Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: TubeGeek on April 11, 2014, 10:10:50 pm

Title: On the bench: Garnet Pro and Reverb Amp's
Post by: TubeGeek on April 11, 2014, 10:10:50 pm
On the bench tonight is a Garnet Pro.


Thought some of you would like to see the guts.
Title: Re: On the bench: Garnet Pro
Post by: SILVERGUN on April 11, 2014, 10:17:32 pm
 :huh:

Nice!,,,what were the chances of you having one of those laying around...

I gotta get me one of those "sound fountain"s
Title: Re: On the bench: Garnet Pro
Post by: TIMBO on April 11, 2014, 10:25:19 pm
Thanks Tubegeek, That's AWSOME, very clean inside. Are able to pinpoint a specific schem................

For me, the STINGER is the need to know, as I tried it and it didn't work very well. Thanks
Title: Re: On the bench: Garnet Pro
Post by: TubeGeek on April 11, 2014, 10:49:44 pm
:huh:

Nice!,,,what were the chances of you having one of those laying around...

I gotta get me one of those "sound fountain"s


Being that I am in Canada I do see a few of these come across my bench every so often.  I have not been able to purchase one yet.  I haven't been actively pursuing one either. That might change.  Still testing it out.


There is no actual problem with this amp.  All that happened was one of the 12ax7's slipped out of it's socket in the little metal cage so it wasn't making contact. Pushed it back in and it came to life.
Title: Re: On the bench: Garnet Pro
Post by: TubeGeek on April 11, 2014, 10:52:06 pm
Thanks Tubegeek, That's AWSOME, very clean inside. Are able to pinpoint a specific schem................

For me, the STINGER is the need to know, as I tried it and it didn't work very well. Thanks


This particular amp is: http://el34world.com/charts/Schematics/files/garnet/garnet_lb190d_pro.pdf (http://el34world.com/charts/Schematics/files/garnet/garnet_lb190d_pro.pdf)


The stinger is crazy!  Basically a herzogish type thang in front of the el34 amp. Hmmm :think1:



Title: Re: On the bench: Garnet Pro
Post by: jjasilli on April 11, 2014, 11:05:47 pm
 :thumbsup: ... and speaking of the "devil", Garnet is a hot topic of late!


(Not to mention I'm feeling vindicated, having advocated a preamp pentode as a "Herzog substitute" in a nearby thread)   :occasion14:
Title: Re: On the bench: Garnet Pro
Post by: HotBluePlates on April 11, 2014, 11:55:36 pm
That's very tidy for a true point-to-point amp! And the old school knobs are awesome! (Someone building their own tube studio equipment will probably try to steal them eventually)
Title: Re: On the bench: Garnet Pro
Post by: TIMBO on April 12, 2014, 12:31:03 am
Thanks  :icon_biggrin:
Title: Re: On the bench: Garnet Pro and Reverb Amp's
Post by: TubeGeek on April 12, 2014, 01:20:18 am
While I am at it, here are some pics of the other garnet I have for service.


This is a Reverb model.


http://el34world.com/charts/Schematics/files/garnet/garnet_lb100tr_rebel_reverb.pdf (http://el34world.com/charts/Schematics/files/garnet/garnet_lb100tr_rebel_reverb.pdf)
Title: Re: On the bench: Garnet Pro and Reverb Amp's
Post by: TIMBO on April 12, 2014, 03:25:24 am
NICE  :icon_biggrin:
Title: Re: On the bench: Garnet Pro and Reverb Amp's
Post by: John on April 12, 2014, 07:18:13 am
Cool stuff! Do you notice much in the way of hum? I ask because this amp, like some other of the older ones I've seen pictures of, doesn't pay much attention to twisting of heater wires. At first glance they do seem to run at 90s to the other wires though.
Title: Re: On the bench: Garnet Pro
Post by: SILVERGUN on April 12, 2014, 09:43:41 am
(Not to mention I'm feeling vindicated, having advocated a preamp pentode as a "Herzog substitute" in a nearby thread)
I believed in you all the way jj......it's just a time constraint thing for me right now...
Time seems to be the only thing I cant build right now....spring has sprung, and so has the honey-do list  :cry:

Great pics TG!....It's cool to see you get the hands-on with this stuff before you decide what you're gonna build....
It would've been pretty hard to get your hands on 2 Dumbles  :icon_biggrin:
Title: Re: On the bench: Garnet Pro and Reverb Amp's
Post by: SILVERGUN on April 12, 2014, 10:06:08 am
I'm having trouble wrapping my head around the dotted lines and circled X's in the preamp schematic... :w2:

Title: Re: On the bench: Garnet Pro and Reverb Amp's
Post by: TIMBO on April 12, 2014, 04:18:09 pm
Hey SG, I also may revisit a Garnet build, as both of the builds were bits and pieces of stuff I had.

Each of sound foundation pots have a pull sw. (X in circle)that adds/bypasses components and turns a neon on/off. The ones under the pots. Thanks 
Title: Re: On the bench: Garnet Pro and Reverb Amp's
Post by: SILVERGUN on April 12, 2014, 05:11:37 pm
Each of sound foundation pots have a pull sw. (X in circle)that adds/bypasses components and turns a neon on/off. The ones under the pots.
Thank you TIMBO,,,now I'm starting to see it
The dotted lines coming off of the pots just represent the switch function.... that's better

When I first looked at it, I was just :huh: :w2: :think1:
Title: Re: On the bench: Garnet Pro
Post by: jjasilli on April 12, 2014, 05:28:21 pm
(Not to mention I'm feeling vindicated, having advocated a preamp pentode as a "Herzog substitute" in a nearby thread)
I believed in you all the way jj......it's just a time constraint thing for me right now...


Thanks for your support!!  :icon_biggrin:   BTW: Merlin has info on this.  There's so many Garnet threads blooming this Spring, I don't know where to put this!  Anyway at the tail end of Ch3. Small Signal Pentodes, in Merlin's Preamp book, he mentions the use of pentodes in the preamp "so as to capture some of the traditional power amp distortion".  This might also include power pentodes; but is imperfect due to the the lack of an OT and actual speaker. 
Title: Re: On the bench: Garnet Pro
Post by: SILVERGUN on April 12, 2014, 05:48:15 pm
Thanks for your support!!  :icon_biggrin:   BTW: Merlin has info on this.  There's so many Garnet threads blooming this Spring, I don't know where to put this!  Anyway at the tail end of Ch3. Small Signal Pentodes, in Merlin's Preamp book, he mentions the use of pentodes in the preamp "so as to capture some of the traditional power amp distortion".  This might also include power pentodes; but is imperfect due to the the lack of an OT and actual speaker.
Yeah...I think WE are all onto something here,,,and I don't think it's limited to heavy or hard rock..
I'd like to hear a 5E3 pushing a 5E3, just as much as I'd like to hear a Herzog or a Stinger pushing anything.
And then the pentode idea just adds more options.....I see a lot that can be done and I'm already looking at a little toroid PT to build some kind of standalone something..... :dontknow:

I'm gonna wait to see what TG's thoughts are, and if there's anything to that stinger circuit......in the meantime I'm gonna read that Merlin....THANKS!
Title: Re: On the bench: Garnet Pro and Reverb Amp's
Post by: TubeGeek on April 12, 2014, 10:49:58 pm
Cool stuff! Do you notice much in the way of hum? I ask because this amp, like some other of the older ones I've seen pictures of, doesn't pay much attention to twisting of heater wires. At first glance they do seem to run at 90s to the other wires though.

No hum at all.  Quiet as a mouse.

I'll try to make a recording of these so you can hear what I'm hearing.
Title: Re: On the bench: Garnet Pro and Reverb Amp's
Post by: TIMBO on April 13, 2014, 03:02:23 am
COOL
Title: Re: On the bench: Garnet Pro and Reverb Amp's
Post by: John on April 13, 2014, 05:57:13 am
Cool stuff! Do you notice much in the way of hum? I ask because this amp, like some other of the older ones I've seen pictures of, doesn't pay much attention to twisting of heater wires. At first glance they do seem to run at 90s to the other wires though.

No hum at all.  Quiet as a mouse.

I'll try to make a recording of these so you can hear what I'm hearing.


Cool beans, thanks!