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[RobbHell]

MJMP Please give me your thoughts on this. Everyone is welcome to chime in as well.
I've been going over a lot of Peavey schematics here are some ideas I have do a pretty good mock up for a 5150 tube stage.

R6 (220k) C15 (1uf) R24(jumper) R25 (1.8k)  C10 (.022uf)   C11 ( 470pf or 2.2m resistor?) R20,R21 (470k) C14(1uf) R22 (1.8k) C9 (.022uf) R19 (470k) R18 (1M) R15 (39k) C7 (none) C3 (.022uf) C4(jumper) R13 (220k) R14  (330k) then Piggy back a (.001 uf) cap over R14.  R2 (220k) R16 (1.8k) C6 (1uf) C5 (.022uf).

R7,R23 (47k)  C12,C16 (1uf or .47 uf)

Now that is almost the exact layout for the first four tube stages of the Original 5150 minus its extra gain stages. I think this would be a great revision of MOD3 and give users more of less exactly a 5150 tube board. I'm also thinking of relocating the H wire to the 7th pin of V1b like in the 3.666.  The 3.666 is a pretty damn good since we only have four gain stages its a great copy of the first four stages of the Recto minus the leads stages.

Appreciate your feed back and thoughts.

[RobbHell]

Does anyone have the specs for the voltage going into the Anode Triode on a 5150? On the Mesa's and Soldano's  its very high voltage.

[George I.]

Does anyone have the specs for the voltage going into the Anode Triode on a 5150? On the Mesa's and Soldano's  its very high voltage.

my 5150 script logo measures as follows (give or take 10-15 DCvolts depending on whats running in the house, so take it with a +/- 20 or so!)

plate volts at pin 3 of power tube - 495 (i've seen it as high as 515 though)

preamp main tone tubes at the plates measure DC volts as follows:

v1a (first gain stage)  160dc
v1b (second gain stage) 217

v2a  -295
v2b - 168

v5a - 248
v5b - 189

i assume you dont need the fx loop or PI tube readings as there wouldnt be any real way to implement these in the ada mp1 mod.

v3 is the effects loop tube
v4 is the phase inverter

[RobbHell]

A MDRT would help but yea I noticed in most of the schematics  I was reading between Peavey/Mesa/Soldano  the plate voltage was usually 215-395+ .

[RobbHell]

Would anyone be interested in this? Was hoping for a little more feed back.

[gb]

Always loved the 5150 sound. I have an ada mp1 with the mod3? Soldano/5150 mod?. Its ok. But if you want test subjects to try the above lol im happy to use that ada.

[RobbHell]

The Mod 3.1 uses (2) 470k  resistors and a 1M for increased gain compared to the Mod3.

I've always felt Mod3 was a bit unfinished. That's where the listed above changes come into play. My spare Tube boards are in storage or I would have built it.
I feel these refinements will surely give MOD3 that 5150 Block Letter sound but cleaner.

[gb]

The Mod 3.1 uses (2) 470k  resistors and a 1M for increased gain compared to the Mod3.

I've always felt Mod3 was a bit unfinished. That's where the listed above changes come into play. My spare Tube boards are in storage or I would have built it.
I feel these refinements will surely give MOD3 that 5150 Block Letter sound but cleaner.

im not using a mdrt powersupply but for some reason I felt my stock mp1 sounded better than the mod3. The mod3 sounded brighter and the eq didnt behave like my stock. My mod3 sounds like a low gain soldano. Thats why I prefer my soldano preamp most of the time cause its high gain.

So i just need to make the changes above to the board. I dont have tube boards unfortunately so ill just use the existing

[RobbHell]

The Stock Gain Mod isn't bad but nothing to get excited over.The sound issues your describing is because only the Last Gain stage is Modified with too different tone caps. I'm not here to.bash but Mod3 sounds like shit because its a Half assed and unfinished mod.
Why the first two stages were left untouched is a Tard move and lazy honestly.
That's why felt it was time to give back my time and research into updating... Hell I use combo of mods on my ADA. Yes I felt ADA stock with a Eq sounded better than MOD3.
I just drove me nuts to read Mod3 schematics.I appreciate the work that went into developing the Mods but honestly the First three Mods are a step backwards for ADA users. Lets fix this now lol.

[RobbHell]

An MDRT would be a must to take full advantage of the Mod. The Slo/5150/RECTO  all have high voltage well above the MP1s stock 180v.
I'm rather surprised MJMP hasn't read or replied to this post.

[gb]

Ill order one from mjmp

[RobbHell]

Get his Noise mod kit. You'll be glad you. With more gain there's always more noise. But it can be fixed.

[Systematic Chaos]

5 or so years ago I had MJMP do me a customized Mod3.1 incl the MDRT to one of my MP-1. It actually addressed some of the points/parts as mentioned above (incl H-wire). In addition, I altered some of the coupling caps to enhance/widen the bass response some, as in the orig MP-1 EQ that is a pretty narrow freq.
To really make that SLO/5150 thing shine, the MP-1 has to be paired with a 6L6 poweramp.
I hooked mine up with an old Boogie Fifty/Fifty and the result was a SLO100 on steroids with creamy singing leads and bold rhythms. Palm mutes were spot-on tight and hi-gain open chords still had that note separation.
Dunno about the exact specs/parts anymore though....just that I used Orange Drop 716P as they (imho) sounded a tad bit more "breathing"

[gb]

I just plugged my mod3 into my vht kt88 and cranked it and geezus it sounded awsome. I retract my comment before lop however its missing something. I wonder how close the mod3.1 is on mjmp website is in comparison to above changes. Im reluctant to change my board now after hearing it again out of storage.  If the specific mods are on the tube board I might buy another from mjmp perhaps.

and perform the noise mod however I had no noise at all on this unit. I was impressed to be honest.

It was loud articulate. . But feel it could he better.

[RobbHell]

I tend to notice Clean Tube driven hard has that thick Slo sound not Dist Tube.  Relocating the H wire really helps A Lot!

Mod3 lacked gain for me to consider it 5150... SLO medium gain yes.