# move over Marshall...there's a new Deputy in town!!



## bolero (Oct 11, 2006)

I recently managed to acquire an amp I have been searching for for quite some time. They are pretty hard to come by; not only because of the rarity, but also because they sound so good ( apparently  )

they were built by legendary amp designer Gar Gillies of Garnet fame. He had always used his own unique designs, not copying Fender or Marshall. indeed he started making amps much before Marshall: he was building PA systems in the '50s


I guess eventually he relented & made a circuit similar to a plexi. but he added a central input that internally ties the 2 front channels together: the "mix" input. no need for a daisy chain cable!! pretty neat

I'm hoping it sounds something akin to a 50w plexi

this one was dead when I got it, but my attitude is....if it's an old handmade tube amp, it will be robust & possible to fix.....worst case: maybe a blown tranny. ( don't get all excited, I am talking electrical components here  )

chassis pic:












so I got it home, pulled it apart & inspected with my rudimentary knowledge....a bright light revealed no burn marks on anything, or obvious leaking caps. lets check the internals fuses...hmmm. smokey glass on one, not sure about the other but it looks broken. so definitely 1 or 2 blown internal fuses











next I pulled the main fuse on the front of the amp...blown too; it's pretty clear why the amp won't power up












...so the big question is: why did all these fuses blow??

I dropped it off with my amp tech this week, to give it a once over. I hope the transformers are ok, my gut feeling says power tube but I have my fingers crossed.

oh, speaking of power tubes, I can just make out the remnants of lettering that said " Mullard EL34 made in great Britain" ...woot!!

I think I found the culprit....there is a cracked resistor in where one of the PT leads hooks up to the rectifier diode area ( it's barely visible as it looks like a color band )













there was a spider living in there at some point, who was quite well fed  actually found his carcass in there too


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## keto (May 23, 2006)

Huh, how about that? I never knew such an animal existed. Thanks for the education, and good luck getting 'er fired up.


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## jb welder (Sep 14, 2010)

Good eye on that resistor! Appears to supply power to the bias feed (120K2W) if this is the right schematic: http://www.webphix.com/schematic heaven/www.schematicheaven.com/bargainbin/garnet_g100_deputy.pdf
So with no negative bias voltage for the power tubes, they would over-conduct and probably cause the fuse to blow. Whether the power tubes would be ok or destroyed is hard to say. Their screen resistors (470 ohm2W) should be checked as they often go along with the power tubes.
Those three fuses are all doing only one job, acting as a mains fuse. The internal one with the clips is someones add-on. The original pigtail fuse blew and they just added a standard fuse across it with those clips, rather than soldering in a new pigtail type. 
The internal fuse is wired in series with the external fuse holder. It is sometimes referred to as an "idiot" fuse. It's purpose is to be a backup fuse and blow in case some "idiot" replaces the blown external fuse with an oversize fuse or tinfoil.
Hopefully your transformers are both ok. Transformer failure is very rare except in cases of blown fuses being replaced with oversize/tinfoil.


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## Scottone (Feb 10, 2006)

Cool amp. Power transformer appears to be a replacement (note the pre-cut hole for a laydown type transformer) but not sure about that.

If you decide not to have it fixed, let me know...I'm always looking for a project amp


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## WCGill (Mar 27, 2009)

Since the schematic shows 6L6GC's and the amp has EL34's in it, the screen resistors should be 1K 5w. As well the grid stoppers should be upped in value. I've seen a Garnet Session Master before that had EL34's with 6L6C circuit values.


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## jb welder (Sep 14, 2010)

WCGill said:


> Since the schematic shows 6L6GC's and the amp has EL34's in it


Oops, missed that part :zzz:. Then in addition to the changes WCGill mentioned, the bias will probably need adjustment. EL34's in a 6L6 circuit will be biased quite cold.


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## bolero (Oct 11, 2006)

got the amp back, it sounds great!!!

I will ask the tech about EL34 vs 6L6...actually I wonder if someone just plugged those EL34's in there & that's what caused problems?

here is it aside it's cousin...the Marshall & the Deputy


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## Scottone (Feb 10, 2006)

Cool..was the broken resistor in the bias circuit the problem? Just curious.



bolero said:


> got the amp back, it sounds great!!!
> 
> I will ask the tech about EL34 vs 6L6...actually I wonder if someone just plugged those EL34's in there & that's what caused problems?
> 
> here is it aside it's cousin...the Marshall & the Deputy


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## bolero (Oct 11, 2006)

yes that resistor had to be replaced, along with some other components in there, I think one or more of the diodes as well

but it is biased & setup for EL34's 

not sure why the amp had problems in the 1st place, maybe someone ran it thru the ext jack by accident or something? the power tubes were fine. I'm not sure if the resistor just broke, or if it overgeated etc


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## ezcomes (Jul 28, 2008)

those re supposed to be pretty sweet amps...shop here in town had a Deputy II for awhile...just didn't have the cash...


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## bolero (Oct 11, 2006)

ah that's too bad...

ps I found out the difference between the models

Deputy I = 50w
Deputy II = 100w

and the Deputy II has 2 output transformers, which is cool. the first few 100w marshalls were like that too


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## Scottone (Feb 10, 2006)

Hard to say, but I've heard that bias circuit failures are common with some Garnets due to an under-spec'ed capacitor. They used the same bias circuit for all of the amps apparently.

I converted my Garnet to adjustable bias, which is a common mod.



bolero said:


> yes that resistor had to be replaced, along with some other components in there, I think one or more of the diodes as well
> 
> but it is biased & setup for EL34's
> 
> not sure why the amp had problems in the 1st place, maybe someone ran it thru the ext jack by accident or something? the power tubes were fine. I'm not sure if the resistor just broke, or if it overgeated etc


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## bolero (Oct 11, 2006)

hey, thx for the info!!


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## ThePass (Aug 10, 2007)

Cool thread, and GREAT pics!! Nice amps too, lol. Should add that.


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## nonreverb (Sep 19, 2006)

Repaired one of those not long ago. Unfortunately it had a blown output tranny


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## bzrkrage (Mar 20, 2011)

Meanwhile.....back in Calgary, 8+ years later......
*A Deputy has come into town......*
Scored it last night, will look under the hood over the weekend to see what’s what.
@jb welder , any chance on an updated schematic site (having a bit of trouble...)
@bolero and the pics are gone, would love to see the guts shots.


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## jb welder (Sep 14, 2010)

bzrkrage said:


> @jb welder , any chance on an updated schematic site (having a bit of trouble...)


Here you go:
http://www.thetubestore.com/lib/thetubestore/schematics/Garnet/Garnet-G100-Deputy.pdf


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## bzrkrage (Mar 20, 2011)

So, she's a little sad, made some noise (variac slowly increased, but there's something wrong.)
So off to Uncle Mike at L&M South Calgary for a little TLC.


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## MarkM (May 23, 2019)

Cool that looks like it's been in my shop for 20 years.

I'm following this thread.


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## player99 (Sep 5, 2019)

That is cool. Is it heavy?


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## bzrkrage (Mar 20, 2011)

player99 said:


> That is cool. Is it heavy?


Suprisingly not too heavy.
I will weigh it to find out.
Oh, and with the potentiometers inside, it dates at a1972.


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## Pronto (Mar 28, 2020)

I just picked one up in December. A 50 watt. This is actually a considerably better sounding amp than I expected... and I say that having played professionally for years with a Garnet Pro and also have a Gnome which makes a great practice amp, along with my new Deputy purchase. 

It's like every classic rock song I tried to make sound right with other amps and a pedal (ts808, ibanez 80's pedals, tech 21 etc... ) now doesn't need a pedal. Just dial the two channels up to about a quarter volume and voila! instant plexi! 

Since it's so freakin loud, however, I've been using an old Tom Sholtz attenuator, which works great, but makes it easier to be hard on tube life. I was also having some red plate issues after 15 or so minutes when cranked and my tech (who's done amps for Sting and other major artists) tells me that with modern wall power, it is causing the amp to run too high a plate voltage and not have a bias voltage issue like I assumed. 

His advice to me was either play at lower volume settings (no fun, no plexi distortion), or get a variac. Seems like the 50 watt models were already built to run hotter than the schematic says and designed to coax more like 65 watts out of them. Great, but really hard on the amp and tubes. So I'm now in search of a variac to get input volts down to 100 volts which will prevent red plating and allow it to make that nice classic overdrive at lower volume levels. (apparently a Van Halen trick). Great Great Amp!!


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## laristotle (Aug 29, 2019)

Pronto said:


> get a variac


A friend of mine has a coupla' plexis and did this. He's happy that he did.


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## bzrkrage (Mar 20, 2011)




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## MarkM (May 23, 2019)

Is that the amp back from the shop?


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## bzrkrage (Mar 20, 2011)

MarkM said:


> Is that the amp back from the shop?


Yes!


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## MarkM (May 23, 2019)

Cool, is that the original Cabinet with that amp?


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