Great sounds, your best yet!
Sounds like the amp has a nice compression on the OD. How does it feel playing wise.....can you get thos tones with low volume or do you have to crank it? looks like you've got the volume at noon.
What is your gain trim setting? (measured from center pin to ground)

You need a special Dumble drill 

Well, sorry to hear that. Sounds like your 2290 could have a faulty OPamp somewhere.

If you ran the system in parallel, you surely would have less trouble. Some people with similar machine park as yours, use a Shur minimix II and report having fine results (like Dogears aka Scott Lerner).

Maybe, you are overdriveing the input of the 2290 with too much signal from the loop-a-lator. Try reducing the drive.

Ok, so the snubbers was the problem ?

You can easily run the amp without snubbers, although it will be pretty harsh in OD mode.

5uf/180k ?

you need 5uf/2.2k

 Pin6 & 8 are way out of range....so your problem is V2b

half on a 50k pot


Yes, you can and a simple alpha 50kB pot will do. It'll set you back 1 Euro.

Check the power supply to V2, is it broken of somewhere?

I have a #124 50w clone with Winged C 6L6 and an Skyliner HRM 50w with EL34B.

The EL34B's are like driving a big nice Mercedes as compared to a WV Golf.

Bigger low end on the EL34B's - like a 100w with 6L6.
Middle is less pronounced, which is great for an ODS.
Top end is nicely laid back and never brittle like 6L6 can be.

I've tried a lot of 6L6 tubes/valves in my #124 clone (GE 6L6, Sowtek 5881, TUngsol 6L6 among others) and so far the Winged C's are the closest to EL34B.

Check the wires to/from the OD relay.

Like Steven said it simple two (schielded) wires and a pot.

Tip: Instead of a 100k pot, I use a 50 pot with a 50k fixed resistor 'on top'........like most of you I never put the trimmer above 12 o'clock/50k................. so this way my pot works in a more approiate range 0-50k. And 12o'clock is approximately 25k, which is where I tend to prefer the trim/pot.

Here's a little something to get you even more hyped :-D
........................................

http://www.quinnamp.com/sdodescription.htm

Dumble amp types

Vintage is one of the older types of this style of amp. A bit more rooted in the raw Fenderish tone. This is the amp that established the legend. It can sustain like a mofo! It is a singing OD for sure. Not much compression, very touch sensitive and dynamic....

Skyliner I (low plates) (#124) is a variation of the above.  A new tone stack is used. It is a little less Fender but still a somewhat lower gain affair. That is to say it is very touch sensitive and it requires a dynamic hand to control the amp. Most people like to set the gain low and push the power amp, rather than cranking the gain and trying to dynamically reel it in. Either approach will work but I think this amp likes the pushing more than the reeling back. It has the same gain as the vintage amp but the new EQ is more "signature Dumble" and a little less Fender. Improved cleans from the Vintage model. It still sustains like a mofo, has a bit better string to string definition and is a little more refined in the tone shaping.

Ceriaton OTS = Skyliner II (High Plates) has more headroom, definition, and punch, more lively and responsive clean sound, smoother OD, and a small bit of compression, very touch sensitive, with lots of sweet singing tones.

HRM Skyliner II contains a second tone stack just for the OD channel. It is more or less a Marshall style tone stack this allows tone shaping of the OD independent of the cleans.  Smooth as silk, goes from clean to mean and transition between the two is amazing. You can pick clean, a bit dirty, grinding, soaring, all with your hand and all smoothly with definition. No rasp or buzz. Very refined sound with gorgeous smooth tones. A little more compression that the above amps but not in a bad way. Very natural with a dynamic response, that is second to none. This amp feels like it breathes with you after awhile.
Smooth singing overdrive, completely dynamic, never any rasp or buzz, no IM distortion or other uglyties. This is so far the most requested one and the amp I could not be without. It's smooth but never bland.

Bluesmaster Think raw early Fender/Marshall tone on steroids. The tone stack is decidedly Bassman territory, however because of its Dumble genes, and many other differences, it is far better. The clean is the best cleans I think I have ever heard, in a Dumble or otherwise. The clean sound will sing and sustain!!! The OD is much less smooth and much less compressed than the above amps. It has some early Marshall vibe to it. Boosted cleans with this amp are to die for. The OD is a bit more raw and edgy then some of the other offerings but with boosted cleans you get the smooth side of things and with the OD you have a less polite and refined tone. Lots of punch, sustain and singing but not as smooth as some of the other offerings. This one can be thick and dense too. Not dark and crappy, just "meaty"...Open clean cleans to mean and a little rude.  It is a big, fat, blues machine with lots of character or soul, which can play nice but still stomp in the dirt. It has a HRM post OD tone stack which gives a little more tone shaping and refining in the OD section.

Its true that a Dumbleator puts the signal out of phase, but so is a Fender Super reverb. I don't think the phase topic is what makes the difference in sound. I believe its the fact that you put some ekstra cable and thereby capacitance into the circuit.

I run my dumblelator in parallel mode, whereby I have a minimum of extra cable, but in order to get the high end roll off that you get in 'normal' serial mode, I just add a cap here and there to get the same effect.

I've moved the trimmers to post on the bottom of the chassis. What I found is the once you get the trimmers dialed in (especially the bass trim) you dont want to touch them. In fact I'm going to move back to trimmers, set to the same current setting as the pots.

I found the setting the trims/pots so sound as closely to a NON HRM as possible is the deal. On my amp the bass pot is barely on, its at the beginning of where you can hear the bass coming on. The mid is around 11 o'clock and the treble is around noon.

If you like the sound of your amp as is, Don't mess with the trimmers, or at least make a pencil mark on the trimmers to to indicate the current settings, before you start dialing them.

I agree with