Thanks people for your responses. It is clear to me now.

I never really dived into the whole tremolo thing as I am not a big fan of the tremolo sound in genereal and I just noticed the entirely different circuitry.
So I'll just take your words for it that the way Nik did it is the best sounding way

I apologise for not following the 'rules' regarding the posting of pics, but what I meant in my first reply is that if one needs pictures to see the difference between the two, he probably wouldn't have known the answer to my question 

Anyway, thanks guys!

I could post pics, but I assume that people understand what I am talking about if I say that Nik's tremolo layout is nothing like the original??

Hi,

I searched around but found no discussions about this subject.
I am building a bluesbreaker amp and while doing this I noticed that Nik's layout and circuit is very different from the original BB circuit? There's no FET and so the overall circuitry must be different.
I don't have any technical info about the original but from the pictures I have I can see a lot of differences.

Anyone has any info?

Ah! Good catch. Hadn't noticed the fact that there's  2 heatercircuits.

That explains it

HI,

I am about to build a DR103 clone. Going by pics and layout of the original but using some of Nik's parts.

First thing that catched my attention is the heatersupply. Why is Nik adding 100R resistors to ground (normally used with a tranny without center tap) while the tranny cleaarly has a center tap?

Just wondering

Okay, but that only works on the clean channel, so how will that help the OD channel?

Hi,

Does anyone know why the internal HRM tonestack Bass trimmer value was changed from 1M to 220k by Nik?
My favorite setting was 230k for the bass and now that would be the max value for this pot?

Was this changed by popular demand or something?

Hi, we might try this mod to see if it helps in this amp. Do you mean the 'Level' pot?

To be honest, I am starting to get the feeling there is nothing wrong and that it's our ears playing tricks somehow...

I just had both amps hooked up to a stereo cab with 2 G12-65s and I used an A/B box to be able to switch between both amps. Had the exact same settings on all knobs and started turning the tone knobs.
At first I thought I heard a difference in response of both Mid knobs but after playing for a while, I wasn't so sure anymore...

Exactly, I am talking about a discrete resistor on the board. Connected to the plate of the first triode, a 100n going yo the Bass control and a 10n going to the Mid control...

Really? You're not kidding? The Ceriatone layout says 150k....
I'm gonna try that as a last resort, but wouldn't it influence the Bass to much?

Thanks all for your insights.

I agree that the range of the tone controls is limited in general, but the fact remains that I have 2 amps, built the same way and one of them is barely reacting to the MID control.

Which is odd, because the MID is the most straight forward of them all. It's a plate signal going through 150k and a 10n cap...  what could go wrong???
So it is still puzzling me why I can barely hear a difference when I am turning the MID control on one amp and a clear difference when doing it on the other (with all other settings the same, treble and bass at about 12 o'clock).

There must be something I am overlooking....

I got something similar for the HRM 50, but.... 37Volts on pin 1 & 8 ?? 37Ampere current trough those cathoderesistors?

And av. 240V on the plates of the PI seems a bit high too....

I have also downloaded the software to try and simulate what I am doing (and to understand )

But for some reason I now realise I can't get my head around how the HRM's extra piece of tonestacktrimmers incorporate into the 'standard' tone stack...

EDIT: Okay, I got my head around it I realise the HRM trim tonestack is really a standard Marshall tonestack, behind V2.
If I increase the slope resistor, the entire curve drops and the dip gets even deeper... How will this help make the front Mid control more effective?

Thanks for the suggestions!

Both pots are 250kA as per layout and even their actual values are close enough....

I will sure try the pot instead of the slope resistor to see what that brings me.