information.pdf (15.03 MB, 3 views)
Old 4 weeks ago
  #9
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Westrex cinema amplifiers

Quote:
Originally Posted by Flavien Plus 8 View Post
Tubes where stolen during storage, so i only retrieve 2 6sj7 and 1 6K6gt tubes.
observations and notes.

your Westrex amps appear to be US made, post WWII but pre 1958 Litton acquisition (Triad transformers).
tubes mentioned are octal base: 6K6gt is a modest power output tube.
6SJ7gt could be the input pentode; possible the tubes stolen were for the phase inversion.

quick usage of the input transformers: direct boxes.
wire the high impedance side in series, the low impedance side in parallel.
you will then have a di with very low input loading and very high vibe.

otherwise, build a pair of super quality balanced tube microphone preamps,
similar in design to McCurdy AU-300 or Langevin 5116b.

good application of the Peerless output transformers depends largely on the turns ratio.
based on the apparent physical size, a line level device seems appropriate rather than a hi-fi inspired monitor amplifier.
Old 4 weeks ago
  #10
Here for the gear
 

@ cathode : Thanks !

in my limited experience with vintage gear, i always liked more Class A / single ended design.
I didn't know about those pre, the Langevin 5116b looks like a nice project with these transformers ( if specs match closely enought), i'll talk about it with my tube tech friend.

i was trying to sell him to some class A push pull design, but those i found are not documented enought...


i remembered i also saved the control panels, and... tadaaa !

the amplifier was a Westrex A2 amp !

as you can see, the is a montoring section ( pot ) and a power section ( huge attenuator ), i remember there was a least 10 tubes in it...

EDIT : i asked Mike of MagneQuest via his facebook page about them.
EDIT : i asked a australian cinema vintage gear seller about it as a Westrex A2 is ( or was ) in his listings
i'll post any additional info here
Attached Thumbnails
Help finding data on vintage Peerless Transformers-screenshot-2020-04-28-12.56.12.jpg  

Last edited by Flavien Plus 8; 4 weeks ago at 01:23 PM.. Reason: additional infos
Old 4 weeks ago
  #11
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Westrex A2

well, that front panel certainly looks British, as does the large rotary switch,
thus retracting my assumption the assembly was American made.

this Russian site has photos of the A2 setup, one can see the Peerless transformers and what appears to be a Tech Labs input attenuator.

https://www.soundup.ru/index.php?opt...fiers&Itemid=7

also liking class A circuits.
though the Peerless input transformer with split secondaries is ideally suited for a balanced tube mic pre such as the 5116b, no reason it can't be applied to a single ended circuit such as the RCA BA-11a.
Old 4 weeks ago
  #12
Here for the gear
 

Thanks again !!

Please, correct me if i am wrong ( tube design is such another planet for me ... ),
but the push pull output transformers can't be used in a single ended design as they don't have a gap and can't handle DC right ?

so if i want to use the whole set, i'm tied to finding a push pull circuit ?

( i see the choke "trick" ( ? ) on the RCA OP6, but i'm no designer so i'd rather stick to a design that fit close to the transformers i have )




PS : Should i open another thread now ?
Old 4 weeks ago
  #13
Lives for gear
 

Westrex A2

Quote:
Originally Posted by Flavien Plus 8 View Post
Please, correct me if i am wrong ( tube design is such another planet for me ... ),
but the push pull output transformers can't be used in a single ended design as they don't have a gap and can't handle DC right ?

so if i want to use the whole set, i'm tied to finding a push pull circuit ?

( i see the choke "trick" ( ? ) on the RCA OP6, but i'm no designer so i'd rather stick to a design that fit close to the transformers i have )
the push-pull output transformer can be used n a single ended design by the parallel feed method, aka "parafeed". yes, the OP-6 approach.
https://www.sowter.co.uk/Parafeed-transformers.php

it will be less costly to go all balanced if you want to use the whole set.
Old 3 weeks ago
  #14
Here for the gear
 

Quote:
Originally Posted by cathode View Post
well, that front panel certainly looks British, as does the large rotary switch,
thus retracting my assumption the assembly was American made.

this Russian site has photos of the A2 setup, one can see the Peerless transformers and what appears to be a Tech Labs input attenuator.

https://www.soundup.ru/index.php?opt...fiers&Itemid=7

also liking class A circuits.
though the Peerless input transformer with split secondaries is ideally suited for a balanced tube mic pre such as the 5116b, no reason it can't be applied to a single ended circuit such as the RCA BA-11a.

Hello!
I'm the guy trying to build something with the transformers
I'm trying to replicate a langevin 5116b

The prototype's working but bass response is not that great (see REW mesurements)

I'm not sure the input transformer in wired correctly though... That could explain the bass response ? How would you wire the dual primaries and secondaries ?
As for the output transformer, i'm a guitar amp guy, i'm used to a 8 ohms load that will blow the output transformer il you don't hook it up... I'm a bit lost with here. What i did is mesure the impedance and calculate the turn ratio of the OT and tried to mimick the 20k:600 the amp is calling for. The best i can do is get 40k:600.
Then the output is hokked straight into my sound card for mesurements ....
Attached Thumbnails
Help finding data on vintage Peerless Transformers-mesure3.jpg  

Last edited by pi_amp; 3 weeks ago at 07:44 PM.. Reason: wrong cutnpaste
Old 3 weeks ago
  #15
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Langevin 5116b/ Westrex A2

Quote:
Originally Posted by pi_amp View Post
I'm not sure the input transformer in wired correctly though... That could explain the bass response ? How would you wire the dual primaries and secondaries ?
Then the output is hooked straight into my sound card for measurements
1. there may be an issue with your sound card's output capability feeding the relatively low input impedance of the T101.
but lets do what we can.
wire T101 for maximum inductance.
i.e., go in to terminals 3 and 6,
strap 5 and 4 together which becomes the center tap and connect as shown in the 5116b drawing.

2. unclear what the output transformer taps are actually designed for.
line level amplifiers such the 5116b are best terminated, but will generally not toast the transformer is left floating,
there is little danger as in hi-fi or guitar power amplifiers.
so for the time being, until you find the proper termination/tap, derive your output from terminals 4 and 5.

3. while your graph demonstrates some low frequency deficiency,
the top end looks stellar. good work !
Old 3 weeks ago
  #16
Here for the gear
 

Quote:
Originally Posted by cathode View Post
1. there may be an issue with your sound card's output capability feeding the relatively low input impedance of the T101.
but lets do what we can.
wire T101 for maximum inductance.
i.e., go in to terminals 3 and 6,
strap 5 and 4 together which becomes the center tap and connect as shown in the 5116b drawing.

2. unclear what the output transformer taps are actually designed for.
line level amplifiers such the 5116b are best terminated, but will generally not toast the transformer is left floating,
there is little danger as in hi-fi or guitar power amplifiers.
so for the time being, until you find the proper termination/tap, derive your output from terminals 4 and 5.

3. while your graph demonstrates some low frequency deficiency,
the top end looks stellar. good work !

1. Ok for the primaries of input transformer T101
but for the secondaries ? 7 and 8 ? 9 and 10 ? Thanks !!!
Old 3 weeks ago
  #17
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Westrex A2

Quote:
Originally Posted by pi_amp View Post
1. Ok for the primaries of input transformer T101
but for the secondaries ? 7 and 8 ? 9 and 10 ? Thanks !!!
input transformer secondaries:
7 and 10 to respective input tube grids.
strap 8 and 9 which becomes the center tap, connect as in 5116b.

apologies for previous comment about primary transformer connections 4 and 5,
they become a center tap, can be used to apply phantom,
but generally not connected to anything else.
Old 3 weeks ago
  #18
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@ cathode => thanks !!

Mike from Magnequest responded... all his stuff is in storage as he retired.
Old 3 weeks ago
  #19
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Quote:
Originally Posted by cathode View Post
input transformer secondaries:
7 and 10 to respective input tube grids.
strap 8 and 9 which becomes the center tap, connect as in 5116b.

apologies for previous comment about primary transformer connections 4 and 5,
they become a center tap, can be used to apply phantom,
but generally not connected to anything else.
Thanks!
got rid of the ground problem by connecting one side of the line out to ground (it was floating)
i'm starting a new thread for that langevin build
Topic:
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