Ceriatone Dumble

[Brad737]

Did you complete your tests yet?

Thanks,
Brad

[orca]

Hi,
I changed the OT of my Ceriatone to a Fender 018343; much better tone
and more usefull with different speaker cabinets.I also increased the
resistor between CL2 and the OD to 220k and the resistor in front of the
Ratio pot to 180k.Level pot changed to 100K A .The OD is smoother now
and the level difference to the Clean channel more moderate.
Wolfgang

[wbfree]

I want to run el34's in mine, is there anything I need to change to make that optimum. I am on a steep learning curve as I am not a tech but love all this. Stayed up 'til 2:00 last night reading everything and downloaded some electronic manuals to study, would like eventually to build my own amp. I am an old guy hope my brain can still hold information

[Pete]

Are your output tube sockets wired for 6L6 or EL34? Are the screen resistors 1K? These would be the basic points as well as range of bias adjustment.

I want to run el34's in mine, is there anything I need to change to make that optimum.

[jelle]

I want to run el34's in mine, is there anything I need to change to make that optimum. I am on a steep learning curve as I am not a tech but love all this. Stayed up 'til 2:00 last night reading everything and downloaded some electronic manuals to study, would like eventually to build my own amp. I am an old guy hope my brain can still hold information

The EL34 uses more heater current than the 6L6. I do not know the specs of the power transformer but be carefull not to go over these specs.

Jelle

[wbfree]

Thanks jelle
When I asked Nik he said it was okay awhile ago. What I wanted to know is are there any values in the circuit that would make these tubes better in terms of tone. I just tend to like el34's better than 6l6's. Sorry for my lack of knowledge but it gets better as I study this stuff. I have been an excavator all my life and this is new to me.
Burnie

[jelle]

I'd just run it with EL34's and listen to the amp. If there is anything you do not like, start tweaking based on what you hear. You can always ask here like "How can I tweak the amp to make it sound more....."

I like the EL34 in the amp as well.

Jelle

[aprilia1k]

Hi,
I changed the OT of my Ceriatone to a Fender 018343; much better tone
and more usefull with different speaker cabinets.I also increased the
resistor between CL2 and the OD to 220k and the resistor in front of the
Ratio pot to 180k.Level pot changed to 100K A .The OD is smoother now
and the level difference to the Clean channel more moderate.
Wolfgang

Orca - I finished my OTS (Nik's) kit a couple weeks back. So, when you say you replaced the "resistor in front of the ratio", I assume you mean the 150k coming off the plate of OD2 in to Ratio (only one I guess)? Ratio goes to the relay then and off to the Master then loop before going to PI grid... (the relays still confuse my deconstructing the layout/schem, so I verbalize it to make more sense). Then an audio taper 100k level pot replaces the 250k linear pot... did you get these last two from a thread here on T.A.G.? I know that Nik's layout differed from the popular 220k + 100k trim coming in to OD, but still learning about the differences and tweaks that work on the Overtone. I know that much of the ODS tweaks are for 100w circuits, so always wondering how they translate to the 50w ceriatone circuit. Anyway, thanks for the info on your ceriatone. I'll be posting my build with pics pretty soon - before I ugly it up too much with tweaks (once I start desoldering, I have trouble keeping things pretty!) LOL

Cheers,

Stephen

[ayan]

Orca - I finished my OTS (Nik's) kit a couple weeks back. So, when you say you replaced the "resistor in front of the ratio", I assume you mean the 150k coming off the plate of OD2 in to Ratio (only one I guess)? Ratio goes to the relay then and off to the Master then loop before going to PI grid... (the relays still confuse my deconstructing the layout/schem, so I verbalize it to make more sense). Then an audio taper 100k level pot replaces the 250k linear pot... did you get these last two from a thread here on T.A.G.? I know that Nik's layout differed from the popular 220k + 100k trim coming in to OD, but still learning about the differences and tweaks that work on the Overtone. I know that much of the ODS tweaks are for 100w circuits, so always wondering how they translate to the 50w ceriatone circuit. Anyway, thanks for the info on your ceriatone. I'll be posting my build with pics pretty soon - before I ugly it up too much with tweaks (once I start desoldering, I have trouble keeping things pretty!) LOL

Cheers,

Stephen

For what it's worth, the LEVEL control should be a 100K LINEAR pot, not audio, if you'd like for the amp to mirror what Dumble did in the most non-HRM amps. ODS 124, as reported by me a couple of years ago and documented with pictures, had a 250K (audio, as it were) pot in that position.

Cheers,

Gil

[orca]

Aprilia1K,
Ayan is right! the Level pot is 100k Lin. not Audio .
I changed the original 150k+ 100k Trim pot combination to a 220k+
100k Trim pot,also changing the trim pot to more precise 100k value.The one Nik used had 82k.If it is that low,You should add a resistor to have
100k going to ground.
I changed the 150k resistor going from the 0,005uF capacitor to "X"
to a 180K. It makes a smoother change from Clean to Overdrive.
Worth to install is a "Treble Bleed" ; it is just a 330k resistor and a
1n capacitor in series going from "X" to Ground.
Some people made a small extra board with a 500k Trim pot and a
capacitor. You can also use one of the extra holes on the back to
put in a 500k lin pot, so You can dial in how much Treble You want to
bleed.

[aprilia1k]

Aprilia1K,
... also changing the trim pot to more precise 100k value.The one Nik used had 82k.If it is that low,You should add a resistor to have
100k going to ground.
.....
Worth to install is a "Treble Bleed" ; it is just a 330k resistor and a
1n capacitor in series going from "X" to Ground.

Thanks Gil, Orca. Linear, got it. Yeah - I'm finding that the Ceriatone circuit seems to be mostly (perhaps completely, I have not done an atomic comparison) equal to this schematic labeled "1Z4", basically a mod'd #124 I guess. I got my kit in late Feb. and waited a few weeks, just staring and planning and reading. Anyway - I will go with the 220k, and Orca, same as you, the trimmer is low (around 85k) so will either get another or add the 15k. Orca, one other question - I have seen a few threads where people recommend running the trimmer at about 30k going to ground (think one was Gil actually) or maybe 40k. You crank it to the full 100k? Perhaps I am misunderstanding what you're saying there.

I have seen the treble bleed on at least one schemo (early 80's "Grail...) and sounds pretty cool to try - might make for versatility with guitars/pickups I imagine.

Without derailing, but I've been lurking awhile and need to jump in a bit now - anyway: "HRM" . I have seen what the acronym stands for but not really seen a descriptive on what it is. From a schemo I saw, it looks like separate CL/OD masters, a second tonestack for OD perhaps, and ? Or, am I way off? I've surfed a large number of threads and if this is detailed somewhere I missed it. Anyway - once again, fantastic forum and great people here. Cheers to the ODS circuits, and soul-stirring tone!

Stephen

[orca]

Stephen,
I mean measuring about 30k from the middle lug of the trim pot
to ground.The layout " 1Z4" comes close to the Ceriatone layout,
except the Ceriatone only has 2x 6L6 .
HRM is for "Hot Rubber Monkey" ;You are right it is a
added tone stack after OD2.
I found a layout called " ODS-101-" at
ampgarage.com/forum/download/file.php?id=1180
Wolfgang

[scotto]

Just FYI, my recently received Overtone came with the 220K resistor in front of the OD trimmer. Nik must be listening to your recomendations. This may also explain the difference in percieved harshness previously noted by Fullerplast and Dogear's friend CB. I found my OD trimmer set a bit too harsh for my taste. The re-trimmed amp sounds good through a combination of 12-65 and EV cabs. It's not in SLX territory yet, but I'm hoping that Scott can help me get it closer. I live nearby.

Scotto

[ic-racer]

schematic labeled "1Z4", basically a mod'd #124 I guess.
Stephen

Exactly. I built '1Z4' with a set of mostly stock Ceriatone Overtone boards.

[scotto]

Sounds like Jack Zucker has the mods sorted pretty well on the Ceriatone forum. Technical input credited and obvious (by that familiar tone) from Scott (and Gil). Worth checking out if you haven't already. Thanks to these guys for sharing what is no doubt hard won knowledge. I'll be doing mine this way ASAP.