The Amp Garage

The schematic you have is AFAIK the only one available for 5F6-A. Photos of vintage amps show that in production the tone stack used a 100k slope resistor (in place of 56k), and 100n bass cap (in place of 20n), and that the PI tail resistor was 6k8 (not 10k). Is this right for the evolution of the ...

what kind of amp is this?

Oddvar R wrote: ↑Fri Oct 27, 2023 10:44 pm So, that seems to be very good advices. Any suggestions on what transformer that could be?

which one did you not like? see if you can either add series resistance or find a transformer with lower voltage and/or more sag (less regulation and less current ability)

my experience with a weber twin PT was that it got hot and sagged a lot with 230v/50hz. the next transformer sagged way less, something that gave more power and punch. but you do loose some breakup, compression and mids. Perhaps that was what Oddvar was after here?

At mouser you get free shipping on the Hammond transformer. that's even better! (if you want the hammond and not some of the other PTs offered by TT) I have tried the TT ones,bought a lot from them. I returned the Dumble ones I bought, with a lot of hazzles I must say. They didn't sound as goog as ...

Tube Town lists the same Hammond 290EEX as I linked at Mouser EU above at nearly the same price. Don't know about shipping cost. yes, and they offer some other transformers too and the shipping and delivery times are not bad at all. At mouser you get free shipping on the Hammond transformer. that's...

martin manning wrote: ↑Mon Oct 23, 2023 11:21 am Tube Town lists the same Hammond 290EEX as I linked at Mouser EU above at nearly the same price. Don't know about shipping cost.

yes, and they offer some other transformers too and the shipping and delivery times are not bad at all.

Oddvar R wrote: ↑Sun Oct 22, 2023 3:24 pm

Great info there, maybe not so strange Weber doesn't answer. What transformer would you suggest?

try tube-town, for great value 50hz transformers

Oddvar R wrote: ↑Fri Oct 20, 2023 10:40 pm

martin manning wrote: ↑Fri Oct 20, 2023 11:40 am I don't see any mention on Weber's site that this transformer can be used with 50 Hz power. It only mentions "US voltages Power Transformer," which implies 60 Hz.

This is the INT version, made for 240v

the problem is not 240v but 50hz AC

martin manning wrote: ↑Fri Oct 20, 2023 11:40 am I don't see any mention on Weber's site that this transformer can be used with 50 Hz power. It only mentions "US voltages Power Transformer," which implies 60 Hz.

they have been seeling some export transformers but it is exactly these export transformers that often overheat with 50hz AC power

I have bought three Weber W022798 power transformers to put in a Dumble 50w ods. The amp itself sounds great, and the transformers works great for a awhile, the it starts blowing fuses. I have tried to search for every possible reason, but the 100w bulb limiter lighst up even when all the secondari...

it is well known that many weber transformers overheat with 50hz

known as hot shield, not safe really but may sound good

neskor wrote: ↑Fri Oct 13, 2023 8:34 pm I have one right know.
Impedance is around 6.5K

on the 15 ohms output arrangement, not the 7/8 ohms out?

Out of sheer idle curiosity, what are the opinions regarding the idea of building an Express with a choke? Because I realized, I have a choke lying around doing nothing at the moment. Pros and cons of adding a choke to the circuit? it kills the tone and response, if you replace the 1k resistor with...