Video of a high gain HRM 100

[massygt6]

Hi guys,
I've recorded a little video of my HRM, I play some heavier stuff and I like to have some gainy sound out of this amp...
The compression of the encoding has ruined a little the sound, but its still acceptable.
In the description of the video you can find the gear I've used.
Thanks for the attention.

http://www.youtube.com/v/S5EKyf4WUR8&hl=it&fs=1

[Guitarman18]

massygt6,

Absolutely awesome!!! Playing and tones.
Can you tell us what tweaks have helped you get your amp to sound the way it does? (apart from the billion hours of practise )

I'm in the middle of an HRM and it would be great to get somewhere close to what you have going on there.

Thanks for sharing.

Cheers,

Paul.

[massygt6]

Hi Paul, and thank you...
First of all, the voltages are significantly lower than the original.
I've got 410v on power tubes and in v1/v2 preamp section the voltages are about 180v, I can't remember exactly, if you're interested, when I will open up the amp I can take some notes about that.
I've got snubbers on V2, and as you know, an HRM should not have snubbers.
V1 and V2 values has some mods, that I can tell you, as said before, next time I will open the amp.
I've got a 25k gain trimmer installed in the back plate and currently I'm using chinese high gain tubes for V1 and V2, while for V3 I've got a Sovtek LPS.
The choke is 10H and the filtering of the power section has been increased a little to obtain less fubbiness in the bass frequencies, even if with a proper guitar and settings, the amp still blooms in a beautiful way.
The amp sounds a darker than the most I've heard, and the clean channel is still acceptable, not as beautiful as a standard configuration, but still pretty.
Note also that the guitar has some hot pickups
With a 335 or a Tele, the gain is not that high.
One thing that I forgot to mention is that of the original Ceriatone amp, the only thing that remains is the amp chassis, while the circuit as been rebuilt to exact ods101 specs as a starting point.

[Guitarman18]

Thanks for the info massygt6.

Did you deliberately lower your voltages or was that forced upon you, due to the trafo(?) you used.

Interesting about the snubbers, did you ever try LNFB in the HRM topology also?

I notice that you have your input volume dimed. I have a Bluesmaster HRM that becomes a different beast with that dialed high!

Where in the PS did you up your filtering?

Is you tonestack stock Skyline or have you made changes there also.

Do you have the 47pF cap bypassing the 470K on the OD input network?

Once again, thanks for sharing, and if you have any more clips, we'd love to hear 'em.

Cheers,

Paul.

[Structo]

I couldn't get the above link to work for me.
This is what I came up with.
http://www.youtube.com/watch?v=S5EKyf4WUR8

Sounds pretty good.
I love how you can pretty much cover anything with these amps.

[Drumslinger]

Very nice massygt6! Is that a Quadraverb sitting on top?

DS

[Bob-I]

Wow, you've got the gains really up there, mine D-Clones get muddy with it cranked that high, you're is clean and bright, bring on the bacon.

[massygt6]

thanks guys, I've got to say that there's a little buzziness in the highs, I'm noticing it now, but I think that the camcorder is responsible for that, cause live I can't hear that ringing noise...
The input volume is MAXED in the video
To answer some questions:
-no, until now I've not experimented with local feedback networks on this amp.
- I've got a 33pF ceramic cap bypassing a 390k resistor in the input OD network
-The filtering is increased with two 300uF 450v Philips caps instead of 2x220uF.
-The lower voltages are obtained with a proper dimensioned PT, bias is about 38-40 mA with a B+ of 405-410 volts.
-The tonestack is still standard Skyline
-The snubbers on V2 are 190pF, ceramics