Another "mystery tube"- NoMeansNo's Rob Wright, help me make a tube pre?

[soggybag]

I'm not a troll, I've been posting to this forum for a decade. I just read the article in your original post and I believe the whole thing was written tongue firmly in cheek. The guy has a sense of humor, where's yours? I'm totally capable of accepting the fact that I may be wrong, I only posted my opinion of the article.

I do believe people put tubes in amps. I do believe that people modify their amps and do all sorts of crazy things. I also believe there are no real secrets to getting a great tone. I don't believe the hype and the magic claims. I feel the tone of the article is having fun with this.

I saw no means no back in the early 90s, they were great.

[Earthscum]

http://www.nomeanswhatever.com/forum2/viewtopic.php?f=2&t=4970&hilit=tube

(pg1, big mike) "And he plays through a 4-12" cabinet instead of a more traditional 2-15" style. That's where the low-mid 'growl' comes from that most would try to get through Gain. A 4-12" allows all the highs to cut through and pushes the lows into a nice big fat bass wave. Very similar to Lemmy."

(pg2, lowdowndave) "I once spoke to Rob at a gig about this amp. I'd remembered reading in a bass gear interview him saying this particular amp had a single tiny valve in it that was responsible for his bass overdrive/distortion, and he even reiterated this when I spoke to him, but I'll be damned if I can find any valve/tube in this thing. Not a lot of info on this old beast on the internet, but I'm pretty sure it's solid state, so I don't know what Marshall did when they built this thing to get it to sound the way it does, but whatever it was, I'm glad they did it!"

(pg2, goukifrog) "For the marshall 3530, it is a mosfet amp, not just solid state (it's a solid state technology that behaves somehow like a tube, but with the solid state reliability and all).
There are some distortion pedals that can achieve a tone quite similar to Rob's tone, and I think more especially of a french guy's handmade pedals: Mazzette pedals.
This guy, Nico, who is building those devices is very kind, and has put on his myspace page quite convincing sounclips : http://www.myspace.com/mazzette

Otherwise, I think that the precision bass is a very important ingredient in order to obtain Rob's sound.
Note that he often plays cheap precision copies, just to underline that you are not necessarily condemned to buy a fender all american expansive piece of wood ;-)
That demonstrates also how important the amp is to sound quite like that...."

(pg3, goukifrog) "First, I'd like to underline that Rob got his Marshall around the time that Andy left the band (maybe Mr. Chedsey could be more precise about it, which for sure would be precious for us :roll: hum... John, Are you here?).

That said, Everything from the beginning to 0+2=1 was recorded with an amp from the brand "Acoustic", I dunno the exact model.
So we obviously can obtain this Rob-sound with an amp that's not necessarily a Marshall."


So, with just that, I don't care about the tone, again. I've begun to understand what all the hype is about tubes. That's all I thought it was, but recently I've payed enough attention to who's playing tubes and who plays SS. There's a difference. I'm at the point where I'm just about to use what I have with a tweak or 2 and call it good. I already have 5 forms of distortion... for a bass. The thing is that even the best tone stacks can't trim the highs in the same way a tube does, and I really don't want some emulator circuit. I can build jfet circuits all day long to do just what I want, but it's not a tube, and that's what I want. No mojo or hype. Just a nice tube pre before the signal gets sent to DI and/or the amp. If I can coax it to grind when I'm slamming the strings, then YAY! my only other goal for this is met. I got some distortion overdriving the most recent setup, but it was a bit more harsh than I wanted.

I think I'm gonna try the mosfet boost one more time, without the tone and see what I get. I think that should be good to start with, then I can bounce back to the tube.

[Earthscum]

Alrighty. then... I've been looking around for this. I saw mention some time ago about strapping caps across the heaters and using pin 9 as a Vref for an op amp. I can't find where I saw it, though.

Like this:

(pin4, 6V+) CAP (pin9, Ground) CAP (pin5, 6V-)

Heater resistance is 40R (80R series, 20R parallel), correct? ((12V/150mA)/2=40 Ohms)

So I could use 470uF or bigger caps. Is this possible, or ok? Not recommended? My thinking is that the extra filtering couldn't hurt, I have pin 9 just hanging out all by it's lonesome now, and, shouldn't the op amp help cancel out any of the remnant humm at the rails?

If it's a "go ahead", I expect that I should change the pi filter as suggested earlier by splitting the resistance and running half on each rail to balance things out?

[harmonic]

Just wanted to interject at this point and say that I played my bass through a Valvecaster that I built for a guitar playing friend and was really impressed at the life it brought to my sound. It's super super easy to build — maybe worth a shot?

[nexekho]

Indeed, my Valvecaster seems to pull extra life out of other pedals although its standalone tone isn't the best.  It makes my wah sound amazing compared to how it is with the POD.

[Earthscum]

I have definitely considered the Valvecaster. I think, though, that is gonna be a separate project. I was listening to some clips the other night and am pretty impressed. I even have a good wall wart for it. I was thinking (last night) about just putting a Valvecaster and a Spark Gap in a box together. I think the Spark Gap with a clean blend would sound huge!

Basically where I'm at with this right now is a copy of the Marshall 3530 input http://www.drtube.com/schematics/marshall/3530pre.gif, skipping the active EQ. After some more reading and digging, I discovered Rob used an Acoustic (brand) amp through their earlier stuff. The IBS stuff didn't come out until mid-late 80's. So, upgrade to a marshall SS probably ended up in some not-so-favorable distortion, or none. It may have sounded a bit dry.

One forum I was reading had a couple members that confirmed that it's basically the IBS amp + the 412 cab. Apparently Rob has been playing J pickups with no change in sound (guess he doesn't like taking his vintage out on the road anymore, and his mexican fender finally gave up). I (re)discovered something... if you have a mid-cut in the dry signal and you overdrive it, the bass and treble get the clipping and the mids start to shine through and retain the clarity in the signal, and give it an apparent mid boost.

So, basically a 5x fixed gain stage, followed by a 10x adjustable gain stage, tone shaping, tube+tube, IC buffer, out (with DI out). Since I don't have to worry about batteries, and it's going to BE my pedalboard, I'm considering throwing in something like the Tiny Giant amp, as well as LED VU meter.

Now... I guess I'll just try running the TL072 like I mentioned above... I just wish I could find where I saw it mentioned about using the heater PS and taking advantage of the heaters' split resistance. I just don't know if it's safe, more than anything.