Bassman 5b6

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M Fowler
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Re: Bassman 5b6

Post by M Fowler »

Yeah I am quite sure most of us could easily build some type of 18 watt varient for $700-$800 price range including cabinet. Komets are nice amps and I am sure the 19 is well built according to the reviews.

Mark
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M Fowler
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Re: Bassman 5b6

Post by M Fowler »

New 5b6 bassman project using custom Princeton size chassis into Princeton style head cab blonde. :) This project was relatively cheap using ebay Hammond organ PT and $30 4k/4ohm 35w fender style OT.

Mark
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M Fowler
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Re: Bassman 5b6

Post by M Fowler »

The layout is terrible and I need to redo it, sorry.
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xtian
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Re: Bassman 5b6

Post by xtian »

I love a simple circuit!
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M Fowler
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Re: Bassman 5b6

Post by M Fowler »

Yeah this is a simple circuit but I love the tone of an octal preamp :)

I was going to build the amp PTP like my first version but decided I wanted to go with a tone board this time since it was a much larger chassis.

Mark
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rp
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Re: Bassman 5b6

Post by rp »

Very nice, these ancient amps have a lot of cool tones to offer. Did you try the grid leak set-up too and didn't like it, or just passed on it? If the latter, you should try it, it very different, super detailed and dynamic, extra twangy, brings out finger and string noise - but a good and different sound. Have you let it rip, any trouble with that 6SC7s and microphonics? All the internet warnings on staying away from 6SC7s is pretty valid I found. It's going to cost me some dough hunting down 2 quiet ones, but I wanted to be a purist. I finally got my 5C8 finished and will post it soon. This can be stone-age amp week.
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Colossal
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Re: Bassman 5b6

Post by Colossal »

rp wrote:Very nice, these ancient amps have a lot of cool tones to offer. Did you try the grid leak set-up too and didn't like it, or just passed on it? If the latter, you should try it, it very different, super detailed and dynamic, extra twangy, brings out finger and string noise - but a good and different sound.
RP, can you clarify what you mean? Which grid leak set-up?

Thanks,
Dave
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rp
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Re: Bassman 5b6

Post by rp »

Colossal wrote:RP, can you clarify what you mean? Which grid leak set-up?
Oops, my bad, didn't recheck the schematic. I thought all the earliest Fenders were grid-leak on the first stage. I'm curious why the 1952 Bassman got cathode bias while its brethren got grid-leak, does grid leak not pass as much bass as cathode bias with a 250mF cap? Distorts more? I still recommend trying it as it sounds really good and different.
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M Fowler
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Re: Bassman 5b6

Post by M Fowler »

I'm using a NOS 6SC7GT tube. No microphonics.
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rp
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Re: Bassman 5b6

Post by rp »

M Fowler wrote:I'm using a NOS 6SC7GT tube. No microphonics.
Mark, my glass ones are a little better too for microphonics but less lively (or likely just less bright) than the metals. The glass I got are pulls too and could be weak. What brand of tube you got?
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Colossal
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Re: Bassman 5b6

Post by Colossal »

rp wrote:
Colossal wrote:RP, can you clarify what you mean? Which grid leak set-up?
Oops, my bad, didn't recheck the schematic. I thought all the earliest Fenders were grid-leak on the first stage. I'm curious why the 1952 Bassman got cathode bias while its brethren got grid-leak, does grid leak not pass as much bass as cathode bias with a 250mF cap? Distorts more? I still recommend trying it as it sounds really good and different.
Thanks! Yes, those old octal amps sound fantastic.
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M Fowler
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Re: Bassman 5b6

Post by M Fowler »

rp wrote:
M Fowler wrote:I'm using a NOS 6SC7GT tube. No microphonics.
Mark, my glass ones are a little better too for microphonics but less lively (or likely just less bright) than the metals. The glass I got are pulls too and could be weak. What brand of tube you got?
RP, I'm using Haltron 6SC7GT

Mark
printer2
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Re: Bassman 5b6

Post by printer2 »

What is the supply voltage?





Oh wait a minute, they are on the layout, never mind.
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rp
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Re: Bassman 5b6

Post by rp »

M Fowler wrote:RP, I'm using Haltron 6SC7GT
I was going to post and ask about those. There are several web sellers with stocks. Does yours state a country of origin? The only old USA GTs I've seen have been smoked glass and Raytheon and Tungsol brands, the Raytheon probably a Tungsol too. I'm thinking those Haltrons are a 60-80s Euro/East Euro make? Any clue?
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M Fowler
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Re: Bassman 5b6

Post by M Fowler »

rp wrote:
M Fowler wrote:RP, I'm using Haltron 6SC7GT
I was going to post and ask about those. There are several web sellers with stocks. Does yours state a country of origin? The only old USA GTs I've seen have been smoked glass and Raytheon and Tungsol brands, the Raytheon probably a Tungsol too. I'm thinking those Haltrons are a 60-80s Euro/East Euro make? Any clue?
I bought my tubes from Tubedepot.com NOS-6SC7GT 13.95 each.

Unless somebody knows you would have to call tubedepot to find out more info.

Mark

Found this on another forum:
Haltron was a tube marketer rather than a manufacturer,
similar to Xaerix, National (OK, National did make
SOME things) , IEC, Calvert Electronics ("Gold Monarch"),
and Realistic.

Haltron sold tubes from all over. As with other marketers,
if you're smart and observant enough to be able to determine
who actually made the tube, you may find some hidden
treasures amongst Haltron tubes. 30 years ago, Haltron
didn't give a flying hoot who made what tube so long as
the price was right, and back then, not too many cared
so long as it wasn't WE or Eimac. Of course the reverse
applies, too, they might be Eastern European or Japanese,
but if the price is right, they might still be a good deal.

--
Ned Carlson
SW side of Chicago, USA
www.tubezone.net
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