:wave:Greetings of peace and power from lower Manhattan ! I'm Hymnofotherspheres . It's a pleasure to be a new member , looking forward to meeting everyone and gaining more knowledge about the mp1 . Gear : ADA mp1( original) , Peavey Rock master preamp , Engl 920 stereo power amp , Engl XXL 4/12 stereo cab. Real name's Cliff 8)
Well Hi, and welcome :thumb-up:
Hey
Welcome to the depot.
Hey Cliff, welcome to the depot, nice gear BTW. What revision is your MP1 (should show on boot/power on) firmware ?
Welcome Cliff!
Nice to have ya along
Quote from: rnolan on July 01, 2014, 07:17:39 AM
Hey Cliff, welcome to the depot, nice gear BTW. What revision is your MP1 (should show on boot/power on) firmware ?
. Hi and thanks for all the greetings , this is going to be a very cool experience ! My mp1 has revision 2.01 . I picked it up for 50.00 , thought it needed a new tube transformer but possibly only needs new tubes . The tube / distortion presets don't work , ss/ clean presets are fine .
Quote from: Dante on July 01, 2014, 08:47:54 AM
Welcome Cliff!
Nice to have ya along
Thank you Dante
Did you send me an email for a new tranny?(Cliff)
Cliff hey Dude welcome to the Depot! It's a Awesome place with plenty of Dudes to help out with any issues or questions etc that you might have. Take it easy...Steve :metal:
Hey Cliff, hope it's just new tubes you need, SS wouldn't work if no power but the tubes also need heater filament power (MJMPs territory, possible transformer problem ?). Unusual for tubes just to not work, they tend to degrade (slowly) but generally just sound more shabby (though they can just not work, but both of them ?? and if so why ??).
The 2.01 is the last EPROM upgrade so your on the latest version. If you are going for a new transformer, the MDRT is a good idea, while it's more expensive it's a good and worth while mod (http://www.marshalljmpmodshop.net/miscellaneous_parts_and_replacement_tubes.htm).
Do the tubes light up/glow when you power it on ??, if so there may be a different problem.
It will probably need new tubes though regardless, many choices and good discussion elsewhere on the depot, for MP1 I'd go with low noise high gain JJs (http://www.dougstubes.com/preamp-tubes/12ax7-ecc83-7025/jj-ecc83.html) or short plate Mullards (http://www.dougstubes.com/preamp-tubes/12ax7-ecc83-7025/mullard-cv4004-12ax7.html), the Mullards are a more 3D tube IMHO, but very subjective area tube choice.
Any way for $50 you've bought one of the best tube preamps ever made and definitely worth getting it going.
Cheers Richard
Thank you I have a few JJs around which I'll use for the mp1 as well as the rockmaster . The RM is being moded this week also . I tried new jjs in the mp1 with the same results , ss presets work clean and with effects but no distortion . The self diagnosis function doesn't initialize it after 8 seconds , so there is a problem , I have to switch it on again . I just want to make certain a transformer is what's needed , think I might have my tech look at it before proceeding although I wanted to do it myself if possible . :thumb-up:
Quote from: MarshallJMP on July 02, 2014, 03:44:38 AM
Did you send me an email for a new tranny?(Cliff)
. Not yet Marshall , I'll have my tech take a look at it after I get the rockmaster back .hu
Unfortunately it sounds like issues in the MP1, I'm not convinced it's a transformer issue or you'd have no power at all. Do the tubes light up (glow?), if so, my guess is it's not the tranny (MDRT is still a good idea though). Again more MJMP/Sparker territory :bow: Get your tech to check it out, schematics etc on here to assist. If you want to chase it through yourself (no doubt will need a multimeter), MJMP can talk you through it.
You can check if you have 190Vac on the red connector on the tubeboard.Or if you want to play safe,power off,pull the red connector off the tubeboard and measure the resistance.Should be below 800 ohms.
Quote from: MarshallJMP on July 14, 2014, 05:26:27 AM
You can check if you have 190Vac on the red connector on the tubeboard.Or if you want to play safe,power off,pull the red connector off the tubeboard and measure the resistance.Should be below 800 ohms.
I'll have to check it out . Thank you
Quote from: rnolan on July 13, 2014, 06:35:15 AM
Unfortunately it sounds like issues in the MP1, I'm not convinced it's a transformer issue or you'd have no power at all. Do the tubes light up (glow?), if so, my guess is it's not the tranny (MDRT is still a good idea though). Again more MJMP/Sparker territory :bow: Get your tech to check it out, schematics etc on here to assist. If you want to chase it through yourself (no doubt will need a multimeter), MJMP can talk you through it.
. Thanks , I spoke with him about it this afternoon , he's worked on them in the past so hopefully he can solve the problem . I'll give him the suggestions you guys have offered and I told him about the schematics . The unit works fine when the ss presets are called up , but no functioning distortion presets . I get clean and effected clean only , as I also said I, it must be turned on twice as the self diagnostic does not reinitialize it . Yes the tubes are heating , I put in a new set with the same results , no difference with the tube change .
You can give him my email if he has questions,maybe i can help out.
Quote from: MarshallJMP on July 14, 2014, 05:26:27 AM
You can check if you have 190Vac on the red connector on the tubeboard.Or if you want to play safe,power off,pull the red connector off the tubeboard and measure the resistance.Should be below 800 ohms.
. Marshall , I've not been here for awhile. My tech now has my mp1 , he'll take a look at it this morning . I've given him your contact information as well . Although he's worked on mp1s previously , he'll contact the you if there's a problem he can't solve . Thank you for the assistance .
Ok no problem. :thumb-up: