MESA D-180

[440Hz]

I just recently purchased on of these with a really low serial number (called Mesa and they said it was probably made around December '82) and am trying to get some feedbac/suggestions from people on here who have had or has one.

The cascading distortion on here is AMAZING! Hands down BEST bass fuzz I have ever heard. Doesn't suck all the low-end outta the bass. I recall reading another post on here about this about and the owner nearly epoxying the knobs in place. The Master on here if moved a hair jumps like 10dB seemingly.

I would love to be able to use it as a two-channel amp and last night tried running an older (passive?) AB box to each channel. When doing this though and if running in Channel A (overdrive input) the volume drops to nearly zero but if you unplug the Channel 2 input, the volume jumps right back to where it is supposed to be (i.e. loud). Seems like there is some sort of circuit design that doesn't let you AB the channels in this way to get a rich fuzz channel (Ch1) and a great clean tone (Ch2).

Any feedback etc would be much appreciated. I thought of taking it to my amp guy to see if he could customize it to work the way I want it to.

Would a non-passive AB box be the way to go?

[lbwdog]

In the early days of Mesa bass amps, you had to special order them from Mesa. I did this and my amp's serial number was either 0093 or 0097 IIRC. I was looking for an SVT type tone, but didn't get it. Although I liked the amp, I used it till sometime around 1985 and traded it for some other bass gear including a Yamaha PB-1 preamp.

[440Hz]

this paired with my 70's SVT frankecab loaded with Eminence Delta's sound nothing short of amazing.

[anderbass]

Originally Posted by 440Hz

I would love to be able to use it as a two-channel amp and last night tried running an older (passive?) AB box to each channel. When doing this though and if running in Channel A (overdrive input) the volume drops to nearly zero but if you unplug the Channel 2 input, the volume jumps right back to where it is supposed to be (i.e. loud). Seems like there is some sort of circuit design that doesn't let you AB the channels in this way to get a rich fuzz channel (Ch1) and a great clean tone (Ch2).

Yeah I tried this too and found the cascading preamp feature wont allow an ABY box to work like it would with a non-cascading 2 ch. amp. When you input the D-180 channel 2 (with channel 1 volume on) it back feeds your basses signal back into the output of ch.1. That's why the D-180 manual recommends turning ch. 1 volume all the way off when using ch 2.

This mods gonna be kinda tricky, be sure to let us know if your tech figures out a good way to pull it off.

[440Hz]

Right now I am using a volume pedal to back the gain down andget a cleaner sound.will work for now but it would be ultimate to have full access to both channels. Perhaps when they reissue it?

[gastric]

Booooo, I was entertaining a D-180 and using a BOSS LS-2 to channel switch. You just killed that idea.

[NecroticImbecil]

It mioght be cheaper to get another amp for clean than to have a D180 modded. Consider also that the mod to make it a workable 2 channel amp might very well mean eliminating the cascading channel feature that makes the amp so great in the first place.

[Mojo-Man]

This is one of my all time favorite amps.

Killer tone, with the right wattage to crank live.

A Mesa D-180 through a Bergantino NV 215 or NV 610 is tone heaven.

[anderbass]

440Hz, I've been thinking a more realistic option might be using another stand alone preamp for your clean tones and the unmodded Boogie's preamp section just for your dirty channel.

If you used a Y-cord to split your basses output into the D-180 Ch1 input and your other preamps input.

And then plugged your AB box "A" input to your other preamps output.

And then plugged your D-180 Effects Send jack to your AB box input "B".

And then finally plugged your AB box output into the D-180 Effects Return jack you could have foot a foot switchable 2-channel setup without modding your D-180. (If you used an ABY box instead of a AB, you'd actually have a 3-channel setup cause you could run either channel alone or both channels simultaneously)

ps:
Something of related interest I recently learned with my D-180 while using it as a power amp (inputting its Effects Return jack with another preamp) Is the D-180 Master Volume feature of additional distortion at lower knob positions still worked just exactly the same w/o using the D-180 preamp section.

[440Hz]

My amp guy said he could make some sort of switch for swapping channel inside the amp and not do anything destructive to the amp. Soon as I have some extra $ laying around I may take him up on it. Will post more if I take that road...