Showman Amp

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Stevem
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Y

Post by Stevem »

Fender never made a Blond 2-15" horizontal speaker cabinet, those must be 12" JBL drivers if they are original !
The first 2-15" cab came about in the black Tolex era, and the cab stood verticle.
When I die, I want to go like my Grandfather did, peacefully in his sleep.
Not screaming like the passengers in his car!😊

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MakerDP
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Re: Showman Amp

Post by MakerDP »

Ah bummer... those tube charts often came with a letter stamped on them that correctly identifies the year. Using transformer date codes or chassis serial no's only tell you it wasn't made before that date, but it could (likely) have been made in later years as people mentioned before parts were usually just pulled at random. But that stamp, if there was one, is really the only way to nail the year precisely. It also identifies the circuit name.

Perhaps a previous owner tore it out to take it down the the music store and show them what tubes they needed instead of just bringing in the whole head???
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rp
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Re: Showman Amp

Post by rp »

Suggestions on what to do with it?
Play the shit out of it.

Yes, I know, it's 80W, it's loud, and it's 2017 :cry:
gldtp99
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Re: Showman Amp

Post by gldtp99 »

Something's not adding up here.

It has transformer p/n's that were used in the Very Rare 7355 output tube Fender amps.
And look at the wiring of the output tube sockets------Pin 5 (cathode/beam plates on 7355 pinout) is connected to ground by a braided wire. And the 1.5k Control Grid resistor is connected across pins 1 and 6 (Pin 6 is the Control Grid on a 7355).

7355 data sheet: http://frank.pocnet.net/sheets/135/7/7355.pdf

But the OP states that the amp runs 6L6GC x 4------ I believe that 6L6GC's would not operate in this amp at all.
OP also states that the amp uses 12ax7 x 4------ It should be three 12ax7's and one 12at7 in the PI----- this
is easy to confuse and the amp would still operate with a 12ax7 in the PI.

I own a Blonde, Transitional, BF, AA763 Showman that runs 7355 output tubes---- here it is with the matching original Blonde 2 x 15 speaker cab loaded with JBL's:

[IMG:800:600]http://i46.photobucket.com/albums/f112/gldtp99/Showman%207355/7355Showman004.jpg[/img]

The OP states that the amp runs 6L6GC x 4 and is very loud----- I don't see how this can be true---- Is it possible that the OP doesn't know the difference between 6L6GC and 7355 tubes ? 7355's are sized more like 6V6's.

How could 6L6GC's even operate with the output tube sockets wired for 7355's ?

Some of the 7355 amps have been converted over to run 6L6GC's but the output tube sockets have to be re-wired to 6L6GC specs------ this amp's output tube sockets are wired for 7355's.

Another thing is that there is no Mid pot on the Vibrato channel (the same as my 7355 Showman)----- every 6L6GC BF Showman I've ever seen has the Mid pot on the Vib channel (I currently have two BF AB763 Showman heads-- a '66 and a '67)

Thoughts ?
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ToneMerc
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Re: Showman Amp

Post by ToneMerc »

gldtp99 wrote:Something's not adding up here.

It has transformer p/n's that were used in the Very Rare 7355 output tube Fender amps.
And look at the wiring of the output tube sockets------Pin 5 (cathode/beam plates on 7355 pinout) is connected to ground by a braided wire. And the 1.5k Control Grid resistor is connected across pins 1 and 6 (Pin 6 is the Control Grid on a 7355).

7355 data sheet: http://frank.pocnet.net/sheets/135/7/7355.pdf

But the OP states that the amp runs 6L6GC x 4------ I believe that 6L6GC's would not operate in this amp at all.
OP also states that the amp uses 12ax7 x 4------ It should be three 12ax7's and one 12at7 in the PI----- this
is easy to confuse and the amp would still operate with a 12ax7 in the PI.

I own a Blonde, Transitional, BF, AA763 Showman that runs 7355 output tubes---- here it is with the matching original Blonde 2 x 15 speaker cab loaded with JBL's:

[IMG:800:600]http://i46.photobucket.com/albums/f112/gldtp99/Showman%207355/7355Showman004.jpg[/img]

The OP states that the amp runs 6L6GC x 4 and is very loud----- I don't see how this can be true---- Is it possible that the OP doesn't know the difference between 6L6GC and 7355 tubes ? 7355's are sized more like 6V6's.

How could 6L6GC's even operate with the output tube sockets wired for 7355's ?

Some of the 7355 amps have been converted over to run 6L6GC's but the output tube sockets have to be re-wired to 6L6GC specs------ this amp's output tube sockets are wired for 7355's.

Another thing is that there is no Mid pot on the Vibrato channel (the same as my 7355 Showman)----- every 6L6GC BF Showman I've ever seen has the Mid pot on the Vib channel (I currently have two BF AB763 Showman heads-- a '66 and a '67)

Thoughts ?

I think you nailed it, it's a 63' transitional 7355 Showman.

TM
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martin manning
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Re: Showman Amp

Post by martin manning »

Clearly you are correct about the socket wiring. Maybe the OP did not notice the output tube type is not 6L6... the envelopes are similar. Maybe take a closer look? I wonder if the missing tube chart has anything to do with it, like the head box is not original to the chassis?
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MakerDP
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Re: Showman Amp

Post by MakerDP »

Agree... that could definitely explain the missing tube chart.
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ToneMerc
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Re: Showman Amp

Post by ToneMerc »

MakerDP wrote:Agree... that could definitely explain the missing tube chart.
I was beginning to think the same thing as to why the chart was removed.

TM
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ToneMerc
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Re: Showman Amp

Post by ToneMerc »

So, for all practical purposes it's a four 7355 tube Bandmaster with a Showman badge, how cool is that!

TM
gldtp99
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Re: Showman Amp

Post by gldtp99 »

ToneMerc wrote:So, for all practical purposes it's a four 7355 tube Bandmaster with a Showman badge, how cool is that!

TM
That is a very good description of the 7355 Showman amp---- My AA763 7355 Showman doesn't have the punch/depth of a good 6L6GC BF Showman.
I've always felt that putting this amp into regular use would be kind of pointless---- I'd be better off just playing one of my BF Bandmasters (getting about the same power level as the 7355 Showman) and I wouldn't be using up the rare 7355 tubes.
Fender's 7355 amp production was short lived---- I think it was an idea that looked good on paper, some amps were produced/sold, but it really didn't pan out in the real world. The 7355 data sheet says two 7355's in A/B push/pull at Fender-ish voltages will put out 40 watts (so four would give 80 watts output)-----But mine never has seemed to be putting out 80 watts--- I've tried many good testing 7355's in it and it seems to feel like a consistant 50-55-ish watt output------ maybe a little more than a BF Bandmaster but not like a BF 6L6GC Showman at a rated 85 watts output.
I've never seen the PT current specs but the PT's in these (mine is an Export with a multi voltage PT primary) are not the same size as the 125P34A PT used in the 6L6GC BF Showman----- the PT in mine is the same physical size as a BF Bassman/Bandmaster 125P7D PT.
However someone played the 7355 Showman I have quite a bit before I got it----- It isn't a "Closet Queen" amp at all, it has the usual tolex tears, etc that a well used amp will collect.......... gldtp99
Stevem
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Post by Stevem »

I did not look close enough at those output tube sockets, but indeed if 6L6 tubes had been run in that amp then all they would have done is sat there and glowed with there heaters on and no output coming from the amp!

I have never seen a Fender amp that used these 7355 outputs, but could these Showmans be built this way be part of the puzzle as to due to a mishap Fender made blonds with OTs with only a 4 ohm output winding when the amp neede 8 ohm?
When I die, I want to go like my Grandfather did, peacefully in his sleep.
Not screaming like the passengers in his car!😊

Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
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ToneMerc
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Re: Y

Post by ToneMerc »

Stevem wrote:

I have never seen a Fender amp that used these 7355 outputs, but could these Showmans be built this way be part of the puzzle as to due to a mishap Fender made blonds with OTs with only a 4 ohm output winding when the amp neede 8 ohm?
From what I read Leo Fender had trouble getting larges lots of what he called good 6L6 tubes, so as an alternative they tried the 7355 tube. Obviously this was a short lived experiment.

TM
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martin manning
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Re: Showman Amp

Post by martin manning »

7355 Pa max is 18W vs. 6L6's 30W. Other things being equal that says a 7355 amp can produce only 60% of the power that a 6L6 amp can.
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martin manning
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Re: Showman Amp

Post by martin manning »

Nice! Yes 6V6 size. Do you know what plate voltage they are running?
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