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Hoffman Amps Forum image Author Topic: My D'MARS ODS 5879 finally has a home...  (Read 4636 times)

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Offline MakerDP

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My D'MARS ODS 5879 finally has a home...
« on: March 20, 2019, 10:03:21 pm »
OK so after two or three years... I finally built a head cabinet for this amp.

Pics aren't great but you can see the gist of it. Flash is obnoxious but it was the only way on my phone I could figure out how to show the figured maple on the front panel.

Obviously the theme I was going for was "Beat-up Army Crate."  :laugh: The head and speaker cab are done in camo green with clear spray-on truck bed liner. The speaker "cloth" is plastic window screen spray painted the camo green with the white star sprayed on in white. The sides of the speaker cab have the same large white star as the front. These  cabs are (speaker) and will be (head) heavily gig'ed so they are finished so that dents-n-dings are like "oh well" as far as I am concerned. I don't go trying to ding them up but hey - the backs of pickups and helpers - you know...

One thing I need to fix is the gap between the front panel and the chassis and there is no handle yet... this was all built with what I had on-hand in the scrap pile but I don't have a spare handle.... will have to order that.

One pic shows the rivnuts I bought from Doug and you can see the cheap $22 tool I bought to install them in the thread in the tools section here.

The speaker cab is an Avatar that I bought as a knock-down pack and assembled myself when they were doing that. I have the feeling I was one of the only ones who bought one because they did not offer that option for long. Too bad... it's a nice way to go for sure! Speaker inside is my standard favorite WGS ET65.

I have one of those cnc vinyl cutters that teachers love to death and I will be using that to make a "faceplate" eventually.

Oh and the important thing... this amp sounds really, really nice.
« Last Edit: March 20, 2019, 10:07:57 pm by MakerDP »

Offline Slimtim

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Re: My D'MARS ODS 5879 finally has a home...
« Reply #1 on: March 20, 2019, 10:24:39 pm »
nice work.i really like that cab too.

Offline Papa Jim

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Re: My D'MARS ODS 5879 finally has a home...
« Reply #2 on: March 20, 2019, 11:27:40 pm »
I like the cabinet also, and your work on the amp. Kinda curious about the amp. I've seen a few things about it in the past but mainly it was concerning a 1 tube reverb if I remember correctly.

Offline tubenit

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Re: My D'MARS ODS 5879 finally has a home...
« Reply #3 on: March 21, 2019, 05:31:00 am »
Hey, that looks great!  Thanks for sharing it.  Glad you like the tone of the amp.  The ET-65 is a good speaker choice
for that amp.

With respect, Tubenit

Offline Papa Jim

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Re: My D'MARS ODS 5879 finally has a home...
« Reply #4 on: March 21, 2019, 07:31:06 am »
I'm limited technically but enjoy building. Looking for future project. Google always leads me to you MakerDP and Tubenit about this amp. Anyway without going over my head could I please get a link or brief explain of the D'Mars features, pros, cons, etc. I'm looking for another project for SRV style blues sound if that is even possible.

Offline tubenit

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Re: My D'MARS ODS 5879 finally has a home...
« Reply #5 on: March 21, 2019, 08:25:52 am »

I have quite a bit more info about this amp.  I did several versions of it with FX, no FX, with 5879 in OD, without 5879 in OD.
It's cathode biased with a 300-0-300 PT.  So, I've actually used 6K6 tubes with a 5Y3 rectifier.  I've used 6V6 tubes with 5Y3, 5V4, & GZ34 rectifier.  I've used 5881/6L6 tubes with 5V4, GZ34 and solid state rectifier plug-in. 

Some D'Mars ODS  sound clips of my amp:

https://www.soundclick.com/html5/v4/player.cfm?songID=11842172

https://www.soundclick.com/html5/v4/player.cfm?songID=11824794

DaGeezer built one also & his playing is waaaayyyy better then mine:
https://soundcloud.com/dageezer/dumars-noodles1-0

D'Mars (non-5879) with FX on board:  http://el34world.com/Forum/index.php?topic=15406.msg148467#msg148467

D'Mars with 5879 in OD:  http://el34world.com/Forum/index.php?topic=17305.msg173282#msg173282

with respect, Tubenit



Offline MakerDP

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Re: My D'MARS ODS 5879 finally has a home...
« Reply #6 on: March 21, 2019, 08:59:47 am »
Thanks guys.

This version is the 5879 with effects loop. I used solid-state rectifier but I am thinking of converting to tube... the socket is there and in fact the diodes are wired on the socket's terminals so it would be a very easy fix. I think I may have done a little tweaking with the 5879 component values and I experimented with different effects loop configs but ultimately went back to the original design on that. If someone wanted to simplify the build somewhat, I could probably live without the PAB as I have favorite pedals for that... that would eliminate a relay and a couple components and simplify the remote switch box.

I run tung sol reissue 5881 power tubes.

I will say, however, that this was by far the most complicated build I have ever done. It is my own layout as well. So, be honest with yourself on your build skills before you tackle this project. If you are diligent and pay attention to detail and have good lead-dress skills it should not be a problem though... just a long complicated build and as you can see LOTS of chassis drilling. I put it in a nice large chassis (I think it's 20x9x3) so I would have plenty of room inside and plenty of room on the faceplate for all the controls. I did have to put the presence knob on the rear... just couldn't squeeze it in there and make it look right with the staggered knobs.

Not sure it matches the "SRV" description though. What do you think Tubenit? One of your Tweed-ish designs might be better for that?

Offline MakerDP

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Re: My D'MARS ODS 5879 finally has a home...
« Reply #7 on: March 21, 2019, 09:02:05 am »
I should add that if you do decide to build this amp, Tubenit was extremely gracious and helpful during my long planning phase as well as during and after the build to sort out some tweaks.

Offline Papa Jim

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Re: My D'MARS ODS 5879 finally has a home...
« Reply #8 on: March 21, 2019, 10:40:17 am »

Not sure it matches the "SRV" description though. What do you think Tubenit? One of your Tweed-ish designs might be better for that?
This would be my 5th amp build. I have successfully built the AX84 PI, AX84 4-40, Fender Deluxe Reverb, and a 5F2 Princeton. I only have the Princeton at this point. Heck I may have had what I want now but at the time was not seeking it. I have heard that a Champ (close enough to my princeton) modded with the combo of 12AY7, and 5751 preamp together gave an SRV Tone. Have been thinking along those lines also.




Offline tubenit

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Re: My D'MARS ODS 5879 finally has a home...
« Reply #9 on: March 21, 2019, 10:53:23 am »
I don't think the D'Mars is a SRV tone amp.

SRV's Dumble amp (to the best of my knowledge) was 150W SSS amp and designed NOT to break up. Reportedly, SRV "attacked" the strings so hard that he requested Dumble make him an amp that stayed clean.

In contrast, my amp with 5881's is about 23w & I am probably playing it more like 10-12w volume.   :l2:

With respect, Tubenit

Offline Papa Jim

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Re: My D'MARS ODS 5879 finally has a home...
« Reply #10 on: March 21, 2019, 11:29:42 am »
Thanks a ton guys for taking your time to give me some info. I think I am gonna mod around on the little princeton for a while. If nothing else a good learning platform and it already basicly sounds great to my ears.
« Last Edit: March 21, 2019, 11:33:17 am by Papa Jim »

Offline MakerDP

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Re: My D'MARS ODS 5879 finally has a home...
« Reply #11 on: March 21, 2019, 12:11:17 pm »
I don't think the D'Mars is a SRV tone amp.

SRV's Dumble amp (to the best of my knowledge) was 150W SSS amp and designed NOT to break up. Reportedly, SRV "attacked" the strings so hard that he requested Dumble make him an amp that stayed clean.

In contrast, my amp with 5881's is about 23w & I am probably playing it more like 10-12w volume.   :l2:

With respect, Tubenit

Here's a good writeup on the history of SRV's amps. A lot of his tone that people are familiar with is from the Vibroverb and the Dumble SSS, which yes was made to be very clean. He also went through Super Reverbs and Bassman re-issues.
https://www.guitarworld.com/magazine/blues-power-depth-guide-amps-and-effect-pedals-stevie-ray-vaughan-s-arsenal

Offline MakerDP

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Re: My D'MARS ODS 5879 finally has a home...
« Reply #12 on: March 21, 2019, 12:13:11 pm »

Not sure it matches the "SRV" description though. What do you think Tubenit? One of your Tweed-ish designs might be better for that?
This would be my 5th amp build. I have successfully built the AX84 PI, AX84 4-40, Fender Deluxe Reverb, and a 5F2 Princeton. I only have the Princeton at this point. Heck I may have had what I want now but at the time was not seeking it. I have heard that a Champ (close enough to my princeton) modded with the combo of 12AY7, and 5751 preamp together gave an SRV Tone. Have been thinking along those lines also.

Oh you could handle this build then no problem. A Deluxe Reverb is no slouch of a build. The D'MARS would expose you to relays but that's not a big deal especially if you use Doug's very nicely-made relay PCBs.

 


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