anyone use a bluetube or realtube?

I used to have a rackmount RealTube which I rewired as a BlueTube (the difference being how much distortion you wanted). The RT started audibly distorting at "2" and the BT was a lot more gentle and sounded like music until "5" or so.

I'm not crazy about distortion on a bass, but I thought the BT did a nice job.

 

See my review at:
http://www.bgra.net/reviews/tubeworks-rt904-1-rvw.html
Another one:
http://www.bgra.net/reviews/tw-bt-rvw.html

There are some good reviews on Harmony Central too:
http://www.harmony-central.com/Effects/Data/Tube_Works/Blue_Tube_Rack_Preamp-01.html

 

I use a Blue Tube as my pre, not for distortion per se. It starts distorting w/ the gain at 3, so that's where it stays. I haven't tried all of the other models, but those I've heard are great!

 

ooo -- good thread...I love those things!

Has anyone ever used a Blue Tube pedal as a preamp, straight into a power amp? Is there enough boost to act in lieu of a rackmount pre??

Thanks!
-Aram

 

It's been almost 10 years since I did it; I got a schematic from the manufacturer. It was just changing a couple of parts to increase the gain of the tube stage.

 

Has anyone swapped tubes around?

What kind of tube comes standard in the Blue Tube?

What kind should I put in to get more gain before distortion?

 

I have a NOS 12au7 in mine and like it. A 12at7 is worth a try also. It comes with a 12ax7 and it is a bit harsh to my liking - better for guitar. The 12au7 might be too "soft" for some people. The 12at7 probably will appeal to the most. the 12ax7 actually has the most "gain" - changing the tube type just really changes the "hardness" of the overdrive and the 12au7 is so low gain that it adds a LOT of warmth to the sound even below clipping - but again some might call it muddy?

 

Cool, I'll try the 12au7 next week. I mostly want to turn the gain up past 3 and stay clean so I don't have to dime the master.

 

You won't get more gain that way - but you will be able to dial up the gain knob more before it sounds harsh. What power amp are you trying to drive? The Blue Tube may have to be maxed on the master with some amps. If you never use the overdrive sounds of the Blue Tube I'd say you would be better off with a cleaner preamp...

 

No, I like the dirt, I just want a hotter output. If I could leave my gain at 3 and turn the master to 12, that would be fine too, but I don't think that's possible. I use the edge of the overdrive (gain at 3), but never full blown distortion like I get w/ the gain past 5. I'm driving a mackie 1400i -- I can just get it to clip w/ my active basses but not my passive ones, so I'd like a bit more output.

 

I have a Blue Tube 904 rack mount unit that I used for years. I retired it when I changed my rig up a while back. (Yes, I'm keeping it!) As far as tubes, the 12AX7's are too rough sounding in the unit for my tastes. I have tried every 12AU7, 6189, 5814, 5963 etc. in it that you can fathom and the best sounding one of all is the RCA 12AU7A "clear top". These are highly regarded as some of the best sounding 12AU7A's ever made. Pic below. These are readily available via ebay and, IMO, the best tube for this unit. YMMV.

 

Perfect, I'm sure you saved me some time.

Is there anything special to watch out for when I open the unit (904), or is the tube replacement pretty standard?

 

Had one years ago. I liked itvery much but I got G.A.S. for a night bass systen with the X-15. Also I had a Bass Harmony unity that was a fun one.

 

OK, I tried 5 different tubes today, and I think I've found one for my tone. When I opened it up, there was a Groove Tubes 12AT7 in there. I like it, but I was looking for more room on my drive knob. I tried a GE 12AX7 and a Sylvania 12AX7A. They were not that different from the GT, breakup too soon around 3. The top candidate was a Tungsram 12AU7, it let me turn the drive up to 5 and still get good tone. Then I thought I'd try the RCA 12AX7A I use in my practice combo ('78 Fender Musicmaster Bass). It's hot like the other AX7s, but the bottom is much tighter, I like it a lot! I don't have the room on my drive knob I wanted, but I'll just keep the Tungsram handy if I decide I *really* need to go to 5. All of these tubes are old and used, I've had them for awhile but never done anything with them.

Edit:

A couple days have gone by and I'm back to the 12AU7. It is smoother and quieter and has just made a great pre even better!

 

I just received my Blue Tube 903 pedal yesterday. it came from MF with a cracked Ruby 12ax7. Rather than send it back, I installed a friend's used Mullerd 12ax7 into it on a trial basis. It sounded OK. After reading the posts here, I went and bought a GT12au7. I'm looking for that vintage warm tube bass amp tone, you know, the warm gritty drive just short of breaking up. The GT 12au7 sounds a little better to my ears than the Mullerd. There seems to be a very slight bump in the mid bass though. I'm still getting familiar with the pedal and its 3 band EQ, and will keep you posted.

The other interesting thing that I thought I'd share is that the 3 band eq does not work the way you might assume it does. I thought that the tone is flat at 12 o'clock, you can then cut or boost, and that each tone control is independent of the others. Well, when I talked to Scott of Genz Benz / Tube Works I found out that it's not so. The treble and bass nobs are flat when dialed all the way to the left. The mid nob is flat when dialed all the way to the right. The tone controls interact with each other, so if you change the setting on one control, you affect the tone of the other controls. Don't ask me how. So, I've been playing around with it in the living room for an hour trying to figure it out. I'm going to take it to a "orginal classic rock" studio session tomorrow and try it out. We'll see what the engineer thinks. I won't be surprised if he tells me to give a rest, since he's got a bunch of high-end tube preamps that he can run me into, LoL!!!

 

That is how "classic" fender and marshall tone controls work. Ampeg tone controls are different, more like you'd expect. Check out this great "simulator" program to see the curves the controls give yah!
http://www.duncanamps.com/tsc/index.html
I did "mod" the center frequency of the mid control, see my former post for a pointer.

 

I've used real tube and blue tube. Great tone , unfortunately there just wasn't enough of it to really use them as preamps alone and they were a bit hissy.
If you could get another 10 or better still - 20 db gain out of them they'd be excellent bass preamps IMO.

 

I've got a B. K. Butler Tube Works Real Tube Overdrive which I bought 20 years ago.

It still has its original 12AX7 tube and works fine except that it seems to start rolling off the lows around 80Hz or so.

My questions to those who've used this unit are:

Will swapping the 12AX7 for a 12AU7 extend the Real Tube Overdrive's apparent low end?

Or, since this pedal was designed for guitar use and thus may have a high-pass filter, is there a mod to wrangle a deeper bottom out of this thing?

Thank you.