RM100.. too bright?

[nikki-k]

Hi!
Well, I finally got an RM100. I tried a dozen or so modules in an RM100 in a Mom n Pop store a few weeks ago, bought the recto, and an RM4. I guess I got used to the RM4 with my modules.. playing it thru a solid state power amp thru a 2x12 with Greenback 25's. I have the RM100 going thru the same 2x12 and.. bright. Way bright. I had an Egnater Rebel, and sold it for this reason. Just could never tame the upper mids and the highs/fizziness/hair.

I have tried EL34L's, Ruby EL34B-STR (quad and pair), and then a pair of 6L6's. Even tried changing V1 to an old 70's Brimar ECC83 (wicked warmness usually, mid-gain; usually tames Marshalls and similar). Oh- V1 on the RM100 is the one closest to the input.. closest to the front.. right?

Maybe I am over-sensitive to hair/fizz/brightness?
(I own Top Boost, SL+, Recto and 1086 modules; love them with the RM4)

 

[okstrat]

I always thought of the MTS amps being too DARK overall.

 

[Dallas Marlow]

Hey Nikki,

In my personal opinion, most tube amps I've owned and play through v30's sound WAY to bright. Lots of guys use beam blockers, but really I've never had the need once I got everything set up properly. I always keep the treble cranked way down and purposely use darker pre-amp tubes for certain positions.

Here's some suggestions for you:

When you installed the new tubes what are you running your bias at? I've found that if you go for a browner sound on the power tubes it gets harsh, so I run mine at around 38 mv.

Cables, cables, cables. Some of the really "high end" cables are just to freggin high-fi to my ears and they carryyy soooo much more treble, now some people like this, but it drives me crazy. I actually use monster rock cables, and they are far to dark for some peoples ears, but I've found when you really start cranking a tube amp they get more high end when run through v30's (at least the ones in my 1960BV they are prob Chinese Celestions), at the highest volumes it smooths out but in general try darker cables. Do NOT exclude the speaker cable, unknown to most people it makes a HUGE difference in tone, along with the power cable... you might laugh but it really does. Are you running anything in the effects loop and are all your stomps/effects running a good quality cables.

I run the treble on all my mods at no higher than 10 o'clock for the most part, and I keep the presence at about the same maybe 10:30, try turning the resonance up just a little past mid it seems to thicken up the lower mids a bit too, at least to my ears.

Also, what ohm rating is your 2x12 running at I'm guessing 8 Ohms? If so that's to my ears the darkest sounding already. All different Ohm settings have different characteristics, supposedly 16 ohms uses all the windings on the transformers or something? I'm not sure... someone else could tell you more on that one.

Next, is your 2x12 an open back or closed back? Open back cabs sometimes have to much high end and seem ice picky.

I strongly dislike JJ EL34L's in this amp, I think they sound to mid scooped and the highs just don't do it for me at all. Try a quad of Tung-Sol EL34B, I'm not sure if they are anything like the Ruby Tubes you have but these tubes are very flat sounding, they don't have any pronounced areas on the sound spectrum to me. Supposedly they are voiced similar to original mullards, but I can't say that from personal experience. If you like more of the classic marshall sizzle, look for some Shuguang EL34B's 6th gen or later I think, they have more of a sizzly high end mid range thing going on.

Next bet, what kind of guitar and pick ups are you using, strings etc. will also play a role here.

Anyways, let me know if any of this helps at all. Maybe I can lend a hand if anything sticks out to me that I'm not thinking about.

Best of luck.

Dallas

P.S. come to think of it I found my grail module very treb heavy and run the treb pretty low on it, it's not TO far from your recto mod.

 

[Julia]

If you have an hour or so read through This Thread on speaker directivity. Bruce Egnater makes an appearance. I've tried the method described in the first four posts with good success. This version of the beam blocker seems to be far more effective and even, and doesn't create other problems like phasing that can occur using regular beam blockers like from Weber.

I've installed two 3/4" thick inside my upper 212cabs, and will be keeping them outside the on the lower 212. I've got a V-30 and a Greenback in each.[/b]

 

[jmgman70]

I always thought of the MTS amps being too DARK overall.

This would be my thoughts too!

 

[droptrd]

I always thought of the MTS amps being too DARK overall.

This would be my thoughts too!

I would concider Dual recs to be too dark. I wouldnt put the rm in that catagory IMO.

 

[6stringgrind]

I always thought of the MTS amps being too DARK overall.

This would be my thoughts too!

Me, too. I'm using EL34s with V30s in my RM100 and I run the presence at 3 o' clock.

 

[nikki-k]

OK... using an FRFR SS power amp as a baseline, pop a module from RM4 thru that into the RM100, and with Presence down ("off"), Density anywhere, and it is alot brighter... treble knobs on modules are not enough (nor proper, in this case) to reduce/neutralize the brightness, it makes me question the difference between the two units. After trial and error with various tubes in V1 of the RM4 (feeds every module), the 70's Brimar won out for mid-gain and warmth. Even so, the initial gain circuit is still a bit brightly voiced for me. My SL+ (post '07 factory JCM'd) gets the mid's almost slammed, treble noonish, bass 2-3 o'clock.

As a point of reference: most would not say a JCM800 is a dark gain amp. Budda SD(II) series, Mesa Lone Star, Carvin Legacy.. maybe even a Bogner Shiva.. these are dark. Too often, dark gain amps lose something in the process. Budda being an exception . My Legacy, which I have reworked and mod'd, is beautiful now. I can run it at a decent volume, and dime the tonestack (including the non-NFB presence) and pump it to my EV loaded 4x12 and it is STILL not a bright sound. Cuts, has body, almost hitting that magic I love just before crossing "the neutral zone." Mesa Lone Star, unmodded, would be too dark and one dimensional.

I will some stuff mentioned here, give it the "one week trial."
Oh- the speaker thing? I was very lucky early on; my Dad is a jazz musician, and one of his majors in college was acoustical engineering. Beam Blockers? Well... What Jay goes over in that thread is great info, totally accurate. Very knowledgeable guy. He was one reason I gave the Axe FX Ultra a try. The "foam ring trick" he suggests is a cool one. Used a variation years ago. Mainly, it will eliminate the frequency/directivity issues that live players encounter, but also has can impact recording environments. However, for what I am doing, I want to have the ability to move my relative position to really relate to the sound at different positions. Kinda like looking for sweet spots for future use while consciously auditioning the amp.

With the overkill of gain available in the modules (for my use/tastes), I am really tempted to try a 5751 (JAN Phillips) in V1 of the RM100, maybe even a 12AT7 if that fails. My Brimars couldnt do it

 

[nikki-k]

I always thought of the MTS amps being too DARK overall.

This would be my thoughts too!

Me, too. I'm using EL34s with V30s in my RM100 and I run the presence at 3 o' clock.

Whoa. That would shred my eardrums at any volume.
I love my EV's for the (close to) neutral tone. Greenbacks= mid hype + darker, V30's = please remove the icepick - lol!

 

[JKD]

If we're talking speakers..I'm loving G12H30s...they're the bog standard ones (actually the relabelled Hellatone 30s) but I have 2 in my Randall 4x12 to add warmth..with the v30s providing the punch.

I think people cranking the Presence might be looking for that razor sharp feel and edge that comes from a solid state power section...either that or something else very different about their setup...

The Presence taper is another factor here...it's quite subtle up until it's high ranges of course but then my ears are shot

 

[tlingen]

Has anyone heard of using that 3/4" foam (with 3" circles cut out) inside a 4x12 on all 4 speakers yet?

 

[okstrat]

You want to talk dark, my bogner ecstasy is DARRRRRK. I actually started modding the Randall modules because of the low mid thing the RM amps and most modules have to my ear... but hey, maybe 20 years of gigging have tweaked my ears a bit.

Pete

 

[nikki-k]

Ahhh!
OK, Ecstasy can be dark-er. I find the Shiva darker of the two, and the Ecstasy would be a decent example of a dark amp with (80's) *hair* on it, almost fizzy at higher gains. When I tried the XTC module, it recalled Bogner top end, but lacked the "body" that the Shiva has, and the Ecstasy can have. Make sense?

I just watched a Mesa vid with Andy Timmons, and the Lone Star in it is dark, but since he has a pedal (and magic ), it livens it up a bit. Maybe he did one of the mods for it as well, who knows. It is dark, almost too dark for me. Not enough bite, but the "hair" is rolled out tonally, which is hard to do with removing cut and bite... sorta like rolling ~5.8k out with a modeller to get rid of digital "hair n fizz;" it works, but kills what little upper end life it may have had.

Going to work solely with the SL+ and several pre and power tube combos, and try to get the interrelationship between module treble and head presence figured. BTW- anyone know if it is an NFB presence? One thing I love about Matchless is the cut Plus, going to try an MXR 10-band up front, no boost... diggin out some ECC803S's too

 

[nikki-k]

Tossed some 6L6GC in (2, runnin 50watts), Tung Sol reissue in V1, JJ in V2, JJ ECC803S (balanced) in V3. Tried Top Boost (v1=brimar, v2=jj ecc83s), SL+ (forget what I stuck in there-lol), ditto on the 1086. Set all to noon on modules, "bright" off/left, 1086 mid=left. Density and Presence at noon (after quick bias.. meter off head, plus bias probes to double check mA vs mV), Master then set to about noon, and started pushing up module masters. HUGE difference. Would love to know what happened, Tung Sol v1 from JJ v1 should not have been that huge. Maybe just got a nice set of 6L6's. Only had a matched pair, forgot to try them yesterday.

Want to compare to my Ruby EL34-B-STR's...

What I have now.. Top Boost is wicked articulate, gain is at about 8, maybe going on 9 o'clock at most. Picking dynamics are simply beautiful. No boosting, no MXR EQ.. Once I compare the Ruby's with the 6L6's I will try to get some clips...
Thx for all the suggestions! Tweaking Presence to *allow* the treble pots to *work* well was huge, plus the tubes. 1086 in "un-bright, un-gain" mode is the biggest surprise (a happy one ). Amp with all modules has a nice dark base(ment), and blooms nicely when pushed, and even with 6L6 vs El34, good big dog bark.

 

[nikki-k]

Oh! Another example of my kind of dark... Sarah Mclachlan's "Afterglow Live." Yeah, I know, it's a girl thing But, the one player- Sean Ashby- has great control over dark tones that bloom nicely. Other guitarist, name escapes me, also has it.

 

[okstrat]

Glad to hear you're getting it wrangled. I haven't looked or traced the schematic, but since it's in the power amp I'd wager the presence and depth controls are both off of the negative feedback and could be tweaked to taste pretty easily.

Pete

 

[jmgman70]

Tossed some 6L6GC in (2, runnin 50watts), Tung Sol reissue in V1, JJ in V2, JJ ECC803S (balanced) in V3. Tried Top Boost (v1=brimar, v2=jj ecc83s), SL+ (forget what I stuck in there-lol), ditto on the 1086. Set all to noon on modules, "bright" off/left, 1086 mid=left. Density and Presence at noon (after quick bias.. meter off head, plus bias probes to double check mA vs mV), Master then set to about noon, and started pushing up module masters. HUGE difference. Would love to know what happened, Tung Sol v1 from JJ v1 should not have been that huge. Maybe just got a nice set of 6L6's. Only had a matched pair, forgot to try them yesterday.

Want to compare to my Ruby EL34-B-STR's...

What I have now.. Top Boost is wicked articulate, gain is at about 8, maybe going on 9 o'clock at most. Picking dynamics are simply beautiful. No boosting, no MXR EQ.. Once I compare the Ruby's with the 6L6's I will try to get some clips...
Thx for all the suggestions! Tweaking Presence to *allow* the treble pots to *work* well was huge, plus the tubes. 1086 in "un-bright, un-gain" mode is the biggest surprise (a happy one ). Amp with all modules has a nice dark base(ment), and blooms nicely when pushed, and even with 6L6 vs El34, good big dog bark.

Sounds like you have a bad case of MTS :lol:

 

[Julia]

Another thing I found that works well in high gain amps is putting a JAN GE 5751 in the phase inverter... balanced? Hell if I know. Sounds good. Been using it on my 5150 for months. It's very subtle but it just makes the amp feel less compressed with the gains set high.

 

[nikki-k]

5751 is usually great for V1 (initial gain, uncontrolled/not potted). It is almost like a 12AT7 gain-wise, but also like a 12AX7. If the amp is being cranked (ie, dime a JCM.. lol..) then a balnced 5751 or 12AT7 can allow a little more headroom. If you use an amp that has been modded or written as having a PPIMV, sometimes the PI can be too harsh, as it is getting the full brunt of the preamp if nothing exists between. Pushing the tonestack by using a PPIMV will also change it's color.. VERY reactive. If the PI does not get pushed hard, sometimes a "thicker" type with some good gain will allow sort-of "pushed" sounding tones at lower levels.

I really thought an 803S long plate would have tamed things, but oddly the Tung Sol did it. I did put the JJ 803S long in the PI spot tho, which seems to have helped smooth things just that extra bit. Still have a JJ 83S in V2 for the effects loop, tho it is unused. From my understanding, the effects loop(s) remain in series in the path, thus V2 is contributing to the circuit all the time; to what extent.. anyone?

IMO, V1 is the most vital. Well, V1 plus that initial bit of circuit. It determines what the modules get fed; give 'em signal that is brittle, it cannot make it thicker cleanly. Give too much low end.. ugh.. tubby mess. If the section up to the modules is poop, it can only get worse- lol.

Off to swap in the Ruby EL34B-STR's. If the 6L6GC's (JJ) win.. wow.. will be another surprise. But, the set I have are really articulate, pretty full sounding.

 

[Julia]

What I haven't seen is the block diagram for the RM100. I know there are two tubes in each module. And of course the power tubes are on the chassis. What preamp tubes are not in the modules?