Ceriatone Overtone HRM100 MKIIR: Build Thread

[Vostre Roy]

Greetings fellow SSOers!

Been a while since I've posted gear, its actually the first thread I start with the new website design, hope everything will work.

A couple of months ago, I took the plunge and finally bought another amplifier kit, after building three from Weber (8CM100, 6M50P and Halle) and Bruce Egnater's Boutikit, this makes it my 5th amplifier kit that I'll try to bring to life. Although its not my first build, I still consider myself a rookie and I take my time putting this one together as it is so far the most complicated amp of all the kits I've did even though the boards came already assembled (it was the only option available on the website). So to spice things up a bit and to give myself more room for customisation, I've decided to get a blank chassis and do all the routing myself for the first time, results will show that its not my forte so far ahaha.

So lets get this thread started, I know you are here for some pictures anyway! Sorry about the quality of some pictures in advance, the lightning in my workroom is hard to handle.

Here's both transformers and the choke, freshly arrived from Ceriatone in Malaysia. I can't speak about the quality yet but Jesus Christ on the cross eating Doritos, the power transformer is huuuuuuuuge. Like almost twice as heavy as the one I got in my 8CM100.

The filter cap board, with "Holy Grails" electrolytic capacitors. I actually never heard of them, but I find the name quite funny, especially in a Dumber Overdrive Special clone ahaha

I like how the resistors are hiding under the capacitor, but I hope I'll never have to replace them lol

And here's the internal tonestack, the first reason why I wanted to build the chassis myself. In this circuit, the signal goes through the clean channel and EQ control, then at the switching system, it either goes through the PI or through the Overdrive channel. The internal tonestack is located after the Overdrive's last gain stage, pretty much like in a Marshall. Problem is, that second tonestack is only accessible from inside the chassis, which I find stupid (I don't blame Ceriatone, they wanted to do a Dumble clone and thats how they were made). So I will remove the trimpots from the board and run wires to potentiometers that will be accessible from the front of the amp, pretty much as the Weber Halle is made (which is Weber's take on the ODS circuit).

The blank chassis, an Hammond 1444-32

Using my AutoCAD skills, I've drawn and printed all the holes that I'll have to drill or cut. But since I wasn't paying enough attention, I've drawn the front pannel backward. Oh well, lesson learnt, at least I've noticed it before I've drilled anything (but I did punched all holes center, should be covered by the front pannel anyway)

The back pannel, at least I got that one right lol

And the result, once all holes are drilled and cut. I've used my dremel for the IC socket and the power transformer's hole so excuse the sloppy result, it was the best I could do with my skills and tools

Allright, that'll be it for today, as my internet connection is really slow right now. I'll post another bunch tomorrow, stay tuned!

Y.V.Roy

 

[Vostre Roy]

Allright, lets try to upload a few more pictures! All that I'm posting now has been done in the past 2 months, on my next time off I should be able to complete it since all I have left to wire are the potentiometers basically

So here's the fit test to see if my holes were drilled properly. I had to rework on the power transformer's hole a bit since it was tight but beside that, everything went smootly

Allright, now let the fun begin, heaters wired up tight and clean

Bias pots and sockets to get the readings installed. First time I use that kind of socket, usually I would just open the chassis and measure directly on the 1 Ohm resistor but those really work well, I bought a bunch of extra and will probably install some on my Weber amp aswell

At this point, the power tubes are pretty much all wired up beside missing the grid stoppers

Finally (for now), this is the amp as it was before I've worked on it on my last time off. Totally forgot to take picture before I left for work so as soon as I'll get back, I'll take some pictures and update this thread.

At this point, the power transformer was all wired up and I was beginning to wire the preamp tubes

So thats it for now! Was quite a challenge with that internet connection but once I'll get back to my place I'll try to take pictures everyday I work on it so stay tuned, more are coming in about two weeks.

Cheers!

Y.V.Roy

 

[mnemonic]

Very cool, I love seeing amp builds like this.

Do you have any mods in mind, or are you just going for the standard build?

What kind of sounds do you expect out of this amp? I don't know anything about Dumbles.

 

[Vostre Roy]

Very cool, I love seeing amp builds like this.

Do you have any mods in mind, or are you just going for the standard build?

What kind of sounds do you expect out of this amp? I don't know anything about Dumbles.

Here's a list of the mods that I'll be doing as of right now, the list might change down the road:

- Internal tonestack will be replaced by an external one, accessible from the front of the amp instead of inside it
- OD trim pot that is usually at the back of the amp will be moved to the front aswell
- Bright switch will be an actual switch instead of a push/pull pot
- Add a real Master Volume, will try the London Power's Phase Inverter Master Volume (not a Pre-PI or Post-PI, it actually sits inside the Phase Inverter, first time I'll try it)
- Added a Depth/Resonnance control

As for the sound itself, I've obviously never heard the real thing so I can't tell if it'll sound exactly like a Dumble but the other guitarist in my band has a Weber Halle, which is Weber's take on the ODS circuit. Its an amp that has a vintage type high gain sound (think early 80's high gain), darker than a JCM800 since its a bit more American sounding. The clean itself is probably one of the best I've heard so far. Many player describe those amps as being really responsive to pick attack and has a lot of harmonic and I can attest that its quite true, at least in the Halle's case. I'll know for sure about this one in a couple of weeks.

Cheers!

Y.V.Roy

 

[Vostre Roy]

Allright fellas, I'm back at my workplace for the next two weeks so its time to post what I've done during my last time off. To be fair, I haven't done as much as I would have wanted to, but I had to find the issue my friend's Weber Halle had (turns out his power transformer fried and we have to change it).

Anyway, back to my build, I took a picture before touching anything because I forgot to take some when I left the last time, so here's what it was like:

Now time to line up all the pots to make sure I don't mix them. Since I couldn't get all the values that Ceriatone uses (I've bought them seperatly on Next Gen Guitars), I went with the closest I could get. There wasn't a 1 Meg push/pull available either for the bright swith so it'll be wired on a DPDT switch instead.

Desoldering the internal trimpots. As I mentionned in my last post, I will use the board but just run wires to pots that will be accessible on the front of the amp

Couple of pots wired, couple of shielded wires ready and installed, other waiting for the right moment to install them. I've also wired the three switches for the Rock/Jazz, Deep and Mid Boost switches. It look like a mess right now but I'm not done with them. I just ran out of time as I've done that the last day before I flew out for my workplace, so here's the last pictures before I come back and (hopefully) complete the amp.

Close-up of the three switches. As I said, this is only a fit test, there's some clean-up work to do lol

And here's the three pots that are replacing the internal trim pots. Should do the trick just fine

So here's the update, I'll post again once I get some stuff done. I'm also currenly debating which tubes to use, this amp is designed for EL34s but I feel like some EH6CA7 might suits it even better. If anyone has any input on those or just want to share their experiences with other EL34s type of tubes, go ahead! I've only tried Tung Sols, JJ KT77 and E34L and Chinese EL34B.

Cheers!

Y. Vostre Roy

 

[PBGas]

Nicely done! What an amount of work that goes into building. Hope it all turns out well.

 

[Vostre Roy]

Nicely done! What an amount of work that goes into building. Hope it all turns out well.

Thanks man, it still look like a rat nest right now but in the end it'll be a bit cleaner.

And yeah it take times but its better to take the time to build it properly and have it working on the first try than mess something and having to figure it out after it has been powered up ahaha.

Its a fun hobby though!

 

[Vostre Roy]

Greetings Folks!

So its time for another update, and this is going to be quite a good one. The amp is alive!

I was seriously expecting something to go wrong, I mean this is the most complicated amp I've put together so far and I also modified a bit of it too but damn, this thing just fucking roar. 100w of pure tonal bliss, nothing that could possibly make for the insane price tags that original Dumbles are going for on the used market, but this is possibly my most versatile amp to date. I don't think it would handle modern death metal at all, but anything going from clean to vintage high gain sounds gorgeous out of that head. I've driven it through my two 4x12", its awesome. The London Power master volume does the trick quite well, I didn't notice much of tone loss at lower volume and the sweep continue to give volume all along the potentiometer range (as in it doesn't top at 12 o'clock and distort the poweramp after).

Every switches seems to be working as intended and the Preamp Booster (PAB) fonction, which is footswitchable, allows a tighter overdrive and works great for solos. I've driven a BYOC Parametric Overdrive to tight it all around, gotta fiddle a bit more with it as the EQ differs a lot with my Weber 8CM100.

So anyway, that pretty much sums it up as of now. I was able to use it for two entire band rehearsal without having anything failing which makes me really happy. On my next time off, I'll try to record something but I seriously sucks when it comes to recording stuff so don't hold your breathe, just believe what I say ahaha

To be able to carry it around without breaking anything, I've built a small headshell out of wood that I've recycled from my pool deck, gives it a redneck style for now but something better will be made in a near future.

Now, pictures!

Preamp tubes:

V1: Genalex Gold Lion ECC83S
V2: Preferred Series 7025
V3: Tung-Sol ECC803S

Poweramp tubes:

V4-V7: Electro Harmonix 6CA7

 

[Vostre Roy]

So thats it for now. Should you have any questions or comments, feel free to ask, I'm at my workplace for the next 10 days but once I come back I'll try to have some clips recorded.

Cheers!

 

[Kyle Jordan]

Excellent work.

I've been looking quite seriously at a Ceriatone SSS clone and your posts are fueling that desire.

Looking forward to the clips in the future.