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

ADA Preamps => Original MP-1 => Topic started by: Chip Roberts on October 07, 2017, 01:31:07 PM

Title: "New" MP1 here!
Post by: Chip Roberts on October 07, 2017, 01:31:07 PM
A week or so ago, my first MP1 went to the Great Rig in the Sky.  Naturally, I bought another one and it arrived today! 

EPROM is 1.38
Line selector switch on the top (if someone could explain what this is/what it's used for I would appreciate it)
Rev D assembly 780002
1988 production year?
Of all things...JACKSON 12AX7s
Title: Re: "New" MP1 here!
Post by: Kim on October 07, 2017, 02:41:34 PM
Cool beans!   :thumb-up:

The switch on top is for the early version MP-1.  It allows the user to select between a Line Level and Instrument Level.  In general, if you were to plug the MP-1 Output into the Input of a regular guitar amp head or combo, select Instrument Level.   If plugging into a proper poweramp you'd likely want Line Level.   The later MP-1s eliminated this switch and just made them at Line Level.   

This switch gets dirty over time and could cause some issues.  Not too hard to replace though.  I even did a Switch Mod document to relocate the switch to the rear panel for the ones who like the easier access to the switch. 
http://adadepot.com/mods/ADA_MP-1_Level_Switch_Mod.pdf (http://adadepot.com/mods/ADA_MP-1_Level_Switch_Mod.pdf)

Jackson never made any tubes.  Neither did Mesa, Fender, or Groove Tubes.  There's only like 4 or maybe 5 actual tube manufacturers left in the world today and all the rest are rebranded tubes from those same factories......
Title: Re: "New" MP1 here!
Post by: Chip Roberts on October 07, 2017, 03:59:11 PM

Jackson never made any tubes.  Neither did Mesa, Fender, or Groove Tubes.  There's only like 4 or maybe 5 actual tube manufacturers left in the world today and all the rest are rebranded tubes from those same factories......

Oh?

Title: Re: "New" MP1 here!
Post by: Kim on October 08, 2017, 12:21:32 PM
That's a rebranded tube, Chip.   Meaning that it was manufactured in an actual tube factory and sold in lots to other NON-tube-manufacturers and relabelled as their own.   Many times you can still see the original faded, partially rubbed off printing on the tube as well as the new printing.  Take one of those suckers out and examaine it closely; hold it up to the light and see if you can still see the original printing.  I have some vintage 1962-63 Wurlitzer 12ax7 tubes lying about that are even labelled as "Made for Wurlitzer by G.E."
So yes, they are Wurlitzer tubes.  No, Wurlitzer did not make them.

https://en.wikipedia.org/wiki/12AX7
"As of 2012 the 12AX7 was made in various versions by two factories in Russia (Winged C, formerly Svetlana, and New Sensor, which produces tubes under the Sovtek, Electro-Harmonix, Svetlana, Tung-Sol, and other brands for which the firm has acquired trademark rights), one in China (Shuguang), and one in Slovakia (JJ Electronic)....."

The one major U.S. tube manufacturer (RCA/General Electric) shut down in 1986 and likely stopped producing the tubes themselves as early as 1976-78.

Mullard had a handful of factories in Europe, and "Philips continued to use the brand name 'Mullard' in the UK until 1988. Mullard Research Laboratories in Redhill, Surrey then became Philips Research Laboratories. As of 2007, the Mullard brand has been revived by Sovtek, producing a variant of the ECC83 and EL34..."  https://en.wikipedia.org/wiki/Mullard

Again, no tubes were actually manufactured by Groove Tubes, Mesa, Fender, Wurlitzer, or even Jackson.  Feel free to contact any of these companies to inquire where they "make" their tubes.  ;)  Maybe ask for a tour of such factories as well?  :lol:

Why rebrand things?  There's plenty of reasons, mostly due to availability and supply (or lack of), overall costs, warranties, etc. 
I can tell you this:  about 12 years ago I worked in a factory that made wiring harnesses for several various big-name manufacturers.  Besides the wiring harnesses that we made in-house, every week or so a truck also showed up and dropped off about a hundred boxes of wiring harnesses from some other factory in China.  These boxes were unpacked, sorted, and all "Made in China" stickers and designations were removed.  These very same wires were then reaffixed with "Made in USA" stickers and labels, reboxed and shipped out as our own.  WTF!!!  I did not ask anyone in charge why this was happeneing, and the ladies doing the actual work didn't seem bothered by it either. :dunno:  Just a paycheck. 
Title: Re: "New" MP1 here!
Post by: MarshallJMP on October 09, 2017, 03:45:05 AM
That "jackson" tube is actually a rebranded chinese tube.

As for the topswitch it only change the output level, not the input like some people might think.
Title: Re: "New" MP1 here!
Post by: Chip Roberts on October 09, 2017, 11:34:14 AM
Kim, that's actually really interesting.  I wonder who/where produced my "Jackson" tubes then?  As for the MP1 itself, it's in SUPER good condition.  Ultra clean in the back, and apparently my dead one had a broken volume pot which is what gave me that horrible hissy sound if I dialed it past midnight.
Title: Re: "New" MP1 here!
Post by: MarshallJMP on October 09, 2017, 12:42:55 PM
They are made in China by shuguang.
Title: Re: "New" MP1 here!
Post by: Chip Roberts on October 11, 2017, 09:50:10 AM

The switch on top is for the early version MP-1.  It allows the user to select between a Line Level and Instrument Level.  In general, if you were to plug the MP-1 Output into the Input of a regular guitar amp head or combo, select Instrument Level.   If plugging into a proper poweramp you'd likely want Line Level.   The later MP-1s eliminated this switch and just made them at Line Level.   

Follow-up question; if I'm plugging it directly into the input of my Midiverb, would I want it at Line Level or at Instrument Level?
Title: Re: "New" MP1 here!
Post by: MarshallJMP on October 11, 2017, 12:01:06 PM
Line level is always better.
Title: Re: "New" MP1 here!
Post by: rnolan on October 12, 2017, 01:23:11 AM
Line level is always better.
+1  :thumb-up:
Title: Re: "New" MP1 here!
Post by: Chip Roberts on October 12, 2017, 10:50:06 AM
Thanks for your help, dudes.  Broke this out at Princeology rehearsal the other night and it screamed pretty hard!  I can't believe the shape it's in considering what I paid for it; $240 USD after shipping and it's an early model!
Title: Re: "New" MP1 here!
Post by: Kim on October 12, 2017, 01:47:09 PM
SuhWEET!   The early models still in really good shape are getting harder to find.  Heck, any MP-1 still in good shape these days is starting to get rare.