Just finished my OTS HRM 50w build. I finished the head cab today, it was my 1st try at tolexing so there is some room for improvement!

The amp is sounding very good, I have burnt in for about 12 hours so far,  with smooth lead tone and a full clean but I haven't really cranked it yet. I also have a VVR ready to fit if only I could find somewhere to put it!

I have -  Hammond 290 DEX PT, Hammond 1760 OT, a choke (Hammond  10H and 4H - 10H is in at the moment) and resistor (470R) switch, an HRM lift switch (thanks to Henry at Redplate) .

V1 OS Telefunken
V2 OS Teleunken
V3 Sovtek LPS
V4 and 5 TAD 6L6 WGC

I would say so far I am very happy with the HRM and you can dial a huge variety of sounds.
I have a Midiverb 4 for some delay and reverb through the loop, but it is quite a problem dialling this in so it sounds good on OD. It looks like I will have to build a tube D'lator, I already have the tranny and rack case

The wiring was all neat and tidy until I started tweaking, adding the choke and HRM switch and swapping the choke over...  honest. Still it is only my second build so I am sure I will get better at it! There is no hum or noise until you engage PAB and non HRM and goose the level, and then it is just VERY loud! The noise seems less than any old Marshalls I remember.  At lower jazz levels, it sounds great with the old G12 -65  - bass is quite tight.

Yes mate, just come in from the garden, I have done 4 of the edges. I did build a jig and the router is mounted in to a B&D workmate. Just push the panels across the router bit, nice square cuts, move the jig and cut the next one, easy.

The last one I did in pine, and it cut cleanly. This 18mm ply disintegrates as you cut it

I have started to cut the vertical cuts with my saw so it doesn't splinter too much.

It will all look lovely when it's finished and covered in sexy blonde tolex... mmm

Many thanks for that Erwin, I found that I hadn't connected the ground to the FET simulation resistor (220K) on the right
I now know how to tweak the voltages on the pre amp and that is another thing learned

Once that was done, I am now getting 194 or so on V1 and 205 on V2, which should do fine. At low level, it sounds fine, hopefully today I will get a chance to crank it a little

I have a choke /resistor on a switch, which I can hardly tell at low volume and an HRM lift which really does boost it but I kinda like the HRM sound. PAB on and HRM off turns it really wild

There sure are a lot of tones in there, I'm loving the clean too, even the Strat sounds really jazzy if you play with the options!

All in all I am very pleased with it. I'm just building the head cab today, got to finger joint the panels, no fun, I can tell you!


Thanks mate
Cheers
Rog

Hi there,
I have just finished my C'tone build and it is working pretty good. Sound is coming along as I am burning in and tweaking my trimmers.

My main concern is voltages with the Hammond 290DEX (for UK).

On V4 and 5 I am getting 470-474V with TAD 6L6 WGC and V1-1 is a bit high at 207V with an old Telefunken. I have tried some different V1 and V2 tubes but it seems about the same.

V3 is a Sovtek LPS balanced up at around 298V.

I have attached the layout showing where I was told to look at dropping the voltage to V1. I have tried some different values but I can only get the voltage up not down.

This is only my second build so I am no expert. I really would like to get the V1 down to 195-200V as this would be a good starting point for tone tweaking.

Nobody said this was gonna be easy..... Cool
Thanks
Rog

Look forward to it, mate Any extra info is always good.

Thanks
Rog

My OTS HRM 50w kit arrived today! Shipped Monday, delivered by UPS, after handing over £50 in VAT Oh well.

Boy it was well packed! Took 15 mins to cut the plastic wrap off.

I have started to assemble the chassis and sort out the resistors. I have a Hammond 290 DEX PT and 1760 OT, hope they will be fine and that the relays will be powered OK by the 5V output.

I also bought a VVR for installation at some stage and Nik supplied a tranny for the D'lator I will scratch build when all this lot is up and working. Lots to do.

To be honest it is a little daunting as I have only built one amp before, a 5W SE5a Ampmaker, but it works well and sounds great.

Question is, will I ever use it once the OTS is running

Xavi, why not build your own, these cabs seem quite expensive. Get the Vox type grille cloth if you like, though. There is a guy in the UK who builds similar (Marshall-style) head cabs at under half the price and they are very well made too.

See here http://www.ampmaker.com/cabs-by-chris-1142-0.html

I built my own head cab for my SE5a from 22mm pine which cost £20 including the handle and when I get my Ceriatone I will build one from ash (not volcanic!!!!), which may cost some more.

http://i451.photobucket.com/albums/qq233/rogerHW80/bentley_se5_2.jpg

There are plans here, perhaps you could get a local woodworker to put one together from these specs.

See here http://ampgarage.com/forum/viewtopic.php?t=10444