BF Bassman OT swap for more options?

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marqueemoon
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Re: BF Bassman OT swap for more options?

Post by marqueemoon » Fri Sep 30, 2022 3:33 pm

johnnysomersett wrote:
Fri Sep 30, 2022 12:05 pm
marqueemoon wrote:
Fri Sep 30, 2022 9:24 am
I thought this is part of what the pedal/pedalboard power amp was intended to address. :whistle:
Actually, I wanted to come back and elaborate on this. The Pedal/poweramp situation was to address the times I might have to get to a gig on public transport*. Most of the time the three of us travel up in a car (with limited space) together...on these occasions the ability to use any cab laying around that's part of the evenings kitshare/house equipment is a massive benefit as I can just leave my cab at home and just sling my guitar, pedals and amp head in the car and off we trot.

*although, at the moment the Ballsmom is mostly getting use as a bass preamp at home :D
Glad to hear you’re still digging the pedal.

Yeah, good to have options.

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øøøøøøø
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Re: BF Bassman OT swap for more options?

Post by øøøøøøø » Sat Oct 01, 2022 10:48 am

I will state the obvious:

Much of the amp’s sound is in the output transformer.

It may not be a *drastic* difference using the Hammond OT as opposed to the vintage Schumacher original, but that also might depend on your definition of “drastic”

Definitely save the original part!

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JSett
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Re: BF Bassman OT swap for more options?

Post by JSett » Sat Oct 01, 2022 11:02 am

øøøøøøø wrote:
Sat Oct 01, 2022 10:48 am
For sure Brad... I've used the Hammond transformers a few times and they've always sounded great/accurate to my ears.

And I keep everything from vintage gear that I swap out. Well, apart from the odd bit here and there that I know I'll never need (like the PT from my VibroChamp that I gave to Justin for his Tweed Princeton build) and old filter caps.
Silly Rabbit, don't you know scooped mids are for kids?

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Re: BF Bassman OT swap for more options?

Post by Sauerkraut » Mon Oct 03, 2022 1:57 am

johnnysomersett wrote:
Thu Sep 29, 2022 10:22 pm
I was thinking the other day about my BF Bassman head and the fact that I'm slightly restricted with the options of only 4 or 8 ohm cabs. Often I'm gigging at places with kitshare going on and, here in the UK, a lot of them are setup at 16ohm.
I'm in a similar spot with my 35 watt, 4 ohm Tremolux head. I think swapping the OT is a good way to go, but instead I left mine in and went with having more than one cab. Depending on what kind of show I'm playing and the size of the van we're renting, I'll either bring my 2x12" or my 1x10" (both 4 ohm). The small cab weighs next to nothing and takes little space. As my 7 watt home amp also runs at 4 ohm, I can combine both amps and cabs whichever way I like. One downside is that I don't get to compare loads of different cab and speaker configurations. But I know that it'll at least sound good and I won't start some futile quest for the "ultimate" speaker, or worse... be tempted into building a 4x12" cab.

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Re: BF Bassman OT swap for more options?

Post by JSett » Tue Oct 18, 2022 10:30 am

Finally got around to sorting this tonight. The Hammond was a direct drop-in which is always nice but the impedance selector needed the Ext Speaker hole reaming out about half a millimetre...not the end of the world but I prefer not to take a drill to a chassis where possible. Oh well.

The wiring was pretty simple really but, note to anyone reading this now, or in the future, who's considering doing this... The Hammond blue and brown wires on the primary DO NOT match the blue and brown on the output tubes. I got a rather wonderful full-volume blast of oscillation thanks to it having positive feedback. Definitely woke me and the cats up from our relaxed state :D :D a quick swapover sorted that out and al is well

Image

Image

Image

Photos are before the wire swap.
Silly Rabbit, don't you know scooped mids are for kids?

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