strange mod ... and lot of questions !!!

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j0k3335
Posts: 138
Joined: Sun Sep 23, 2007 5:09 pm
Location: Paris, FRANCE

strange mod ... and lot of questions !!!

Post by j0k3335 »

I do not like the PAB of my Ceriatone Bluesmaster 50W: too much gain suddenly and a ton of medium! Also I want to remove it (and get the relay): how to remove it?
Connect VR2 from the middle potentiometer to ground OR through a resistor or ...
Help me :D

BUT I understood that the two tone stack for the OD was not ideal!

Also I would like to bypass the tone stack stage with a circuit that would be equivalent and adapted in impedance. The values I mentioned are probably far-fetched! I was inspired by a post from? Ontarius? (whoever makes the PHAEZ amps : I bought one, but it was not a model for me, but the construction was really exceptional !!! Real point to point, and really TOP level ! )

What do you think of this idea ? ridiculous or could it work ? What could be the circuit to make and values to choose ???

And this is the reason I need the PAB relay. ... But I understand nothing about the way they show how they connect these relay ON LAYOUT ! On a schematic, I can understand what is a Normally open or normally close position , but here HOW I have to wire my mod to this , now, free PAB relay ??? ( only a small layout could help me :) )

Image

A great thanks for some help for this mod IF it is POSSIBLE or another solution/idea ?

2 last questions :

1°) again my midboost is "too much" for me : too much medium : changing the cap (390p) value could be enough ? What kind of value ? ( ceramic ) ?

2°) caused by Health problem ( yes already at 65 years old :cry: , I will have to play now, ONLY ... at home : so what could be your advices to get the best of this 50W in such
situation . I remember to have had a 15W position on my Fender 75 ( 75W) only by changing B+ and bias with a switch : could it be a good idea here OR do I have to absolutely keep this
special Bluesmaster PI and power section the cleaner possible ?

Other ideas, advices ?

Thanks for your help.

PS : there are TWO possibilities : one with the full relay, the other only with one side ( I could use this side for some tweaking on the OD, ... ) BUT with the "one side" solution, will I get hum, HF noise, ... ?

PS2: ... you have understand that English is not my mother language : so, I'm so sorry for this odd writing :oops:
Last edited by j0k3335 on Sat Dec 02, 2017 12:30 pm, edited 1 time in total.
mojotom
Posts: 237
Joined: Wed Feb 01, 2006 12:47 am

Re: strange mod ... and lot of questions !!!

Post by mojotom »

I don't know if this could to be helpful but the PAB on the bluesmaster (or so called Megaboost lifting the tone stack by 22M, a huge boost) is supposed to be activated at the same time as the OD, bypassing the tonestack leaving only the HRM tonestack at the end of the OD.
It will sound huge on clean for sure, you could try a lower resistor value (50-200k) if you want a boost for the clean.

I would try to wire the OD and 22M lift to be activated by the same footswitch, for OD, and wire another relay with a milder boost for the clean.


Aucun problème avec ton anglais ;)
j0k3335
Posts: 138
Joined: Sun Sep 23, 2007 5:09 pm
Location: Paris, FRANCE

Re: strange mod ... and lot of questions !!!

Post by j0k3335 »

mojotom wrote: Fri Dec 01, 2017 11:18 pm I don't know if this could to be helpful but the PAB on the bluesmaster (or so called Megaboost lifting the tone stack by 22M, a huge boost) is supposed to be activated at the same time as the OD, bypassing the tonestack leaving only the HRM tonestack at the end of the OD.
It will sound huge on clean for sure, you could try a lower resistor value (50-200k) if you want a boost for the clean.

I would try to wire the OD and 22M lift to be activated by the same footswitch, for OD, and wire another relay with a milder boost for the clean.


Aucun problème avec ton anglais ;)
"Aucun problème avec ton anglais ;)" : thanks ( but you kidding :D )

Thanks for these solutions.

Probably I don't explain myself correctly : I DON'T NEED/WANT BOOST nor in clean or OD. But, as the Bluesmaster is HRM, I have ANYWAY to do something to avoid to have the TWO tone stack
in OD mode which is not ideal .
It's the only reason of my idea for this mod.

... and ... next, AS my HRM could be bypassed by a switch ( Ceriatone mod) ... I will have to deal with mods to get this "normal" OD sounds as a ... "usual DUMBLE OD" ! ( which is not the case now, probably because of the Bluesmaster preamp specially with 100K/1K5 on both side of V1 !? ... and this is why I would like to keep a side of the PAB relay for, in this case, a snubber, a filter, ... ).

In the meantime, If I don't find a solution, your idea of wiring the OD and 22M to be active in the same time is an elegant solution :wink:
mojotom
Posts: 237
Joined: Wed Feb 01, 2006 12:47 am

Re: strange mod ... and lot of questions !!!

Post by mojotom »

I didn't build a Bluesmaster yet but like I said you need to remove the first tonestack to run the OD. Considering the tonestack is passive it will load the signal down. When you will remove it from the signal path you will have a huge boost.
You need it for the OD, it is design that way, boost+OD=OD or you will have 2 tonestack in the signal path.
There is more to it as the entry of the OD on this amp (with its OD trim) is design to handle the hot signal of the boosted clean. Once in OD+boost you could bypass the second tonestack at the end of the OD for more gain (if it doesn't make too much noise or oscillations, I didn't try it).

You will have hard time just removing the second tonestack for a non-HRM OD as the whole clean+OD preamp is way different than a classic Dumble ODS (skyliner for example). You should try and see what you think about it.

Send me a pm if you need some more help.
j0k3335
Posts: 138
Joined: Sun Sep 23, 2007 5:09 pm
Location: Paris, FRANCE

Re: strange mod ... and lot of questions !!!

Post by j0k3335 »

mojotom wrote: Sat Dec 02, 2017 1:04 am I didn't build a Bluesmaster yet but like I said you need to remove the first tonestack to run the OD. Considering the tonestack is passive it will load the signal down. When you will remove it from the signal path you will have a huge boost.
You need it for the OD, it is design that way, boost+OD=OD or you will have 2 tonestack in the signal path.
this is why I try to design an equivalent circuit WITHOUT boost ( and those HUGE medium ! ) that I will swap WHEN going to OD mode.
mojotom wrote: Sat Dec 02, 2017 1:04 am There is more to it as the entry of the OD on this amp (with its OD trim) is design to handle the hot signal of the boosted clean. Once in OD+boost you could bypass the second tonestack at the end of the OD for more gain (if it doesn't make too much noise or oscillations, I didn't try it).

You will have hard time just removing the second tonestack for a non-HRM OD as the whole clean+OD preamp is way different than a classic Dumble ODS (skyliner for example). You should try and see what you think about it.
Nik from Ceriatone had already installed a switch to bypass the HRM tone stack : it seems that he installed a 0.002 cap and a 4M7 resistor to ground ( sorry the layout is not really clear : lot of comments ! )

Image

Except a little bit a volume jump that works ... but I'm a little bit far from the "classic Dumble OD" ! ... But it will be a second stage of mods : let solve first this idea of a circuit without boost and medium replacing the PAB !

THANKS for all your explanations and suggestions :wink:
j0k3335
Posts: 138
Joined: Sun Sep 23, 2007 5:09 pm
Location: Paris, FRANCE

Re: strange mod ... and lot of questions !!!

Post by j0k3335 »

If this OD really need to have the first tone stack swapped ( I understand this !), at least is there a way to "moderate" this too huge boost ( playing with the 22M resistor ? plus, minus, ) !

And how can I "lower", in this case, the middle : really too much !!! ( some kind of filter ? associate with the PAB ? )

Thanks for some help, some ideas :wink:
mojotom
Posts: 237
Joined: Wed Feb 01, 2006 12:47 am

Re: strange mod ... and lot of questions !!!

Post by mojotom »

Well the more resistance you use between the TS and ground the more lift you get.

Full boost if you keep the connection from mid pot to gnd open
22M should be a bit less but huge boost too.

Anything lower than that will give you less boost, I use around 70-80k for a mild boost on the clean.

Put the biggest trim you could find, you'll have a variable boost.
10thTx
Posts: 1863
Joined: Sat Dec 30, 2006 1:13 am

Re: strange mod ... and lot of questions !!!

Post by 10thTx »

On one of my D-inspired amps, instead of .002 (mid-boost) with 390p ............. I use a .00125 and a 540p for a milder mid boost when boosted. You could use a .00125 and 390p if you wanted.

Instead of the 22M on the PAB, I use a 4.7M and that works to my liking.

with respect, 10thtx
j0k3335
Posts: 138
Joined: Sun Sep 23, 2007 5:09 pm
Location: Paris, FRANCE

Re: strange mod ... and lot of questions !!!

Post by j0k3335 »

to mojotom and 10thTx,

Thanks guys for your advices ... and your patience (understand that I'm a little electronic but concerning amps , it was limited to Fender.So there, I am in another world and a little lost! :? )

as soon as I get out of my health problems:

. I will dismount this head, ( and I will improve the values of the layout and drawn a cleaner one for better explanations )

. and I will test your different recommendations!

obviously, I will keep you informed :wink:
Thanks again,

José
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