Bassists! Anyone has got Info About the MXR M-80 Bass D.I.?

[zencafe]

Hello!

I was wondering if anyone has any info about this nice piece of bass preamp!?
If anyone has schematic I'd be more than glad about making, and indeed uploading a layout!
Or maybe some has a original one and could take some gut pictures? So that I could try to reverse engineer it...
I think this preamp and the Tech21 Bass Driver DI are the BEST bass 1overdrives ever made, well at least the best I've ever tried... hehe!
So does anyone have any info?

Here are some video samples:

http://www.youtube.com/watch?v=dBtBLIpB ... re=related
http://www.youtube.com/watch?v=i8Ag3vfH ... re=related

Thanks!

Greetings from Chile

D.

[Joe Hart]

This is what I get when I try to view the videos:

The URL contained a malformed video ID.

Anyone else having problems with them?

Also, I would be very interested in this, too!!! I am looking to make a bass DI box. Thanks.
-Joe Hart

[Ripthorn]

I have the same problem with the videos.  A bass DI is something that I, too, want to get working on at some point.

[slacker]

If you follow the link and then type mxr m-80 into the search box it lists all the videos that match. Hover over the links and compare the names to the broken links and you can see which ones zencafe was trying to link to.

[runmikeyrun]

I bought one last month based on lots of rave reviews @ talkbass.com.  It is a nice box, especially since it's way cheaper than the sansamp stuff.  I would take a pic for you but it's at our practice spot an hour away.  I will tell you though it's SMT and IIRC it's a 2 sided pcb.  I wanted to get in there and modify the distortion circuit and gave up when i saw the PCB.  I was unable to find a schematic anywhere.  For $130 i would just buy it. 

I'll copy and paste the review i wrote for it on talkbass.com, then i suggest you go try one out in the store, if you can find one (i couldn't).  I just saw a new EH product called the Bass Metaphors which is very similar to the M-80 for $120, might be worth checking out as an alternate.  Has everything the M-80 does except for a noise gate (which doesn't work well anyways) and it only has a two band vs three band eq section.  The most important part of these two pedals is the ability to blend in the distortion with your dry signal- this brought the punch and low end back to my sound while still affording me a great sounding distorted tone.

The review:

I picked this up based on all the rave reviews on here, so i thought i would write my own. I'll try to be as brief but informative as possible.

USE: I am using it as a preamp into a rack eq then into a QSC power amp going to an ampeg 8x10. I play an ibanez 5 string tuned A-D-G-C-F

FEATURES: If you don't know, look them over on the net, i'm not going to waste your time listing them all. Basically a two channel clean/distortion pedal with 3 band eq, noise gate, and clean/dist blend control for the distortion channel.

PROS:
-Good smooth distortion that gets mildly jagged and industrial sounding at higher settings.
-Blend control works well, but i feel it is too much of a fine line at the end of the control- the area to adjust a realistic blend of clean vs distorted seems to be all in the last 1/6 turn of the knob. Still, it's better than other pedals that don't have one at all. Basically the main reason i bought it.
-Most of the low end is retained with blend control turned to full distortion/no clean, but blending in a little clean brings the lost low end right back without a noticeable clean tone in the mix.
-Eq works reasonably well.
-Color switch effective in clean mode.
-Good headroom in clean mode.
-Parallel out works great for tuner because it's a dry signal. However, that doesn't really make it a parallel out, more of a parallel input.
-Came with a broken battery door. I sent tech support an email and pic of it and they replied about an hour later. Dunlop sent one out free and I got it two weeks later due to some sort of back order.
-Metal case and some of the markings are glow in the dark. Now, why aren't they all?

CONS:
-Not quite enough volume to drive a power amp's input. I had to turn the power amp way up to compensate. This makes it hard to judge how many watts i'm putting into the cabinet. Even with my amp and pedal at max i still couldn't get the clipping light to come on, i had to compensate with my eq's output control.
-The distortion is not as over the top as a lot of people on here would describe. I heard terms like "all you'd ever need" and "more than enough". Well, it's not. It's a grindy kind of angry SVT/Geddy Lee live tone. I expected way more gain out of this thing. Unfortunately it has the most gain out of any of the preamp pedals. I'm bummed i still have to use a DS-1 in front of it to give it the extra gain i need.
-Color switch on clean channel automatically activated in distortion channel so I have to compensate with a mid boost on the eq.
-Gate doesn't work effectively. It only reduces the volume. My bass still feeds back even with the gate on. This was another reason why i bought this over the competition.
-It came with the battery door broken, the latch was missing so the door wouldn't stay on. It is a very cheap piece of plastic that the battery snaps into. I snapped the battery out of it to put on the new door and the battery snap broke too! I should have ordered two.
-Surface mount construction, so I can't modify it. That's the fun part of a pedal- bring it home, find a schematic, and modify it to my taste.

DI FUNCTION: Did not get a chance to test. Will find out at the next show. I'm not expecting any surprises... i hope!

OVERALL IMPRESSION: A pretty good unit with some flaws, but i am pretty hard to please so you have to take that into consideration. My sound was really great last night, probably the best it's been in a long time. I had some punch and low end back to my sound which really helped me stand out among the two 5150s and wild drummer. That clean blend really worked miracles. Without my rackmount eq or sonic maximizer it still would have been a decent sound. Those two really made it into a great sound, but you could say that for almost anything!

[zencafe]

Thanks a lot! I'll be waiting for those pics!!

It's ok if its a two sided PCB... If the Pictures are Good enough, I think I could make it... Hopefully...
And yes, it indeed is not pricey, but I'm trying more to learn from it than actually using it, besides, I think us bass players could kindo use some more DIY projects hehehe...

Sorry about the broken links...

But, just type MXR M-80 in youtube and you'll get to a bunch videos...

Well, thanks again for the coming pics!

Greetings!

Douglas.

[Joe Hart]

Anything?

If not, does anyone have a lead on a schematic for a bass DI box? I've searched, but have only come up with what looks like "bare bones" schematic fragments or something like off a data sheet (which doesn't seem like an actual full schematic -- but I could very well be mistaken). Thanks.
-Joe Hart

[Monotremata]

Oooo havent even looked at this DI yet!!

Maybe you can help me out here runmikeyrun..
Im looking for something that gives me more 'grind' than fuzz..
Im currently using a Boss HM-2 with my Fender Jazz (tuned down to A) and through an Acoustic B200H with 2x15s..
I can get a nice fuzzy distortion tone but theres something missing in it..

Im REALLY trying to nail a tone like David Cochrane from the bands Head of David/God/Sweet Tooth/Jesu/etc or maybe like Bob Weston's tone on Shellac's At Action Park.

Heres Head of David's myspace page (band just recently got back together after 22 years)
http://www.myspace.com/headofdavidofficial

Over in their mp3 player is a track called Bugged which starts off with JUST the tone Im looking for. I am somewhat good friends with Dave ironically but he wont ever tell me how he got his damn sound. When Jesu came through town last year, his RAT had died the night before I met up with them and I swear he may have been using that MXR Bass DI.. He had just bought it that afternoon though and was having a hell of a time dialing it in during soundcheck cause it was too new..

Can this thing get me in that area or should I check out a Sansamp or something??

[runmikeyrun]

I checked out the head of david songs.  The M-80 should nail that tone pretty well.  With the dist maxed out it gets pretty industrial sounding and "grind" as you put it.  If you need more distortion (as i did) you can put a boost (or another dist set to low gain/high volume) in front of it.

[zencafe]

Well, just listen to Meshuggah and you'll see what's all the fuzz about .
So, does anyone have any pics that could share ?

Greetings

Douglas

[tommy.genes]

There's the Tronographic Rusty Box, which is supposedly a pedal version of the Traynor TS50B preamp used by Paul Weston of Shellac. You could probably find a Traynor TS50B schematic on the Internets...

http://www.tronographic.com/
http://www.youtube.com/watch?v=4TNtuJnJ9Zg

-- T. G. --

[Joe Hart]

The "Rusty Box" clip doesn't sound good at all (to me, at least)!! It's very thin and one-dimensional. But, I suppose, one could build it, then tweak it a lot to taste. But then again, it looks like a complicated build. It uses both 15V and 35V power sources, contains 19 transistors, an IC, and dozens of resistors, caps, and diodes. Hmm.

I was looking at this schematic: http://www.lynx.bc.ca/~jc/790713_TS50B.gif

Any thoughts? If I only needed the first part of the schematic (up to the "line out"), then it doesn't look bad at all. But the whole entire thing looks a little daunting to me. It looks like there are just too many places for me to mess up and I wouldn't even know where I went wrong!
-Joe Hart

[tommy.genes]

The Rusty Box tone in the demo video is not my favorite since I'm generally not a pick player, but it's not bad either. If you look at the knob settings in the video, the EQ if fairly radical, so it may get other tones as well. It is, however, the Shellac tone that Monotremata was talking about.

I have the same TS50B schematic, and I'm pretty sure that everything after the MASTER VOLUME pot is the power amp section, so you wouldn't need that for a pedal preamp build. That would eliminate the need for + 35V supplies at least.

If you are already not crazy about the tone, however, I'd look at some of the Runoff Groove projects like the Flipster or Thor first. Those are JFET-based emulations of tube amps, unlike the Rusty Box which is a direct solid state copy of a solid state amp.

HERE is a recent post of mine about the Thor for bass.

-- T. G. --

[Monotremata]

zencafe - what do you mean? Meshuggah hasnt had a bass player for quite a while now. Not since they both went down to 8 string guitars.

Yeah someone posted that Rusty Box over at the talkbass forums when I asked the same thing last week.
I didnt really dig it but yeah its Bob's shellac tone alright. Little too scooped sounding for me. Mids are where that grind I want comes from like on Godflesh records.

Think Im gonna grab that MXR (maybe put it on my xmas list for my girfriend to get me hehehe)..
At least if it doesnt work I can take it back to Guitar Center in 30 days..
I should just take apart my old Rat and find out why its intermittently working (think its the switch) cause the Rat is what David was using until his died in San Francisco last year.
But then again he also had a big Ampeg SVT with an 8x10 and my rig is just a lowly 200w Acoustic B200 with 2x15"s on it hehe.
Hell maybe I should just try my DS-1 on it..

[Joe Hart]

The Rusty Box tone in the demo video is not my favorite since I'm generally not a pick player, but it's not bad either.

I have the same TS50B schematic, and I'm pretty sure that everything after the MASTER VOLUME pot is the power amp section, so you wouldn't need that for a pedal preamp build. That would eliminate the need for + 35V supplies at least.

Sorry!! I reread my post and I did not mean how it sounded!! I just meant that it wasn't the tone I was looking for -- not that it was bad!! Sorry, again!

So, if I was to use everything up to the master volume, could that be used as a DI box? What I want to do is build two in one box (I run a stereo bass) and then be able to plug into any PA and get some sort of acceptable (for me) tone. I am not at all adverse to fooling around with the circuit, but I don't want to do all the work and have it not be a DI box!

Thank you!!
-Joe Hart

[zencafe]

zencafe - what do you mean? Meshuggah hasnt had a bass player for quite a while now. Not since they both went down to 8 string guitar

Monotremata, are you sure? -> http://www.youtube.com/watch?v=JOR0hUIGb4Y BTW He is using the M-80 on tha video... sounds just brutal!!

Regards

D.

[tommy.genes]

Sorry!! I reread my post and I did not mean how it sounded!!

No offense taken!

Building the TS50B schematic up through the master volume should be suitable for feeding into a power amp, such as through a dedicated power amp input or effects return on an integrated amplifier, or into a power-amp-only unit. That's not to say you couldn't run it into the front of the amp too.

What most people consider a DI, however, like the MXR M-80 or SansAmp BDDI, has a balanced output on a three-pin microphone jack. This makes it suitable for connecting directly into house/monitor mixing boards (hence the "Direct Input," or "DI" name). A very thorough explanation of this can be found HERE. Or else you can search these forums for established DI schematics/layouts that you can graft onto the TS50B circuit.

[Edit] This might make it a little simpler, you just want to make sure that you aren't overdriving the input of this chip - unless you want to, of course...

http://www.thatcorp.com/datashts/1600data.pdf

-- T. G. --

[Monotremata]

zencafe - what do you mean? Meshuggah hasnt had a bass player for quite a while now. Not since they both went down to 8 string guitar

Monotremata, are you sure? -> http://www.youtube.com/watch?v=JOR0hUIGb4Y BTW He is using the M-80 on tha video... sounds just brutal!!

AWESOME! Man I gotta get one of those with the next $140 I get haha!
Yeah wierd, I remember reading after Nothing came out (maybe it was around Catch 33) that they werent using a bass player on record anymore cause they covered all that low area themselves now.. (They did say regarding Nothing, they always wanted to do an album where both Thordendal and Hagstrom played bass instead haha).
I think they do take that guy with them live though.. Man last time I saw em was on the Nothing tour and I cant even remember anything about the show other than sitting on Thordendals side of the stage watching his head do those Jason Newstead headbanging windmills all night haha.

[kievblues]

I do not want to create a new topic, so I will ask here.

Can anybody tell what transistors and diodes are used here? In my scheme, nothing is clear. What is 1QL and 6YL? 
Link:https://www.dropbox.com/s/bdv0nxcz47drwpj/73304672-MXR-Bass-DI.pdf

[duck_arse]

the circuit itself is nice and clear. they look like the "markings" for surface mount parts. don't know how you'd find the part # from that though, I couldn't on googoo. maybe the experts could disect the functions and suggest work-alikes if you were going to build one.

[edit:] oh, and wlecome to the forum.