New '65 Showman

Jon Light · From: Saugerties, NY

This baby arrived today. Like, wow.
My biggest frustration is that I have to keep the leash on in my apartment. I won't be able to take it out and let it run for a little while. But there are no disappointments here. It is amazingly quiet and glitch-free. It is real good shape except that somebody installed a small fan in one side so it is, by no means, in virgin condition. Not a concern.

But I immediately have some questions about care and feeding.

First--like I said, it is quiet, clean, loud free of pops and crackles. Is there any reason why I should take it to a tech for the re-cap and tube job I assumed would be necessary? Why should I mess with it? What should I listen for? If it sounds as clean as I think it does, should I just assume that it probably has been rehabbed in the not so distant past?

Also--should I always turn it on in standby mode? If I'm going to walk away for 20 minutes, should I go to standby? Or should I turn it off? What's the best approach for long life and prosperity?

Although I don't have any 4 ohm speakers, is this rated for 4 ohm?

Probably more questions to come. Thanks.

Bob Knight · From: Bowling Green KY

Jon,
In reference to the standby question: When does a light bulb usually burn out?

Regards,
Bob

Steve Feldman · From: Central MA USA

I see your point, Bob. In fact, there were times that I just left computers on forever instead of powering them down. But an amp puts out a lot more heat than a computer. Doesn't this factor into things at all?

Rick Johnson · From: Wheelwright, Ky USA

Congrats on the Showman.
To help answer your question, I recommend the
following. If you know a friendly tech, let
him look at it. The electrolytic caps in it are 35 years old. If it hasn't been re-capped. If not, do the cap job. Have matching
quad of 6L6GC's installed and at least change the phase inverter tube 12AT7 and the
12AX7 on the second channel. The others are
important but only if the budget allows.
Have the bias set to about 35 miliamps on the tubes. The tech will get a reading of
70 amps on each pair. Thats correct.He will
know that. Now the amps refreshed and will
produce the way it did in '65.
Put the amp in standby when not being used
for a few minutes. That keeps the tubes up
near operating temp. Ready to go.
Also when you power down, take to standby for a few minutes then turn off.
As far as the ohms are. The Showman has a
8 ohm output tranny. Two 8 ohm cabs take it to 4 ohms total. It can handle it fine.
I'm not the best tech in the world, but
when you own several amps it pays to learn
to do routine maintenance. One more thing
be sure to have a three wire cord installed
on it. Email me with any particular questions
you have. I love to talk about old Fenders.
Remember, inside the amp there is 400/500
volts of charge even when unplugged.
Be carefull.

Good luck.
Rick

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Rick Johnson

Jon Light · From: Saugerties, NY

Yep, Bob. I see it now.
Rick. Thanks. I definitely appreciate the offer to share your Fender experience and knowledge.
So I'm still wondering, though--if the amp sounds good, sounds quiet, do I assume that it probably has fresh caps? Do caps just die or do they deteriorate slowly? I read on one of the really good tube amp websites about how these caps were only designed to last, like, 10 years or something? And if you got more out of them it was because they were just made too well. And that they even have a limited shelf life. Interesting.

Right now the amp has 4 6L6WGB.

Obviously, if I can save the $$ and leave things be, well, I'm no fool.

Question--my Boss RV-3 has two outs. What would happen if I ran one to each channel of the Showman, using this for more tone-tweaking control? Is this over stressing the amp? Is it shortening the life of tubes or transformer or anything? (This is just idle thinking here).

Another question--this amp has no piece of paper in it. The only thing I can find is this number stamped on the chassis--A05636.
Is this just a serial # or is this any kind of significant identifier?

I'm just fishing for knowledge. I appreciate it all!

---Oh, about your last warning, Rick--rest assured. I am a fearless tinkerer but not with electronics. I have a healthy fear. I used to worry every time I turned on a Fender because it felt like you were sticking your hand into live voltage when you groped around the rear for the power switch. I blessed the man who invented the front panel on/off switch. No sir, I ain't messing around in there.

[This message was edited by Jon Light on 10 February 2001 at 06:25 AM.]

Jerry Erickson · From: Atlanta,IL 61723

Hi John,
For finding out what impedence the amp should run at, does the front panel of the amp say Showman Amp or Dual Showman Amp? If it says Dual Showman, then it was set uo to run at 4ohms.Another way to find out is to look at the output transformer and red the numbers that are stamped on it. It's the big transformer in the middle of the amp.It's
possible that the number could be 125A29A for a dual showman or 125A30A for a single Showman. Hope this helps out. Have fun with your new amp.
Jerry

Rick Johnson · From: Wheelwright, Ky USA

Jon, Lets say you just got a '65 Vette.
Looks good, runs good. Why mess with it.
My point is to have peace of mind about
the Vette, a tune up is in order. What if
the points are about to go out or you have
a distributor thats cracked and could let
moisture in. You will be stranded.
Same as the Showman. You are just verifying
its physical condition.
Caps wear out. They contain 400/500 volts
of energy and can leak DC into the preamp.
They can burst and short out of damage
the power tranny or output tranny. Technology
was primitive in '65. New caps are better.
You won't get stranded.
Your amp is probably a AB763 the number you
see on the chassis is the S/N.
As far as using both channels. Try it.
I've seen bands play bass and vocals thru one. Showmans are a workhorse.
On the tube quesion, again the Vette comparison. All the plugs should be the same
make and type. The tubes although the same
make and type might not be matched for
optimum performance. This allows the tech to
set the bias and be assured the amp power
section is well balanced. The bias control
affects all power tubes. If tubes are not
matched, they could be running cold or too hot. Bad. The amp will lose tone and harmonics and be sluggish. I'd better quit
talking so much.
Thanks and enjoy the amp. Its a Classic.

Rick

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Rick Johnson

Al Marcus · From: Cedar Springs,MI USA (deceased)

Jon, you lucky guy! I had a Fender showman with a single 15 inch JBl spkr and I believe it was the best amp I ever owned. I had a twin reverb too with 2 JBL 12 speakers and it was pretty good too, but the showman had more bass for one thing.I liked the separate head and speaker, a little easier to carry....al

Glenn Austin · From: Montreal, Canada

You need to get a copy of Aspen Pittman's Tube Amp Book. A good read with lots of info on Fender amps.

Pete Burak · From: Portland, OR USA

Hi Jon,
Concerning your RV-3 question. I tried running the stereo outs of my RV-3 to channel 1 and channel 2 of my Fender Twin Reverb. It had a "cancelling" effect.
I set the reverb channel to normal playing volume (and tone) using the mono output on the RV-3, then I plugged in the other output to the non-reverb channel, when I turned up the volume on the non-reverb channel the overall volume (and tone) would decrease.
This was also the case when I ran the stereo outs from my Goodrich volume pedal to the 2 separate input channels of the Twin.
But, when using the 2 channels for steel and guitar (2 separate instruments), they functioned independantly of each other. Weird?!?!
I don't know if this is normal or not, but it didn't seem to hurt anything, so maybe you could try it and let me know if you have similar results.
What is the Showman?... a 2 channel head and a 15" cab?... built in reverb?
I've found lots of cool combos of delay and reverbs using the Twins onboard reverb and the RV-3 delay and/or reverb.
Have fun with it!
Pete

ps
Anyone ever use a Fender Bassman for steel. There's one in the local paper for $175.

Dave Van Allen · From: Doylestown, PA , US , Earth

I have 2 BF Bassman Amp heads- each with a 2x12" closed back cabinet. One is original I dunno what maker fender speakers , the other is loaded with JBLs I dunno what model #. Both sound great... the JBL cab is more "Brittle". Used one or both with a delay (no verb) for ambience.
I like 'm jes fine!! (they need some maintenance though- prolly caps and definitely tubes)

Tom Brumley uses a pair (or has in recent years) of the Bassman ReIssues- the 59 combo style, I think he has 'em loaded with 15's but don't quote me on that

[This message was edited by Dave Van Allen on 12 February 2001 at 07:00 PM.]

Matt Farrow · From: Raleigh, NC, USA

There is a big difference between "reverb" and "non-reverb" Fender amps, and that is that the "reverb" amps have an extra tube stage used to mix the reverb pan signal with the dry signal from the Vibrato channel. Usually a tube stage inverts signal phase 180 degrees, and on these Fenders the Normal channel is 180 degrees out of phase with the Vibrato channel. So therefore on Twin Reverbs, Super Reverbs, Pro Reverbs, etc. if you connect the same signal to both channels, they will more or less cancel out.

On "non-reverb" Fenders, the channels are in phase with each other. So if you connect the outputs of your RV-3 to your Showman, you can blend them to taste. You may not get any benefits from this (you might even overdrive the amp, which you may not like) but it will work OK. Bandmasters, Bassmans, Showmans (not the Dual Showman Reverb TFL-5000,) etc. will work with their channels "bridged" together.

Fender tube amps that work pretty well for steel: BF & SF Bandmaster, Bassman, Showman, Dual Showman, etc. You want to stay at or above 40 watts or so. There are a few amps that are really great for steel: BF & SF Vibroverb (you'll have a hard time finding one of these, because SRV played one so guitar players want 'em.) and SF Vibrasonic (100W combo with a 15".) I like a Fender Twin Reverb for E9th, though they don't have enough bottom for some folks. Put a 15 in there and it's a good steel amp, though.

My 2¢
Matt Farrow
Pharaoh Amplifiers

Bob Carlson · From: Surprise AZ.

If It ain't broken, don't fix it. If you don't hear any bacon frying with the vol up to six or so I wouldn't let no one touch It. And maybe the reason It sounds so good Is because of that cooling fan someone instaled. Mostly because of the transformer, tube amps run HOT.
What I'm going to say here Is what I read In "Guitar Player Mag". What ever it is a tube is made of gets hot and over a Period of time they self destruct. When you turn your amp on for a half hour at a time It lets this matreial build up on your tubes and It starts frying bacon. By putting It In standby It prevents this. So If you're not going to use It for eight hours or so turn It off, but If It will only be around four hours put It In standby. And DON'T put It's back to the wall because It needs that cool air.

Bob Carlson

Uff Da!

Jon Light · From: Saugerties, NY

I'm getting some great info here. Thanks for all of it.
This is a non-reverb amp. I don't know yet if the bridged channel mode is something that interests me or not but now I know I can mess with it without blowing up the amp. That's a real good bit of info, Matt, explaining why Pete B got the results or lack thereof that he got from his twin.
The fan in this amp, BTW, is not functioning--in fact the blades are gone. Just the casing and little motor.

One thing nobody mentioned--the smell! There's something about the smell of warm tubes on a winter day---or let me mangle the great line from Robert Duvall---

I love the smell of glowing tubes in the morning. Smells like.....like....TONE.

Max Laine · From: Pori, Finland

Is there a reason why you shouldn't use a fan cooling those hard-working tubes? I have a '66 Showman head I'm gonna build into a combo with a 15" and I also have a fan ready... should I put it in there?

Max

Ricky Davis · From: Bertram, Texas USA

Absolutely put a fan in and use it if it's there.
Keeps the tubes consistant and therefore the sound will be consistant; and tubes will last longer.
And use the standby when turning on the amp; and then use the standby when your on a break; then use the standby for 1 minute before you turn off. These tips were given to me by Redd Volkaert and nobody knows the tube amp like "The Man" himself.
You can actually have that tube amp functioning very well for a long long time; following some of these tips.
Ricky
Ricky

Rick Johnson · From: Wheelwright, Ky USA

Rick,
I have to give my .02 on the cooling fans.
They will pull in dust, the noise is always
there. Hot, or operating temps with tubes
is OK. They have filament heaters in them
so they will get hot. They cool by convexion.
The excess heat it drawn into the wire mesh
grid in the roof of the amp. In fact the tube
are cooled while the guitar is being
played thru them. The cycle is completed. Only at idle is there a build up
of heat. Thats why the standby is there.
It cuts out the filament heaters and lets the tubes stay warm. Its true that hot tubes
are rough on the power tranny, but that heat
is from a improperly bias tube. Old amps
are tough. They can take it. Power trannys can last 40 years and do. Hot, is good. I certainly don't advocate altering vintage amps.
Still friends?

Rick

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Rick Johnson

Ricky Davis · From: Bertram, Texas USA

Rick; I'm gunna have to go with you on this one. I don't have a fan in my Twin; and I have'nt had a problem with it at all in 3 years(that I've been playing this one). I play every night and day through it and just learned recently about the standby; so I'll have to say your probably(well you are)Right about the tubes being self resiliant.
This info was passed to me and makes since; but Redd did say>not a good idea to change the originality of it>just if you plan on using it forever for yourself. Rick you have got the thing dialed in here on this issue; and we really appreciate your very good advice and knowledge my friend.
"Keep it comin"
Ricky

Dan Tyack · From: Olympia, WA USA

I don't think using a fan is all that usefull. But using the standby is definitely key to long tube life. The most important is turning the amp ON standby before turning it on. This will greatly increase the life of the tubes.

One thing I have notices since becoming a tube amp nut: I am not dependent on reverb. More often than not, I will use my Showman with no (or very little) reverb. I also prefer digital reverb (very sparingly) to the spring variety. For rock and roll, the reverb takes away from the presence of the amp.

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www.tyacktunes.com

Rick Johnson · From: Wheelwright, Ky USA

Rick,
This was a good thread.
I love the feedback. Thanks to the Forum.

Rick

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Rick Johnson

Jim Mathis · From: Overland Park, Kansas, USA

Jon,

If a 35 year old amp is clean and quiet, you can assume it has been recapped. I wouldn't worry about it until you start hearing some hum or noise.

It's like the '65 Vette that run greats. If it runs great, it has definately been tuned-up recently.

Matt Farrow · From: Raleigh, NC, USA

About the use of a fan in a tube amp:

Tubes are designed to run HOT. The point of thermionic emission (the temperature at which vacuum tubes actually start to work) is somewhere around 1200 deg. F. The heat you feel is actually transmiitted thru a vacuum, which is a terrific insulator. Cooling the outside surface of a tube will have NO effect on the tube either detrimental or beneficial. Tubes will operate with bulb temperatures down to 0 deg F and below!! BUT - the other components on your amp are not so hardy. Older transformers can short if overheated, caps can dry up, resistors can open up or change value, etc. The point of using a fan is to keep the other parts of your amp from being damaged by the heat of the tubes. If you put a fan in your Fender head, I suggest making a new cab for it so you don't have to hack the old one (or if you're Jon Light, use the one you got) and set the fan up to blow outside air in the cab, across the power tubes and power transformer (the left side when looking in the back of the amp.) But honestly, if the amp uses a solid-state rectifier (most 100W Fenders do) then I wouldn't nother with the fan. A tube rectifier pulls a lot of current thru the power transformer and burns most of it off as heat. Tube rectifiers can add a wonderful tone quality to the dynamics of an amp, but they are extremely impractical and unreliable. Fans in a Twin? Nah. But in a Deluxe or a Super, maybe. Certainly don't enclose the back of the cabinet or put it tight against a wall while in use.

My 2¢
Matt Farrow
Pharaoh Amplifiers

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Matt Farrow
Marlen 9-string 6+2
Kustom K150

http://surf.to/pharaohamps

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