EL84hrm

[danotron]

love the riff at 1:19....yummmmm!

[Tonegeek]

As usual your clips are outstanding, even through my lousy laptop speakers.

[danotron]

Hey how about a schematic?

My AX84 sounds like ass...I'd love to have a EL84 HRM

<--I am green with envy.....

[mat]

Thanks everyone for the nice words and sorry for not answering earlier. Been busy at work but had a little time to tweak the build also and record couple of samples (with same recording setup as the first clips) with the latest changes. The recording volume was very neighbour friendly.

Clips are too long, you don't have to listem the whole lenght - I just had not time to cut and trim them. These are first takes - just noodling around (I promised earlier for myself that I am not going to send a half ready clips to the forum but I kind of like the sound of the MiniHRM.. not so much of the playing).

First clip is clean channel (midboost on, pab on) and after a while the od channel with very little od. I added little reverb on the Reaper sequencer software. http://soundclick.com/share?songid=8927753

Second clip is pab on, mid boost on, od on. Again added software reverb. http://soundclick.com/share?songid=8927752

Third clip is EH Memory Boy + tube reverb on the passive loop. I did not hear much delay on the recording so I added hall-type software reverb to the quitar tracks. http://soundclick.com/share?songid=8927754

I'll post the schem when I have time to put all changes to it. It will be nothing new I think.

One more thing. The amp feedbacks very nicely when opening the master volume(s). Not so much heard on the clips due to the low recording volume level.

cheers,

[Structo]

What guitar(s) did you use?

Sounds great!

[mat]

What guitar(s) did you use?

Sounds great!

Thanks!

Check the first post for the recording setup.

[Structo]

Ok, I thought the first clip sounded a bit like a strat so I wasn't sure.

[10thTx]

The power section is same as on AX84.com HiOctane. The mid pot is replaced by one 120k resistor. Pre volume is a trimmer (usually always on twelve o'clock on my d-style builds.) Bass and treble pots are still wired wrong way..krhm. The layout is far from as in original amps. The voltages are bit strange right now. 260-270V on the EL84. V1a,b about 155V. V2a 145V and V2b is 185V ??!!
PT is a small toroid. OT is Hammond 125ESE (IIRR).
The HRM settings are super sensitive for the OD sound. Bass trim is opened as little as possible. OD entrance trimmer is less than 50% on.

The preamp values IIRR are as on 101-HRM schem.

I'd love to see a schematic for this amp. That is some of the best amp tone I've ever heard.

With respect, 10thtx

[mat]

The power section is same as on AX84.com HiOctane. The mid pot is replaced by one 120k resistor. Pre volume is a trimmer (usually always on twelve o'clock on my d-style builds.) Bass and treble pots are still wired wrong way..krhm. The layout is far from as in original amps. The voltages are bit strange right now. 260-270V on the EL84. V1a,b about 155V. V2a 145V and V2b is 185V ??!!
PT is a small toroid. OT is Hammond 125ESE (IIRR).
The HRM settings are super sensitive for the OD sound. Bass trim is opened as little as possible. OD entrance trimmer is less than 50% on.

The preamp values IIRR are as on 101-HRM schem.

I'd love to see a schematic for this amp. That is some of the best amp tone I've ever heard.

With respect, 10thtx

Wow! Thanks. It is nothing really special. I have couple of days off next week, I'll send it then at the latest.

[10thTx]

I looked at what you mentioned with some of your comments and took a wild guess at what you might have in a schematic?

I'm not familiar with AX84 Hi-Octane?

Q1) what component values need changing in the schematic?

Q2) is the mstr vol prior or post to the DPDT?

Q3) are you using a tube rectifier or solid state (Hi-Octane's showed either

Q4) does yours have one single ended EL84 or are you using two EL84's
or the Hi-Octane with an EL84 & 6V6?

Q5) is the mid resistor shown correctly?

I can send you an editable ExpressSCH schematic to edit & post if that would be helpful to you?

I'd really like to see an accurate schematic.

With respect, 10thtx

[mat]

I looked at what you mentioned with some of your comments and took a wild guess at what you might have in a schematic?

I'm not familiar with AX84 Hi-Octane?

Q1) what component values need changing in the schematic?

Q2) is the mstr vol prior or post to the DPDT?

Q3) are you using a tube rectifier or solid state (Hi-Octane's showed either

Q4) does yours have one single ended EL84 or are you using two EL84's
or the Hi-Octane with an EL84 & 6V6?

Q5) is the mid resistor shown correctly?

I can send you an editable ExpressSCH schematic to edit & post if that would be helpful to you?

I'd really like to see an accurate schematic.

With respect, 10thtx

Hi 10thtx,

The amp is 101-HRM schem's preamp. No PI. Just single EL84. HiOctanes power section. I'll post the schem next week if I got a permission from HiGain to post it.

Until next week,

[10thTx]

Is it accurate to think that you're using the preamp and overdrive from the HRM into an EL84?

When you say power section, I'm thinking the power tube, B+ rail and PT etc.... not any of the 12AX7 tubes? Am I approaching this correctly? What kind of rectifer?

It's been awhile since I have been strongly interested in another amp but I am impressed with the tone of yours.

Thanks With respect, 10thtx

[jim]

Sounds great Max!

[mat]

Sounds great Max!

Thanks Jim. I tried the amp at band rehersals and it just dont have enough power for that kind of use. It will be my home amp. I'm going to make a small 1x12'' combo from it.
While running the amp louder, it soon lost that dumble feeling from it. I did not have the tube reverb on the loop. I wonder if that might help the case.

I have the schem ready as my amp is now but am still waiting for HiGains premision to post it.

[Colossal]

I drew up a schematic for Mat's amp and with his permission, I am posting it here. Mat has reviewed it for accuracy. The amp is a hybrid of a tweaked 101HRM preamp and a modded AX84 Hi Octane SE EL84 output stage. I have indicated value changes that Mat made to the original schematics as components drawn in red. Additionally, I have added optional circuits which are greyed out so as not to get in the way visually. Mat's amp is cathode biased with a fixed cap and resistor, however I have shown the modded AX84 method of using a lower value cathode resistor and a 1k 2W pot so that bias can be dialed in exactly to the desired bias. Finally, Mat modded the original Hi Octane power supply slightly and the schematic is drawn as he did it.

This is a great sounding amp! Excellent work Mat and Hi Gain. Gotta put this one on the To Build list.

(10thtx, this should answer all of your questions! )

EDIT: Updated schematic to clarify a couple of things and fix some typos.
UPDATED 4/11/10: Added bass pot jumper to PAB