Fender transformer substitute

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Ondrej
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Fender transformer substitute

Post by Ondrej » Tue Dec 10, 2019 3:25 am

Being in a rush for my 5f8a project, I have mistakingly bought the iron from Classic Tone:

OT: 40-18102 - http://www.classictone.net/40-18102.html
Choke: 40-18003 - http://www.classictone.net/40-18003.html
PT: 40-18042 - http://www.classictone.net/40-18042.html

I just realized, they are not 5f8a specs - rather they fit the Twin Reverb family.

I guess they will work (a quad of 6L6's), but the question is what will be the tonal impact?
Before soldering them, should I just use them or sell them and get the correct iron?

Any oppinions?
THanks

danman
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Re: Fender transformer substitute

Post by danman » Tue Dec 10, 2019 5:21 pm

As long as the voltage rating and current specs on the PT are close to the 5f8 spec, there should not be any problem. Make sure that the OT has the correct primary impedance and that the secondary winding taps will match your intended speaker load.

The bigger issue is whether the bolt pattern is the same so that they will fit in the chassis that you intend to use.

Ondrej
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Joined: Sat Oct 08, 2011 1:33 am
Just the numbers in order: 7
Location: Czech Rep.

Re: Fender transformer substitute

Post by Ondrej » Thu Dec 12, 2019 5:18 am

The bolts fit fine (for the OT, I did have to drill extra holes, but all seems to fit fine).

What my concern is that I don't know how much tonal difference there is going to be - mainly with the different OT. For the PT, I know I would have to go to solid state and I bare all the tonal consequences. The bigger issue is the OT, since the original 5f8a was apparently much larger.

danman
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Re: Fender transformer substitute

Post by danman » Thu Dec 12, 2019 5:50 pm

A smaller OT will compress and saturate sooner than the larger unit so the amp may overdrive a bit sooner. It will likely have a little less low end also. I would think that the core tone of the amp will remain the same though.

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