Bassman 5F6-A Build

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Super_Reverb
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Bassman 5F6-A Build

Post by Super_Reverb »

Am thinking about a Bassman build and wondering if there are any words of wisdom or experience to share?

thanks,

rob
Last edited by Super_Reverb on Fri Jun 29, 2012 6:06 pm, edited 1 time in total.
Teleguy61
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Re: Bassman 5F6-A Build

Post by Teleguy61 »

The 5F6-A is the Mother of All Amps that we know.
Use good parts, take your time, and rock your brains out!
tubeswell
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Re: Bassman 5F6-A Build

Post by tubeswell »

^good choice of words^
He who dies with the most tubes... wins
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martin manning
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Re: Bassman 5F6-A Build

Post by martin manning »

One thing to note is that the values for the slope resistor and bass cap, and the PI tail shown on the old (1956) Fender schematic (56k, 0.02u, and 10k) are different from those used in production units. The 1990 reissue schematic reflects that, and shows them at 100k, 0.1u, and 6k8.
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Phil_S
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Re: Bassman 5F6-A Build

Post by Phil_S »

One of its primary offspring is the Marshall JTM-45. Look at that schematic, too. IMO, its hard to go wrong with one of these.
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The New Steve H
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Re: Bassman 5F6-A Build

Post by The New Steve H »

Don't use a crappy tube at V1. I don't like Electro Harmonix 12AX7s, but I stuck one of their 12AY7s in there, and it's great. For the remaining preamp tubes, you might consider Tube Amp Doctor. They're not real expensive, and they sound good.

I got a nice sweet sound with Svetlana 6L6s. I tried Winged Cs, and I thought they sounded shrill and thin.

Also, you might consider installing PPIMV. I did. Hasn't hurt anything, and it makes the amp somewhat more versatile.

Make sure you get a chassis that actually fits the components. I built a JTM45 for a friend, and the Mojo chassis he bought was a real headache.
Relax. It's SUPPOSED to smoke a little.
Teleguy61
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Re: Bassman 5F6-A Build

Post by Teleguy61 »

http://stores.ebay.com/Yen-Audio

I've had good luck with this seller for new tubes.
Reasonable prices, fast ship.
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The New Steve H
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Re: Bassman 5F6-A Build

Post by The New Steve H »

One more vote for Yen Audio. Good service.
Relax. It's SUPPOSED to smoke a little.
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Super_Reverb
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Re: Bassman 5F6-A Build

Post by Super_Reverb »

Thanks for the good info. I was considering (cheating) using a 12ax7 and a split load plate resistor (to simulate lower transconductance 12ay7) for 1st preamp stage. I have some NOS RCA 6L6s and tung sol (re-issue) 5881s for the outputs.


rob
Teleguy61
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Re: Bassman 5F6-A Build

Post by Teleguy61 »

You can try a few preamp configurations to see what you like best.
The basic sound of the amp is in the cathode follower tone controls and the phase inverter.
5881s will sound good in it, but it will love the NOS RCAs.
They like to be played loud. MVs and PPIMVs work and are useful, but it's not really what the amp's about.
You're just trying to contain the beast.
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