seperate clean/OD masters

[llemtt]

...omissis...

Can you "Dumble-ize" a Fender amp to the point that it shares the Dumble philosophy and sound, or would it be a compromise? It's a compromise. The actual physical construction of the Fender limits what can be done. In fact, after the last Steel-String Singer mod I did to David Lindley's amps, he no longer uses the Fender Bassman I Dumbleized for him. He wanted this luscious transparency and response--like floating in white clouds--and I came up with special circuitry. I can use a Fender chassis, but you have to rip everything off of it, fill in all the holes, and re-drill it. <b>They're just a little bit too squashed. A distance of half a centimeter makes a big difference in the way something sounds.</b> It's a science involved with what's called circuit constants.

...omissis...

[mat]

turn your OD volume completely off, then master maxed and D-lator return maxed, then play -> in case you hear something coming out from the speaker you surely have a leakage

With the settings You adviced:
With d-lator switch in bypass position - no sound.
With d-lator switch in on position - faint high pitch guitar sound. Is that the leakage ?

Thanks for the article. Next build = bigger chassis . . .

[llemtt]

With d-lator switch in on position - faint high pitch guitar sound. Is that the leakage ?

Yes!

There are some good reasons HAD didn't put the D-Lator inside but in an external box...

Remove D-Lator, add coax and your debugging should be 90% done

If am not wrong I noticed also that OD plate resitors are two "small" (1/2 watts?) metal film, they aren't directly related to OD overall brightness but I don't like them very much anyway.

Teo

[Bob-I]

I see a 220k trim pot on the HRM treble, that should be 250k, the OD entrance pot is 22k that should be 25k.

[Bob-I]

Oh, and the RN65D resistors are correct on the plate load, same as HAD used and make a huge difference in the charactor of the highs.

[mat]

I see a 220k trim pot on the HRM treble, that should be 250k, the OD entrance pot is 22k that should be 25k.

You are correct. I did put 30k in front of the 220k trim. You are also right about the OD trim. I have just found a 25k trim but it measures 23k4, so I thought to left the 22k in.

Oh, and the RN65D resistors are correct on the plate load, same as HAD used and make a huge difference in the charactor of the highs.

Right again but I ran out of the Dales Those two resistors might be the most important of the amp Very difficult to get around here. Would be interesting to make a clip before and after those two resistors ...

[mat]

There are some good reasons HAD didn't put the D-Lator inside but in an external box...

Agreed

Remove D-Lator, add coax and your debugging should be 90% done

I did fire the amp today while hitting a chord and the sound was first thick and without harshness. Then it faided and became too trebly and spoingy again. Then I checked the preamp board with very bright flashlite and with soldering gun hitted all suspicious looking spots. One resistor was not soldered at all but only bended around the turret after firing it again it was all different amp

I did a one take quick clip with sm57 + similar cheap one and putted them on two tracks with backing track. The amp sounds on the clip much darker than it really is ? Next time I try to put the mic nearer to the center.

I was constantly listening the amp and few times tweaked the amps knobs just a little while playing (+ the guitars volume), so the playin is uber-boring but the amp is not any more

There is still some kind of hard'ness on the sound but I hope it will smoothen up when time goes by.

Here are the knob settings:

[img1218]http://www.pichotel.com/pic/16028B31e/140976.jpg[/img]

..and here is the clip:

http://media.putfile.com/hrmlator

I'll make a final report when the reverb is done (please look at the other thread of mine).

If am not wrong I noticed also that OD plate resitors are two "small" (1/2 watts?) metal film, they aren't directly related to OD overall brightness but I don't like them very much anyway.

They are 0.8w ones. Would love to put the proper ones in

Big thanks for Your help. I'll change the coax'es in near future.

I also can expect a Celestion Heritage G12-65 (reissue) after one month

cheers,

[hipbluescat]

Matt

The clip sound good. Pleasant tones !

Thank you for your detailed reply.

Concerning this issue

Quote:
Is the yellow wire running from the board located next to the transformer with the 56 k resistor links up to the bias point were the pair of 220k resistors join ?


Sorry, I don't quite get this one. The 220k's (not connected) get their bias voltage from two separate trimmers. Yellow wire was used. Btw. What picture are You referring to ?

First of all I am referring to the circuit diagram. If you look at the yellow line that comes from the small circuit board on the top left hand side. There are two 100uf capacitors in series. In the center starts the yellow line. Where should this be connected to ?

Can you also please send me a copy of the article that you got ?

Can anyone post a completed diagram by any chance ?

Where did you buy your transformers from ?

Which switches was llemtt referring to ?

What was the new brand and model that you are using now ?

Regards

[mat]

The clip sound good. Pleasant tones !

Thank You

Thank you for your detailed reply.

You are welcome

First of all I am referring to the circuit diagram. If you look at the yellow line that comes from the small circuit board on the top left hand side. There are two 100uf capacitors in series. In the center starts the yellow line. Where should this be connected to ?

Sorry, I'm not really sure where that connects..

Can you also please send me a copy of the article that you got ?

I didn't got an article, just the part that was posted.

Where did you buy your transformers from ?

Same place as the chassis.

Which switches was llemtt referring to ?

The d-lator bypass switch that I did put in.

What was the new brand and model that you are using now ?

Apem mini DPDT.

Will be back tweaking on monday
cheers,