HRM reality sound check

[Tonegeek]

(amp is Skyliner, HRM, BM PI, 50 watt EL-34)

I always assumed the fattest sound I could get from my HRM was with OD, mid shift, and PAB on so I tweaked my amp for that. so this is what i ended up with:

OD only sounds mostly like the clean channel only with a little less bass and more breakup
OD+Mid Shift about the same but louder and more overdriven, maybe slightly more middy
OD+PAB is louder and definitely more middy (not unlike a tube screamer)- my least favorite
OD+PAB+Mid really fat, louder and more bottom than the other 3 - my favorite

The first 3 settings are limited but I can get some good SRV stuff going with OD+mid shift

Is this typical for this amp? If not, what should I be experiencing?

I would like to:
get more bottom on the OD alone (like the clean channel)
keep it from getting so middy on the OD+PAB setting (maybe the extra bass will fix this too)
Keep the fatness I now have when all 3 are on

my initial thoughts are I can up the coupling caps to get more bottom on the OD alone (already got 5uf across for all Ck) (maybe tweak the HRM bass trim too)

the real challenge seems to be to get the boosts to be less middy. That seems like it would require a different architecture altogether. Maybe I should explore the BM stack and switch the stack out by lifting the mid leg from ground (is this mega-boost?)

just looking at the possibilities...

[brewdude]

I haven't built an HRM yet, but I get the feeling that most people only use the OD with PAB on. I could be wrong, but the HRM tonestack seems that it would limit the gain too much without bypassing the Clean tonestack.

[stelligan]

Tonegeek,

FWIW - My HRM is skyliner, standard PI, Bassman power, 6L6.

Goosing my bass HRM trimmer fixed me good. From clean to OD + PAB is tone matched pretty closely - and that is what I shot for. I imagine my OD may not be as gritty as a BM PI - I dunno. I used to always use OD + PAB + mid before I adjusted the trimmer. Now I live without the mid boost except at times with Teles & Strats. I will even use OD without PAB at times, which I thought was taboo. Front panel tones at: Treble 11 o'clock, Mids 11, Bass 1:30. The logical approach for matching PAB tones to those without would seem to be getting the amp at clean or OD alone to sound right to you with all the tones at close positions to each other(I mean, where the HRM trimmers are). So, when PAB lifts the stack it is close to tonally the same - just more of it. Is my thinking flawed on this? Ex: If your tone controls vary widely from your HRM trimmers - the greater the disparity in those tones when PAB lifts the stack out.

Just rambling, I guess.

[dogears]

BM stack! Yep.

(amp is Skyliner, HRM, BM PI, 50 watt EL-34)

I always assumed the fattest sound I could get from my HRM was with OD, mid shift, and PAB on so I tweaked my amp for that. so this is what i ended up with:

OD only sounds mostly like the clean channel only with a little less bass and more breakup
OD+Mid Shift about the same but louder and more overdriven, maybe slightly more middy
OD+PAB is louder and definitely more middy (not unlike a tube screamer)- my least favorite
OD+PAB+Mid really fat, louder and more bottom than the other 3 - my favorite

The first 3 settings are limited but I can get some good SRV stuff going with OD+mid shift

Is this typical for this amp? If not, what should I be experiencing?

I would like to:
get more bottom on the OD alone (like the clean channel)
keep it from getting so middy on the OD+PAB setting (maybe the extra bass will fix this too)
Keep the fatness I now have when all 3 are on

my initial thoughts are I can up the coupling caps to get more bottom on the OD alone (already got 5uf across for all Ck) (maybe tweak the HRM bass trim too)

the real challenge seems to be to get the boosts to be less middy. That seems like it would require a different architecture altogether. Maybe I should explore the BM stack and switch the stack out by lifting the mid leg from ground (is this mega-boost?)

just looking at the possibilities...

[Fischerman]

In my amp, OD+PAB+Mid Boost was really fat...too fat for most things. I usually use OD+PAB. One thing that I found on mine was that running the HRM mid control at any sort of high settings was just too middy (harder to play as well). I almost never run the HRM mid control above half...which then requires me to set the HRM treble/bass controls lower but that's what works on mine.

[Tonegeek]

BM stack! Yep.

(amp is Skyliner, HRM, BM PI, 50 watt EL-34)

I always assumed the fattest sound I could get from my HRM was with OD, mid shift, and PAB on so I tweaked my amp for that. so this is what i ended up with:

OD only sounds mostly like the clean channel only with a little less bass and more breakup
OD+Mid Shift about the same but louder and more overdriven, maybe slightly more middy
OD+PAB is louder and definitely more middy (not unlike a tube screamer)- my least favorite
OD+PAB+Mid really fat, louder and more bottom than the other 3 - my favorite

The first 3 settings are limited but I can get some good SRV stuff going with OD+mid shift

Is this typical for this amp? If not, what should I be experiencing?

I would like to:
get more bottom on the OD alone (like the clean channel)
keep it from getting so middy on the OD+PAB setting (maybe the extra bass will fix this too)
Keep the fatness I now have when all 3 are on

my initial thoughts are I can up the coupling caps to get more bottom on the OD alone (already got 5uf across for all Ck) (maybe tweak the HRM bass trim too)

the real challenge seems to be to get the boosts to be less middy. That seems like it would require a different architecture altogether. Maybe I should explore the BM stack and switch the stack out by lifting the mid leg from ground (is this mega-boost?)

just looking at the possibilities...

I have been tempted to try this stack for a while. Guess I have to now!

In my amp, OD+PAB+Mid Boost was really fat...too fat for most things. I usually use OD+PAB. One thing that I found on mine was that running the HRM mid control at any sort of high settings was just too middy (harder to play as well). I almost never run the HRM mid control above half...which then requires me to set the HRM treble/bass controls lower but that's what works on mine.

Yea, I hear that a lot about not getting the HRM mids too high. I tweaked my amp to sound best with OD+PAB+Mid Boost but now I am thinking to tweak with just OD+PAB as the best sound. Then you still have some control over the tone using the clean tone stack. I think my friend who I built an amp for would like that especially.

[Fischerman]

I tweaked my amp to sound best with OD+PAB+Mid Boost but now I am thinking to tweak with just OD+PAB as the best sound. Then you still have some control over the tone using the clean tone stack. I think my friend who I built an amp for would like that especially.

I'm not sure I follow...when you use PAB the clean tonestack is defeated and doesn't operate.

I still haven't played a good non-HRM but IMLE I've always preferred distortion tones from a circuit that had no early tone stack but did have a late tone stack. So that's why I chose HRM as my first build...but it may be that I would have preferred a non-HRM. But I missed the boat on Funk chassis and won't buy one that says 'Dumble' on it...and it's gotta be 100W (so no Brownote or Ceriatone). So I may never get to try.

[phsyconoodler]

Ceriatone does a 100 watt version now.

So when you use the PAB it defeats the clean stack and defers to the HRM trimmers?Seems to make sense to me.
Never built an HRM yet.I've only had one request to build one.It seems most guys are happy with non-HRM.

[Tonegeek]

Ceriatone does a 100 watt version now.

So when you use the PAB it defeats the clean stack and defers to the HRM trimmers?Seems to make sense to me.
Never built an HRM yet.I've only had one request to build one.It seems most guys are happy with non-HRM.

OD+PAB or OD+ mid boost does not totally defeat the stack, but it does diminish it somewhat
OD+PAB+mid boost will totally defeat it.

[Tonegeek]

Correction: In OD+PAB the tone controls are defeated (although I noticed the mid control will still have a very slight but unuseable affect on tone). OD+Mid boost (shift) is the one that gives an apparent boost and still enables use of the tone stack.

[talbany]

I always thought for Strats and Tele's Lifting the clean channel's stack for a PAB was in my opinion better... More mid's a bit more gain and some low end to help thicken up the bottom.. Very nice..That doesn't seem to work as well with Humbuckers and higher powered pickups... Get's to muddy too me... For Humbuckers and higher output pickups Break the Bass and treble and lift the stack to taste.. seems to be the way to go for me... Has anyone tried Both Lifting the Clean stack as well as the OD BM stack... Been tempted...



Tony VVT