Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Kcz5o on November 20, 2020, 08:33:12 am

Title: Transformer question
Post by: Kcz5o on November 20, 2020, 08:33:12 am

Can anyone tell me if I can substitute a power transformer that is rated at 700cvt@200mA for the primary with a power transformer for one that is 690cvt@150mA for the primary? All other windings are the same. I am running 2 EL34s and 3 12ax7s with a Gz34 rectifier? I am trying to put together an amp but don't know as much about transformers as I should.

Title: Re: Transformer question
Post by: Latole on November 20, 2020, 08:50:24 am

Yes.

50 watts Marshall amp use these specs

https://www.tubesandmore.com/products/transformer-marshall-replacement-power-50-w

Title: Re: Transformer question
Post by: Kcz5o on November 20, 2020, 08:54:28 am

thank you very much!

Title: Re: Transformer question
Post by: pdf64 on November 20, 2020, 09:23:12 am

It is worth noting that a typical Marshall EL34 pair with 3k4 OT draws far more than 150mA from the PT’s HT winding.