New HRM build

[ic-racer]

I realized I never posted this picture of the finished amp.
[img768]http://img.photobucket.com/albums/v670/ ... le-680.jpg[/img]
[img768]http://img.photobucket.com/albums/v670/ ... e-2373.jpg[/img]

[ic-racer]

Well, these things are never really "finished" so I'd like to update this thread with recent developments on this amplifier.

After building the Manzamp, I was so impressed with its sound, it made this HRM amp sound 'just average.' I realized that this amp should sound like the best amp I have ever played. So, I spend over a month working with this amp. Starting from the pictures, schematic, through the layout and the final build, I checked and double checked everything looking for some error.

I went back to the pictures and looked for clues. I noticed that the trimmers were fixed in place with the blue silicone. To me that meant that Mister D had put them in those specific positions.

It was curious that in the pictures the OD entrance trimmer is clearly at 1:00 in at least two picture sets. This is odd because this amp has almost no gain at that setting. Brandon even told me that when he builds this amp the cranks the OD entrance all the way up.

Then I noticed that in these same two amps the FET trimmer is cranked all the way up and glued in place. Putting two-and-two together I tried the combination of FET all the way up and OD entrance at 1:00.

Wow!, this is the 'secret' to making this amp come alive.

What an awesome OD sound. I don't know if I would have ever found that combination of settings by trial and error. Now the "Drive" control works in the 5:00 to 7:00 range (rather than having to be on all the way).

[sepulchre]

Beautiful job, as always. Are we going to get to hear this one?

Is the FET/OD entrance trick only true with HRM amps? Or would it also be useful on a 124? I guess the best way for me to find out is to build one and try it, which I intend to do but that won't be until next summer . . . I hope. So my curiosity is itching.

[dcribbs1412]

congrats ic-racer
great looking build
did you happen to measure the OD entrance trimmer setting

Darin

[ic-racer]

Beautiful job, as always. Are we going to get to hear this one?

Is the FET/OD entrance trick only true with HRM amps? Or would it also be useful on a 124? I guess the best way for me to find out is to build one and try it, which I intend to do but that won't be until next summer . . . I hope. So my curiosity is itching.

Looking closely at other 'guts' pictures the few that show the FET cranked all the way up were HRM-only amps. The "HRM Bluesmaster" picture I saw had the FET trimmer in the middle.

My 124 has plenty of gain without using the fet channel and with the OD entrance trimmer near the middle to 2/3 position.

Certainly there are different ways to build the FET circuit and bias it so the trimmer position in the pictures may not be useful, but I tried to build mine per the picture here. Also shown is #124 and you can see the trimmer is set to a lower level.

[img:996:327]http://img.photobucket.com/albums/v670/ ... posite.jpg[/img]

[ic-racer]

Here is the enlargement of the OD trimmer position showing that it is not cranked all the way up.

If you build the amp and put the trimmer there, the overall gain with OD and PAB is not much, it requires the "DRIVE" control to be full on. The amp sounds 'buzzy' and requires the HRM 'TREBLE' pot to be almost all the way off.

[img:287:264]http://img.photobucket.com/albums/v670/ ... rimmer.jpg[/img]

By running through the FET input, and backing off the OD trimmer, there is plenty of gain and less 'buzz' letting you set the HRM trimmers like in the picture, which is where I have mine set now:

[img439]http://img.photobucket.com/albums/v670/ ... ated-1.jpg[/img]

[ic-racer]

congrats ic-racer
great looking build
did you happen to measure the OD entrance trimmer setting

Darin

In-circuit measurement I get 9K from the wiper to the leg toward the front of the amp. Overall my pot measures 22K in-circuit.

[ic-racer]

Here is a clip. First solo is this amp, second is Larry with his fantastic WaWa solo from "Springville" on "Strikes Twice"

Settings on my amp were Gibson SG & Crybaby going into FET input, OD 1:00, Vol 3, Drive 7, Presence 5.
OD & PAB, Mid=OFF, Bright = OFF, ROCK= ON. EV12-S Ported cab.
HRM settings per picture above.

PLUSH Verbrator (Dumblator) with REVERB and BOSS DD3.

http://youtu.be/0Q9c6xJr2wI

[Guitarman18]

Thanks for sharing ic-racer. I really like those tones.

I've been planning on doing this HRM build for a while, but your comments yesterday about it sounding 'just average' kind of took the wind out of my sail. Earlier in the thread you said 'Wow, the clean channel is the best on any amp I have ever played!' Did the Manzamp invalidate that statement? Are the cleans still great, but the OD was 'just average'?

I was planning on leaving out the FET board but, in light of your recent observations, I'll find a way to get it back in there!

Cheers,

Paul.

[JazzGuitarGimp]

Great looking and sounding build, ic!

I have a question: What's your take on the hooping thing? Some people think HAD does it for secrecy, some think it affects the tone by keeping parts vibration-free.

ALl the best, and happy holidays to you!
Lou

[lord preset]

Great looking and sounding build, ic!

I have a question: What's your take on the hooping thing? Some people think HAD does it for secrecy, some think it affects the tone by keeping parts vibration-free.

ALl the best, and happy holidays to you!
Lou

I always assumed that there was a Korg Pandora hidden under the goop.

[Dr d]

Great work, as usual!!!! Your observational skills are amazing! Sounds great, but does this mean this amp can only really be used either in clean mode through the normal input, or overdriven through the FET?

[ic-racer]

Ok here are the sound clips.
I just did 3 takes. No tweaking, no tube rolling, no fancy mic position. I just set a mic in front of the cabinet, plugged in and played.

All Tracks
OD trimmer 1:00
FET trimmer: Max on
HRM treble at the dot between 2 and 3
HRM bass at the dot between 2 and 3
HRM mid at 2
Ported "Dumble-style" EVM 12-S cabinet, close mic.
Plush Verbrator and BOSS DD3 in loop


Track "L5"
http://www.youtube.com/watch?v=MdTesmrUOME

L5-style guitar, bridge pickup (PAF style pickup 500k pots, 11s)
Clean
Input: NOR
Jazz
Bright=off
Mid=off
Vol=2
Treble=8
Mid = 1
Bass=5
Master=8
Presence 6.5

Track "ES335"
http://www.youtube.com/watch?v=SnyQv3k0rkE

1990s ES335 with PAF style pickups 500k pots 10s
Toggle between OD (Drive 5) and clean
input: FET
Rock
Bright=on
Mid=off
Vol=4
Treble=8
Mid = 1
Bass=5
Master 2.5
Presence 6.5

Track "LP Standard"
http://www.youtube.com/watch?v=azztLlAJnTA

2013 LP Traditional with PAF style pickups 500k pots, 9s
OD (Drive 7) and PAB whole track
input: FET
Rock
Bright=off
Mid=off
Vol=4
Treble=8
Mid = 1
Bass=5
Master 2.5
Presence 6.5

[Ang3lus]

you should be a session musician or make your own cd, this stuff is incredible, tone feel and phrasing all together. the holy triad of any great artist.

the amps are amazing as well, can't wait to hear the manzamp

[groovtubin]

http://www.youtube.com/watch?v=gDgmsYDC ... e=youtu.be

Crazy huh, HRM circuits, one soft n sweet from iceracer, one on the edge of blowing up, that`s what i like most @ these circuits, so much variety! Straight into amp. Nice job iceracer!

jim @ OA.com