An HRM I like - And just how much do I like it?

[ayan]

As I said in a previous post, I finally got my once HRM, then non HRM, then HRM again, amp to a place where I like it. I also indicated I wanted to try the amp at a gig to see just how well it did. All of that has happened, so here is the description of the beast:

1. Basic HRM configuration with 350pF treble cap
2. V1 and V2 with 220K/3.3K 150K/2.2K bias, 5uF cathode bypass
3. Skyliner EQ
4. Pre OD network: 470K//47pF + 100K + 100K trimmer with 4.7K tail
5. 330pF cap at V2's sockets
6. 180K V2B grid stopper
7. Drive control is 250K audio, but with a 100K resistor between input and wiper. This is an old trick of mine from 1999 that, to me, makes the HRM have a much better transition from low gain to higher gain settings (for the same HRM settings, of course)
8. No lead master brightness cap
9. PS dropping string for V2 and V1: 22K, 2.2K

I finally could say that I liked the tone of the amp. Gary asked me if I was taking it to a gig I had last night, and I talked to Gary and told him I was taking two amps to the gig: the HRM and my 100K non HRM. At sound check I dialed in both amps and things sounded pretty good. The HRM really loosed up at club volumes and sounded very sweet, with a fuller clean than the non HRM. I called Gary and mentioned that the two amps actually sounded very similar in a band context, etc.

I did the first set with the HRM and it was a good sounding amp, friendly at giving up some of the goods I like (read: harmonic feedback and sustain), and producing a bit of a violin type of tone. I fired up the 100K non HRM for the second set and suddenly, it was like I had been deaf all night long. There are just no two ways about it, the non HRM is much more suitable for my taste and playing style. Clearer string to string separation, more natural clean to OD transition and, basically, the ability to sound "clean" at high gain levels by controlling touch. This thing reminds me of the sound of a harpsichord instead of a violin.

Like at the last gig, where the 100K amp made its debut, people commented on how good that amp sounded, and I agree wholeheartedly. For the record, my 100K amp was a higher plate non HRM in a previous life and was never spectacular sounding. Nothing special about it, it's the only amp I have ever built that has New Sensor -- both PT and OT -- Marshall style transformers (I have used the PT in many other amps, a great PT IMHO).

The 100K amp is deceiving: harsh at home and doesn't sound so complete without the Dumbleator. But it has turned into, possibly, the best amp I have played through live. I glad I didn't sell it, after all.

Gil

[Mondoslug]

Interesting. It's good to come to decisions. Is the clean channel & clean channel with boost vastly different between a non HRM amp & HRM amp?

[ayan]

Interesting. It's good to come to decisions. Is the clean channel & clean channel with boost vastly different between a non HRM amp & HRM amp?

Strictly speaking, only in that with one or two exceptions out there, HRM amps don't have local feedback in the second clean stage and non-HRM amps do. The feedback changes the character of the clean sound, making it more bandwidth limited and perhaps a little more sustainy (due to the perceived added midrange), and it also reduces the amount of gain somewhat.

Folks other than Dumble have broken this rule and thus Glasswerks and Two Rock, for example, incorporate a switch to engage and disengage the feedback network I'm talking about.

Gil

[talbany]

Gil

The 330uf caps at V2's sockets did you mean 330 pf snubbers?






Tony VVT

[FUCHSAUDIO]

I agree with you. As someone who's built mainly non-HRM's in most of my ODs and TDS amps, it comes down to two types of tone and if it fit you personally.

I've heard people get stellar tones from both topologies, but it all depends on the player, and what he wants, or what works best for his playing style and guitar/pickup choices.

[talbany]

Amen Andy

This is why we decided to go with the HRM in our PC board designs, gives the player more room for tweeking the OD tone..
I like the Non HRM's better with humbuckers and the HRM's better for Strats & lower gain single coils.. There is no accounting for taste...


Andy will you be @ the Jersey amp Show?

Tony VVT

[FUCHSAUDIO]

So this is actually a D-style amp ? Funny how Rick Derringer told me it was (at the Dallas Guitar Show), and then a few people on the web denied it. Not that it matters, whatever works for you....

We'll be at the NJ show indeed. A new amp(s), Our pedals, a new speaker cab.

Hope to see you there.

[heisthl]

This is why we decided to go with the HRM in our PC board designs, gives the player more room for tweeking the OD tone..
I like the Non HRM's better with humbuckers and the HRM's better for Strats & lower gain single coils.. There is no accounting for taste...
Tony VVT

My experience varies in that I think the OD character for strats is better with non-HRM. With HB's either HRM or non-HRM can be great. JMHO

[dogears]

Obviously all the circuits have a place and their respective fans.

I'll add that my current main amp is set up HRM, but with Bluesmaster clean stack, mega boost, and some alternate plate/cathode values. It is set up specifically for the Dumbleator. This is one of the keys, IMO. Also, the cap size on OD1.

It is ridiculously delicious in every way and I can't imagine anyone playing it and then a non HRM and not digging the HRM as much. But again, personal tastes I guess.

[talbany]

Andy

Yeah it is a D-style amp without all the switching on the front. The Derringer has the 4 6V's Mercury Mag Tranny's..etc..
Pretty much a straight HRM....
Sorry I won't be able to make the show. Brooks and Dunn are in Baltimore both Lou Toomey and Tony king are playing VVT's now pretty cool so am going to hang there...
My partner Jim will be there w/ my good friend Bill Holter... Will meet some other time..
would love to plug into one of your amps have heard lots of great things about them.. Good Luck!!!


Tony VVT Amps

[ayan]

Gil

The 330uf caps at V2's sockets did you mean 330 pf snubbers?

Tony VVT

Minor typo. Sure, pF.


Gil

[ayan]

Obviously all the circuits have a place and their respective fans.

I'll add that my current main amp is set up HRM, but with Bluesmaster clean stack, mega boost, and some alternate plate/cathode values. It is set up specifically for the Dumbleator. This is one of the keys, IMO. Also, the cap size on OD1.

It is ridiculously delicious in every way and I can't imagine anyone playing it and then a non HRM and not digging the HRM as much. But again, personal tastes I guess.

I would love to be able to play a totally tweaked out HRM, like I suspect your amps are. I have played a few of them, including some my own, and while I have liked some of them, none has actually totally blown my mind. What is a thing of beauty to me about the non HRMs -- because I am so used to them -- is the natural progression from clean to OD then to OD + PAB, having similar usable tones along the way. I would love to get some of that in the HRM, but every change is big: from clean to OD and from OD to OD + PAB.

Cheers,

Gil

[talbany]

Thanks Gill
I am making a Non HRM for a Lap steel player and will try your values looks good.. I am using Twin style power and Opt on this one... although I like the Marshall style (New Sensor) Tranny's a little better...
I'll let you know how it turns out.. Thanks



Tony VVT Amps

[dogears]

Gil, the thing I love so much is that this amp is so transitional. My PI is standard, not the BM. But, all else is BM. It is really cool! It has none of the edginess, and the master bright cap is pretty big (as seen before). It really mates well with the Dumbleator capacitance.

Obviously all the circuits have a place and their respective fans.

I'll add that my current main amp is set up HRM, but with Bluesmaster clean stack, mega boost, and some alternate plate/cathode values. It is set up specifically for the Dumbleator. This is one of the keys, IMO. Also, the cap size on OD1.

It is ridiculously delicious in every way and I can't imagine anyone playing it and then a non HRM and not digging the HRM as much. But again, personal tastes I guess.

I would love to be able to play a totally tweaked out HRM, like I suspect your amps are. I have played a few of them, including some my own, and while I have liked some of them, none has actually totally blown my mind. What is a thing of beauty to me about the non HRMs -- because I am so used to them -- is the natural progression from clean to OD then to OD + PAB, having similar usable tones along the way. I would love to get some of that in the HRM, but every change is big: from clean to OD and from OD to OD + PAB.

Cheers,

Gil

[ayan]

Gil, the thing I love so much is that this amp is so transitional. My PI is standard, not the BM. But, all else is BM. It is really cool! It has none of the edginess, and the master bright cap is pretty big (as seen before). It really mates well with the Dumbleator capacitance.

I never tried that combo. I had all BM at some point, then regular HRM with BM PI, and then regular HRM top to bottom. Never tried thr BM amp with non BM PI!

Of course, I can't argue with the way YOU sound through those amps, any of the HRM variety for that matter. It is the way I sound that I am not so crazy about, whereas I can get a lot more mileage out of the non HRMs -- especially in terms of vocal type of feedback. Let's face it, the non HRMs are easier to play, there, I've said it.

Gil