Recent Posts

Pages: [1] 2 3 4 ... 10
Q & A / Re: My model T does not match the schematics
« Last post by EdBass on June 21, 2022, 12:29:40 pm »
Some of the Sunn mega rigs of the late 60's/early 70's were similarly modified. I think someone posted pics of Pappalardi's Sunn rig with ins and outs here, but I can't find it.

A few years ago I had some conversation with Steven O'Malley from the band Sunn 0))). The emails are on a now defunct PC's hard drive, but I'm pretty sure he told me that he played 9 Model T's on stage simultaneously. I guess theoretically he could have daisy chained inputs, but I think it would be more likely that he had them rewired as the amp we're discussing here. Sunn

liwerks2; You got the rig from the original owner, right? Ask what and why they did the mods, that should settle it.
Q & A / Re: My model T does not match the schematics
« Last post by Isaac on June 21, 2022, 09:23:44 am »
Interesting. I've never seen anything like that on a Model T. I'd like to see how it's worked into the circuit.

Aside: a bandmate had a Fender tube amp with pre out and power in, but that was implemented via some solid state circuitry.

This is what I expect the rear panel on a Model T to look like, though mine is a 2G:
Q & A / Re: My model T does not match the schematics
« Last post by liwerks2 on June 20, 2022, 10:29:55 am »
Alrightly! I did not understand how attachments work on this website, so here I try again to attach photos (my wife also thinks I can be trained, but the supporting evidence is minimal). Here is another photo of the back side of this amp with the in/out jacks in question. The amp (as I purchased it) had the typewritten labels on it that you can see in the photos. The writing in Sharpie was me ensuring that I could find the right jacks (for the speakers, etc.) in the near dark, which was consistent with the bars and cow barns that I played at in the 1970's.
The line out jack is certainly there, and that is consistent with the first gen schematics that I have, but there is also the input/output jacks near the speaker jacks.
I obtained this beastie used in the mid 1970's, so it could be an early prototype/production model, but I have no way of telling.

Now that I am in my late 60's, and between BMI/ASCAP and Covid19, there are no longer places for local bands to play, therefore I am prepping this amp for sale (along with 5 cabs and 5 other tube amps) and I want my description for Ebay to be accurate. (For some obscure reason my wife does not think big Sunn amps are suitable decorations for our living room. I disagree......if she is out of earshot.)

Later today I will modify my Model T 1st Gen schematics to include these jacks.
Q & A / Re: Sunn Tone Stack
« Last post by Isaac on June 19, 2022, 11:21:08 am »
No, definitely not what was used on the 200S or 2000S, but similar to what was used in the 2G Model T.
Q & A / Re: My model T does not match the schematics
« Last post by Isaac on June 19, 2022, 11:16:11 am »
As far as I know, the Model T has always had a line out, and never had a line in. I don't see a line in in your photo, either. In most amps that have one, the line out comes after the preamp but before the power amp. In the case of the Model T, the line out comes after the power amp. It's just a couple of resistors to reduce the output voltage to a line level. You can make an external one for older amps that lack it.

I wonder if yours is an early production model. It doesn't have the finishing touches I would expect on an actual production unit. Labels written in Sharpie? Doesn't sound ready for prime time to me. Either the labels came off, or were never put on. Maybe a late prototype? Or maybe they just came off.
Q & A / Re: Sunn Tone Stack
« Last post by liwerks2 on June 18, 2022, 06:20:21 pm »
I have attached a pdf of the PJ Baxandall white paper on tone stacks. It's not exactly what is being used here, but has good information for curious tech weenies.
Q & A / My model T does not match the schematics
« Last post by liwerks2 on June 18, 2022, 05:52:00 pm »
Good day, all:
    I have a Model T that I purchased from our guitarist back in the mid-1970's (one owner). I am under the impression that it is a early production model, and I am re-capping and re-tubing this beastie prior to possibly selling it (I am way too old for stage any more, and it's just tooo loud for use at home.
    My question revolves around that fact it does appear to be an early production model, but it has what appear to have line in, and a line out jacks on the back, and these do not appear in the schematics that I have. The inspection label appears to be dated as 9-23-71 or 9-23-74 (1974 seems more likely). To this point, I have not found a listing of serial numbers that would enable me to pinpoint the date any closer, although the SN plate #48847. I have included photos with this posting and would appreciate any illumination concerning exactly what do I currently have on my bench.
    I can provide more photos if someone would benefit from circuit details, etc.

    Thank you for your time and consideration. -L
Q & A / Re: 118MH cabinet restoration
« Last post by strategypaul on June 16, 2022, 02:56:12 pm »
Thanks, this is really helpful!!! I think that restoring the tolex, corners, casters, and feet are probably all things I can do myself, TBD
Q & A / Re: 118MH cabinet restoration
« Last post by Isaac on June 16, 2022, 08:58:53 am »
The cabinets were covered with Tolex, and had metal corners. The visible horn surfaces were painted flat black. In addition, they had fairly large rubber feet on the bottom, and removable casters on the back.
Q & A / Sunn Beta Lead potentiometer question (edited)
« Last post by sonichris on June 16, 2022, 07:42:16 am »
I have a beta lead with a broken treble pot (the knob broke off). I checked the schematic and it's a a 100k linear pot. Having a hard time finding a replacement, anyone know of a supplier? It's a 4 leg pot, 4th leg is just for support on the board. I have read that these have been replaced with a 3 terminal pot wired to the board when an exact replacement couldn't be found but would prefer to replace with original style.

(edited, found correct info, it's a 100k linear pot)
Pages: [1] 2 3 4 ... 10