ADA Depot - A Forum To Support Users of ADA Amplification Gear

ADA Preamps => Original MP-1 => Topic started by: mrguitar on November 08, 2018, 11:11:14 AM

Title: A couple questions around this craigslist MP-1 find
Post by: mrguitar on November 08, 2018, 11:11:14 AM
Hey so I've always regretted getting rid of my MP-1, and I couldn't resist picking one up from craigslist for $100 a couple weeks ago. The unit is pretty banged up, and had the standard problems of dirty pots, jacks, and dead battery. A little contact cleaner and ~5 min w/ the soldering iron and it's working pretty well, but there are a couple things that seem fishy.

here's a shot before I replaced the battery w/ a proper tray: https://photos.app.goo.gl/2vq9sJEWaKK1a4w18

1) Can anyone tell if this is an original transformer? https://photos.app.goo.gl/o6uowZ615ewB4BSL7
I couldn't get any details from the seller, but It's really odd how only 1 side is attached and the clips is bent. I can think of several scenarios that could lead to this, but from looking at pictures online I'm unable to tell if this is the original one. (btw, only mounting one side will cause crazy vibrations, don't do this. I'm glad it was an easy fix)

2) I typically just use the metal/open switchcraft jacks, but since I haven't done a lot of work on rack gear i wanted to see if anyone recommends using the original style of jacks instead. If so specific part numbers would help me source them.

3) I'm missing 5-10 of the screws for the top & bottom lids. Does anyone know the size and where to source these?

Anyway, now that it saves presets, and sounds great, I'll probably upgrade the firmware chip, as it's 1.38, and swap out most of the jacks. I'm pretty happy with the sound so far, and I think I'll be in good shape for a while with these changes. I would also love to know if there are other things you all think I'm leaving out.

 Thanks in advance and for keeping this community alive! I love this stuff.
Cheers,
Ben
Title: Re: A couple questions around this craigslist MP-1 find
Post by: MarshallJMP on November 09, 2018, 08:52:27 AM
1 tranny is original that screw isn't  ;D

2 look for the rear jack mod on the forum

3 size is 4-40 x 1/4
Title: Re: A couple questions around this craigslist MP-1 find
Post by: rnolan on November 09, 2018, 07:07:50 PM
Hey Ben, welcome to the depot , you can get most of the bits you need from MJMP (http://www.marshalljmpmodshop.net/miscellaneous_parts_and_replacement_tubes.htm).  The last EPROM revision for MP1 is v2.01.  He also has the rear jack mod parts pre wired.  This changes the front jack to a non-pcb normal style which is how the later (no top switch) MP1s are.  He also has a bunch of the jacks you need if you want to change them out.Depending how much use the tubes have had it's probably time for some new ones and the noise mod (replace a bunch of caps) is a good idea.
Title: Re: A couple questions around this craigslist MP-1 find
Post by: mrguitar on November 10, 2018, 01:36:39 PM
rnolan & MarshalJMP, thanks for the details!

Good to know this is the original transformer. I needed to properly attachit because it was vibrating like crazy with only one lug attached <facepalm> when I got it. All I had were some mother board studs and screws. They seem to work fine, for now.

Cool I'll figureout which parts I need and send a PM.

Again, seriously thanks for keeping this alive. I've been having a blast with this unit and I forgot how good these sound.
Title: Re: A couple questions around this craigslist MP-1 find
Post by: rnolan on November 12, 2018, 01:10:58 AM
Hey Ben, no worries  :thumb-up: happy to help.  Glad you are re-discovering how great these preamps are  :whoohoo!: