5F6a importance of output configuration

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Baltar
Posts: 37
Joined: Mon Apr 14, 2008 10:36 am
Location: Austria

5F6a importance of output configuration

Post by Baltar »

Moved to Technical section
Baltar
Posts: 37
Joined: Mon Apr 14, 2008 10:36 am
Location: Austria

Re: 5F6a importance of output configuration

Post by Baltar »

looks like my post is gone, so once more..

Hi again,

i'd like to try a 5f6a bassman in 6v6 configuration.
i thought about lowering voltage by using a 5y3.
due to 6k6:2r trannies are rare i'd use a deluxe reverb-ot
i still have in stock, which would require to wire the
speakers in series/parallel config to 8r.

what do you think - is it worth a try, or would the
amount of sonical influencing changes(tubes, tranny,
speaker response) result in something, that sounds very
different to a bassman?

cheers, B
Jana
Posts: 1314
Joined: Sun Sep 07, 2008 10:40 pm
Location: Minnesota

Re: 5F6a importance of output configuration

Post by Jana »

I say go for it. If you can get the B+ to be around 350 to 380 or so, I think that will be a nice sounding amp. I think that would be a nice clubbing amp.
Baltar
Posts: 37
Joined: Mon Apr 14, 2008 10:36 am
Location: Austria

Re: 5F6a importance of output configuration

Post by Baltar »

thanks for you opinion.
i'm going to design the power supply-6l6-like and just alter
the rectifier, tubes, and ot. so in case i want to, the upgrade would
be easy.
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Structo
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Joined: Wed Oct 17, 2007 1:01 am
Location: Oregon

Re: 5F6a importance of output configuration

Post by Structo »

Sorry about that Baltar, I didn't realize I had deleted your text.

I'm still learning which buttons to push. :lol:
Tom

Don't let that smoke out!
Baltar
Posts: 37
Joined: Mon Apr 14, 2008 10:36 am
Location: Austria

Re: 5F6a importance of output configuration

Post by Baltar »

no worries :) thanks for moving
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renshen1957
Posts: 498
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Location: So-Cal

Re: 5F6a importance of output configuration

Post by renshen1957 »

Baltar wrote:looks like my post is gone, so once more..

Hi again,

i'd like to try a 5f6a bassman in 6v6 configuration.
i thought about lowering voltage by using a 5y3.
due to 6k6:2r trannies are rare i'd use a deluxe reverb-ot
i still have in stock, which would require to wire the
speakers in series/parallel config to 8r.

what do you think - is it worth a try, or would the
amount of sonical influencing changes(tubes, tranny,
speaker response) result in something, that sounds very
different to a bassman?

cheers, B
Hi,

Some would worry more about the the B+ voltage than the Output Transformer. Kelley used a higher B+ and a circa 4k2 ohm OT on his 4 6V6 FACS. I have run 6V6 tubes in Bassman Transformers. You can run 6V6 tubes at a lower OT primary, your distortion will be higher, but in a guitar amp distortion is good.

Some of the newer 6V6 tubes can handle higher voltage.

Some things to consider as to rectifier tubes:

How much mA current the tube can handle.

Check out http://www.300guitars.com/articles/rect ... drop-chart

Regards,

Steve
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rp
Posts: 2528
Joined: Sun Apr 25, 2010 4:21 am
Location: Italy

Re: 5F6a importance of output configuration

Post by rp »

Structo wrote:I'm still learning which buttons to push. :lol:
Tom, the wrong button could definitely be trouble! Here's a safety primer for you:

http://www.youtube.com/watch?v=6MMkiq8Kxis

Baltar, I'm thinking you want to keep the preamp voltages and PI close to 5F6A / JTM45 level for best sound, so you might have to play with the power string.
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tubeswell
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Joined: Thu Mar 27, 2008 6:42 am
Location: Wellington. NZ

Re: 5F6a importance of output configuration

Post by tubeswell »

Well you could also do a 5F6A with 4 x 6V6 and then you could use the same OT.

As far as the PT goes, 2 x 6V6 should work well with a 5Y3G or a 5R4 from a 325-0-325VAC secondary
He who dies with the most tubes... wins
Baltar
Posts: 37
Joined: Mon Apr 14, 2008 10:36 am
Location: Austria

Re: 5F6a importance of output configuration

Post by Baltar »

@Steve
thanks a lot for the helpful link.
i like the electro harmonix 6v6 a lot and like to try those first in my build.
they are indeed voltage critical, other than eg jjs

@rp
good point, i will do

@tubeswell
don't tempt me :)
idea on one pair of 6v6 was to save some power and weight(smaller trans
if possible) still haven't decided for the pt yet, but am thinking of a 290dex
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