Altec transformers

[Quayhog]

Assuming I wire my preamp input and outputs to agree with tha altec schematic such as the 1567c will any of the Altec branded transformer octal modules work without damage? 

Will other branded Octal transformers such as Dukane, McGohan work in a socket that conforms to the Altec Schematic.

Which bridging transformers should I seek out, one that takes a 15k primary and converts to 600 ohms? 

I find the subject somewhat confusing and I'm looking fo a less expensive alternative than the 4722.

Thanks for your responses
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[gato]

I'm not sure that I understand the question, but if you're asking whether all octal Altec transformers are interchangeable then the answer is no. Also beware because there are transistor amps that come in that same package.

 

[Quayhog]

Thanks for the response.  I was asking for socket wiring  compatibility, I guess there is no conventional way shared by Altec and by Dukane and others.

The solid state units I'm aware of.  All my transformerless mixers are tubed.  I do have a Berlant MCM-2 mixer that I will resocket with nine pins and use a set of Bogen Transformers.

I seem to have collected a few transformerless mixers I'd like to make useable and I'm trying to locate originals or some that are atleast electrically compatible.

 

[gato]

Here's the pinout for the Berlant Line Input Transformer.
I'll try to find some others as well.

 

[gato]

Oh also,
These may be useful: https://tubedepot.com/products/8-pin-octal-tube-base-only

 

[sahib]

.......
I seem to have collected a few transformerless mixers I'd like to make useable and I'm trying to locate originals or some that are atleast electrically compatible.

I have a good collection of Altec octal transformer and micpre modules if you are looking for additional modules. Please PM if interested.

 

[Quayhog]

Another related question.  I have three Altec 342B mixer amps.  How do you bridge the amps together.?  These amps do not have a 600 ohm output.  I have some bridging trannies and a few others.  Right now I have all the transformer slots filled with 4722.    It's taken years to collect these without paying huge amounts of money.
Ultimately what I want is three preamps with one amp loaded with 7027 power tubes and speakers.

 

[gridcurrent]

I have three Altec 342B mixer amps.  How do you bridge the amps together ?  These amps do not have a 600 ohm output.  I have some bridging trannies and a few others.  Ultimately what I want is three preamps with one amp loaded with 7027 power tubes and speakers.

Refer to the schematic, note the "auxiliary input".  It is isolated from the mixing bus by 470k (R40).  Shorting out R40 will allow direct access to the summing bus with your similarly modified 342b amplifiers.  Test and verify as the added cable capacitance may be of concern, a grid stopper resistor might be prudent.
The 342b does not have a 600 ohm output but does have a 150 ohm output tap for 70 volt systems.  70 volts is +39 dBu,  just a bit  more than what is needed for your a2d.  Even the 16 ohm tap is capable of over +29 dBu.  I would suggest the 16 ohm tap which is also the point from which  feedback is taken.
Referring to your earlier post regarding Altec transformers:  the 15095 is a logical choice for a lower gain input, but some re-wiring is in order.  As specified on the 15095a, strap 1 to 4, and 3 to 6.  The secondary winding terminals for both the 4722 and 15095(a) are 7 and 8.  If you want to reconfigure the inputs for bridging, radical rewiring is required.  Note that input positions 3 and 4 have an extra connection utilising pin 1, a connection to the top of their respective level controls.