The REAL DEAL Dumble Shootout!

[briane]

great work funk!

this is exactly the kind of info we need!

I will ask, but dont feel obliged to answer...I know you have a number of personal mods you tweak to taste, but aside from that is there a schematic you might direct us to that embodies the basic 'spirit' of your build?

[Funkalicousgroove]

This one is basically the 1997 circuit from the files section with the Phase inverter section from a Marshall JCM800 2204 (Also found in more recent dumbles.)

[les_guitar]

How to you think the third Dumble would compare with my 100 watt HRM Bludotone?

[heisthl]

This one is basically the 1997 circuit from the files section with the Phase inverter section from a Marshall JCM800 2204 (Also found in more recent dumbles.)

The 2204 uses a 5k presence pot and a .022 to couple the NFB back to the PI - do you like those values or do you prefer the 25k pot with the .1 coupler?

[Robert]

What a great story Funk. Thanks for sharing it with us!!

Robert

[novosibir]

Last night I was invited over to a fellow's house who just happens to own not one, not two, but THREE Mid/late 80's 100W Overdrive Specials.

Back in 1997 - 10 years ago now - I've had the same fortunate circumstances at Siggi Schwarz Music in Heidenheim/Germany.

He also had 3 Dumble ODS at the same time in his shop, each sounded different to the other, but all three sounded great. The in my ears best sounding out of this 3 amps was supplied with the Schumacher 135W irons - and of course w/o a choke, since the power stage is ultralinear.

The HRM had an OT that I didn't recognize, but it could have been another MM, it had the brackets like the MM OT's but this one was REALLY thick-maybe a 150W MM?

That maybe was also 135W irons in this amp, the OT is about 1/4" thicker than a usual Twin OT - and the PT is huge in its height.

Larry

[dobbhill]

A Dumble ODS with ultralinear output? Please tell me more!!
D

[novosibir]

A Dumble ODS with ultralinear output? Please tell me more!!

To be honest - I haven't digged deeper into this Dumble, because Siggi hasn't admitted to open it. But it definitely had no choke, it had the thicker OT like the 135W Fenders do have with the additional 'striped' cables for the screen taps going into the chassis, and IIRC it also had this huge PT. But on that with the PT I already wouldn't swear an oath, because it's already too long ago!

Anyway, after that I've build some Dumble clones at that time, but based on Fender DualShowman 135W models inside with a completely new designed fiber eyelet board. The left side became a Blackface Clean and the right side the Dumble OD (Speed & Intensity became Overdrive & Level), both channels went into Reverb and a parallel effects loop. The 7-th tube got the place of the Reverb tranny, the reverb tranny went on top of the dog's house.

I've build it after 70' specs with 100K plate and 1.5K/4.7µ cathode throughout, but with the HRM after the OD section.

Here you can listen to some clips, recorded with one of those 135W Dumble clones, fitted w/ NOS 7581A's:

http://www.larry-amplification.de/dclon ... esobad.mp3
http://www.larry-amplification.de/dclon ... d-over.mp3
http://www.larry-amplification.de/dclon ... -revel.mp3
http://www.larry-amplification.de/dclon ... d-seed.mp3
http://www.larry-amplification.de/dclon ... street.mp3
http://www.larry-amplification.de/dclon ... spring.mp3
http://www.larry-amplification.de/dclon ... ygbtea.mp3

Shure, the amp's sound isn't comparable to the clips, I've heared here on this board - but anyway, enjoy it!

Larry

[Funkalicousgroove]

I use the .1 and the 25K.

Les, I'd say your amp is a tad more aggressive sounding than the Dumble, but quite a bit sweeter sounding than the one I brought with me.

I think your amp would have actually been a bit closer to the Real one.

[v-verb]

How about my 2 Brandon?

Cheers

Nigel