Distortion question

Is the distortion on an HD-130 coming from the solid state pre-amp or are the power tubes being overdriven? For example, if I turn up the pre-volume and keep the master vol at a reasonable level, am I getting true tube distortion or am I just driving the pre-amp as a distortion box? Thanks...

You are creating preamp distortion when turning up the input gain and turning down the Master Volume.
The only way to get tube distortion in a Music Man (other than using a tube preamp ahead of it) is to turn the Master all the way up then increase the input gain until you can drive the output tubes into overload.
This only happens at or near FULL OUTPUT POWER and it is really LOUD unless you use a speaker emulator or "hot plate" load box to absorb all the excess power.
I did this with my 410-65 in a small club but I had it on low power (35 watts). It sounds REAL good and MM amps can do this well because of their high-headroom preamp which can still be clean at the tube's overload point (not all amps have this same capability and add their preamp distortion as well).
Steve

Steve,
What kind of attenuator did you use? I have been kicking around the idea of doing that as well with my 410-sixty five. Nothing like power tube grind! Weber makes one that will handle 50 watts - I was thinking that one with the amp on low power (i'm always on low power)? Would like to hear what one you had success with. (Some, like the marshall power break, I have heard nothing but bad things about).

i have a buddy who has a BF super reverb, and he uses a weber mini-mass to get a great grind at very reasonable volumes. I like the music man when I crank the master and get the preamp to 4 or 5 (my preamp distorts around 7 or 8 depending on guitar pickups). I'm think thats the way to go. Assuming I use the right ohmage load, and have the amp on low power, do you see any red flags to my OT health?
And on a 4 10 are my speakers four or eight ohms?

I have a weber mass-100 attenuator on the way I got off of EBAY for a really good price. It should be here wednesday or thurs. Once I get it I am going to test it with my Peavey classic 50 to make sure it works right, and then cautiously with my music man. My hope is to use my 410 sixty five with one of these to get power tube distortion at varying volumes. Even though the attenuator supports up to 100 watts I don't ever intend to use it with the high power setting.
I'll post here and let you know how it works. If it sounds bad I will E-bay it back and just use a ts-9 tube screamer. I know the tube screamer is a good sound, but everybody I know uses one with a clean amp, i want to be different. My hope is I will max the master and control the compression and breakup from the channel volume. We'll see. My amp works fine with everything maxed on low power so as long as this device is in good working condition and I match the ohms I think I shouldn't do any harm. I'm gonna get a real good quality short speaker cable too (hopefully like 1 foot).

I went home at lunch and my mass arrived. I wanted to bring my musicman up on it VERY slowly and cautiosuly, but I couldn't help trying it out. I tried with my classic 50, max attenuation and just cranked it's clean channel to MAX. Let me tell you, my classic 50 has NEVER sounded better. I will try my MM 410 after work tonight and let you guys know how it sounds.
PS - I will never use this while playing at home. Enough heat was coming off my classic 50 to heat my whole apartment!!!!!

Cool! The 4-10" speakers (if using the factory standard series/parallel wiring) will exhibit a total load impedance of 8-ohms.
I have a few Groove Tubes Speaker Emulator boxes (older styles) and a few PS Systems "The Power Tool" that I use from time to time.
The Power Tool units are cool because they take the output of the load and feed it to a built-in EQ section, speaker cabinet emulator and 50 watt solid state amp to drive the speakers at any level you want. The EQ allows you tailor the sound to your taste (3-band active EQ).
I always use the Music Man amp in low power mode when using a load box/emulator to minimize the stress on the output tubes and transformer.
Interestingly, I have two tube amps that have load/emulator/simulators built-in! The Groove Tubes STP-G and the PS Systems EB100S (www.eb100s.com) can both be used as a line-level source of screaming output tube distortion to feed effects, or fed to headphones or right out to a speaker.
Steve

Thanks for the info. I really like this Weber attenuator. I had tried a Marshall power break with my classic 50 back in the day and it sounded dreadful, so I was a little worried. I was worried since this one was designed for a 100-watt amp that the treble would be under-attenuated or over-attenuated. It sounds natural though, and so far (at 'bedroom' levels), the amp "responds" very naturally, it seems. The real test will be at my gig tonight.
I did an A/B test high power vs. low power, and I didn;t notice much difference. So I will be sticking with low power all the time. Less stress, and less HEAT!! Summer is coming and I don't want anything to melt. Especially my transformers. I have a little cyclone fan I am going to throw in my gig box too so if it seems extra hot back there, I can turn on and let it cool the tubes.
The sound I am looking for is just basically that "rounding out" of the singal, when it just starts to clip and compress little bit, so I am pretty excited for this tonight.
Sure a lot better than a power brake!

btw - I "ohmed" my speaker plug with an ohm-meter at lunch to be sure - i got a reading of 5.1 ohms. That would suggest 4 ohms? I guess someone wired them differently along the way?
I tried a single 8 inch speaker and i got roughly 8 ohms.

Normally an 8 ohm load will give you about 6 ohms of RESISTANCE. If your meter is not real kosher, thats probably an 8 ohm load. A 4 ohm load typically gives around 3-3.2 ohms resistance. Your 4-10 should be wired up at 8 ohms. Thanks to Steve for correcting me on that one LAST time. That's what's cool about this sight-NO EGO PROBLEMS. THe other combo amps with two speakers like my 2-10 are 4 ohm. If you measure an 8 ohm speaker and got 8 ohms, I'd calibrate my meter! It does make me wonder about YOUR amp though if you measured your total load and got 5.1. Measure each of your speakers seperately with the plug pulled from amp and see what you get. Are all the speakers the same? What wiring config are they in? Should be series parallel to get 8 but if you have a clinker in the pile. it can mess up the total.

I will do that - I have been wondering. For the record I did my gig last night (4ohm setting), with the attenuator... it sounded GREAT. This is really the sound I have been looking for! The other interesting thing is the weber unit's circuit makes my reverb sound better. As far as my ear can tell, the signal gets compressed so it brings out the reverb a little more - makes it sound deeper. This could be the amp too, but I don't rememeber it sounding like that without it.
If anyone out there is looking for a nice bluesy sound out of their MM, but doesn't like the pre-amp distortion, and wants to be different and not use a tube screamer, this is they way to do it. WOW! I feel like I have finally found the sound I have been looking for for a long time!

I'll have to check out that Weber load. I am always looking for new solutions that work.
Mike already covered the meter/resistance/impedance thing so I have nothing more to add.
Steve

Cerebral,
I'm thinking about using an attenuator too. But is it really worth it, or should I just stick to the tube screamer thing?
Also, my amp tech told me attenuators are not meant for use with 6L6 tubes. Is this true?

Its hard for me to say if the attenuator is worth it for you. I guess it depends if you are satisfied with your TS sound or not. I love the sound I am getting (got to do it at a gig Sunday afternoon) but it may not be what you are looking for. I don't know that any tube is 'meant' for an attenuator. But I know two guys with super reverbs that use them and get great sounds, and I think those are 6l6's. Maybe he means he doesn't think they sound good dimed?

He told me that's what he read in his THD catalogue. Maybe he just doesn't know. He only uses Sovtek tubes too. When I told him I was sceptical he said only "freaks" don't like those tubes.
Anyway, I'd have to mail order that Weber mass, so I want to make sure it works well for a nice warm overdrive. I don't like that preamp gain, tried it with tube preamp pedals too, just not my thing, so I think power tubes is the way to go. At least I hope so...
Greetz from Belgium.

THD makes their own attenuator, called the hot plate, maybe they were saying there's weren't designed with the frequency response of 6L6's in mind. I know two other guys besides me in my area that are using the Weber mass unit (they told me about it) and they play Super Reverbs, one guy a black face, the other a master volume with some modifications. They both sound great and Supers do have 6l6 power tubes.
If in doubt if you don't mind the long distance you can call Ted Weber directly and speak to him. He could probably tell you. I'd be interested to hear what he has to say. I got mine on Ebay so I never got to deal with him but I have heard he is real helpful and knowledgable.
Also, when I got mine (won for a good price on Ebay), I figured if I didn't like it I would just sell it again. Might be a possibility for you. I would say the sound qualifies as a nice warm overdrive - not too saturated unless you start to turn the preamp up and mix it's distortion in - but definetly a good bluesy sort of sound with sustain. Makes the reverb more present to my ear as well.

I just ordered a 50 Watt Weber Minimass. Will this go along with my 112 RP 100 on low power setting?

I mean, I hope my amp won't exceed the 50W rating...

If you keep your amp on Low Power, it ought to be fine.
Steve

Chris have you gotten it yet how do you like it?

I did get a letter from Weber saying they shipped my order. Still waiting for it. In fact I was just starting to get a bit worried...

Hey Chris any luck yet? I let my friend borrow my 100 watt one to try with his blues junior, it sounded very cool with that amp as well.
I've decided with my 410 Sixty Five, to always bring a little fan along, to plug in to blow on the back of the amp. (I plug it right into the outlet on the amp and turn it on low). It is doing some hard work and most of the clubs i play in are barely air conditioned ! I noticed the top of the amp warm to the touch (actually, I noticed this without the attenutator but of course with it it was a little worse). I just sort of point the fan at the tubes. It's ineffiecient, but still the tiny airflow that gets through makes a diffence - i don't notice any heat buildup anymore. I figure this sure isn't hurting.
I use a cheap little 'turbo' fan from walmart but I am sure there is a better solution - i believe mike kaus wired in a little muffin fan and mounted it ??
It sort of makes you wonder why classic amps never had a little fan for air flow? I mean they built these music mans and fenders so the heat from the tubes RISES into the chassis...
How many famous Jimi Hendrix / Who / Stevie Ray Vaughan / Clapton amps that you always read about in interviews "melting down" could have been prevented with just a little more air??

something definitely went wrong with the shipping. Mr. Weber graciously offered to send another one. Oh, I really do hope it will be OK this time.

*#@&***!!!
Hardly posted the previous message, when I found a card in the mailbox, saying my package had arrived. Wrote to Mr. Weber he didn't need to send another one. I was glad to find they were indeed as helpful as you told me...
which is something I can't say about the Belgian post office. For a 100$ miniMass, it cost me 48$ on shipping, which I had to wait for one and a half month. Now they add 20 euros on taxes. That makes almost 175$ for a 100$ miniMass. I hope things run smoother with DHL or something.
Let's forget about it. It came at last and I'll pick it up tomorrow!!!

So did you get it?

YES! I've got it at last!
Well, I haven't used it at band level yet, but here are some of my first impressions after my first day of minimass use:
- with the master at 10, and the gain at 0, I expected a bit more tube breakup. The sound is a little bit rounded but not much. Of course, this happened at bedroom level, with almost maximum attenuation. I'll wait until I play with my band. Also, I had my RP112EVM reviewed by my local music store (I'm not a tech, I don't want to do this myself) and they put Sovtek 5881's in it, saying "those are just the tubes everyone uses". I read on this forum Svetlana or GT are much better, so I want to check that out too.
- turning up the gain, it was easy to get different sounds while keeping the overall output level low, a bit like having an external volume knob that doesn't affect the sound. So, for the moment, the big advantage seems to be that you're able to have different overdrive settings, without having to worry about the volume. I only used the gain settings up to 5, it gets too cranky to me at higher levels. There's something in the gain that I don't like, sort of a "gritty" or "sandy" quality, which I try to tweak away. I read in another topic that a bad sounding gain could be because the amp needs a cap job. With the master vol at 10 and the gain at about 2-3, I really liked the sound.
My temporary conclusion is that I'm happy with it, offering me a variety of overdrive possibilities without the use of any pedal. Yet, I'm wondering how the use of a different brand of tubes will offer me a more satisfying power tube breakup. Keep in mind though that I still have to use it in a group setting, so I'll keep you posted for a more definitive opinion.

No offense but the plot against moose and squirel tubes(Sovtek) have a lousy rep as far as I'm concerned. Usually, when I hear a vendor say something like, "that's what everybody wants", it's usually what THEY carry so of course that what they want to sell. The GT's have not been going long enough to get much of a rep yet. The only 6L6 type tubes I'll use right now are the REAL svets(winged c) or the JJ's. The JJ's are a little darker sounding and if your amp has a little too much bite and you want to take some of the edge off, these are the ticket. Of course, if you have the money, NOS RCA's, Sylvania, Tung sol, are still great but my gawd are they high.

Thanks for the advise, Mike, my MM is indeed very bright. I'll see how easily I can get those JJ's. That's usually the problem over here, less choice, more cost.

Hi Chris,
I *think* that sandy/graininess you refer to is the odd order harmonics the preamp distortion creates. I like it for some things (hard, more rocky stuff) but for bluesy stuff i'm not so hot on it. One thing I noticed is when you have the power tubes cranking their even order stuff, and then add the preamps odd order stuff, it sounds REALLY cool.
I think you will be pleasantly surprised in your band situation. At first, at bedroom levels, i was excited that i was getting the power tube break up, but the sound was a little 'flat'. As soon as I brought the amp out to a gig though, and turned it up just a little more, it REALLY came alive. It may be because I am using a 100 watt Mass with a 65 watt amp (that is almost always set for half power).
When I first got my music man I didn't read the board thouroughly and went out and bought groove tubes (replacing what was in there when I got it). They were about $50 and sound fine, but - the guy who owned the amp before me (who is out about 5 nights a week) said they needed to be replaced every 4 or 5 months. I play out once or twice a week if I am lucky, and on low power most of the time to boot, so I can't wait to see 8 or 9 months down the road what the JJ's will sound like. Over here we can get a matched set for less than $30.
I am using a JJ for my phase inverter, I'm not sure it has effected the sound a whole lot though. I just know I like it. And it was peace of mind knowing i had a good quality tube in that critical location. Let us know how it goes in the band situation!!!

Well, it took some time, was on vacation, but I finally used the minimass with the band. Well, it was just... great! Didn't want to stop playing. From fat blues clean to real warm rock sounds. (I admit I didn't turn the gain higher than 7) I get all the versatility I want, and the sounds are real good. I knew it was a good deal when I bought that Musicman some months ago, but without cranking that power amp I was still looking for a good overdrive (and I was never satisfied with pedals) With the minimass I just get that big fat tone I always yearned for.
Also like to switch from clean to overdrive with only using the volume pot - just love to do that!
Yes - I love my Musicman!

Chris, glad you like it !
I am still quite in love with the sound too. I wonder though if I could get more gain in the power section (more breakup) by disconnecting the tremelo circuit. Anyone care to comment?

I see a lot of attenuator use here. A guy at THD said to not use his 'yellow jackets' on MM's. He added that class B amps don't like attenuators either, saying that at high voltage class B power is unstable as snot. Well, I use EL 84's quite often in my beater 65 combo. Anybody else like this sound? It is a different sound, like a smaller Vox, chimey, lots of break up. Do this only at low power, I am told by everyone here. Is this true as well for attenuators?