Tan Music Man

[ToneMerc]

One of my few MM power supply builds

http://ampgarage.com/forum/viewtopic.php?f=4&t=18960

TM

[martin manning]

What is the OT primary impedance used with these 700V plate/350V screen amps?

[Aaron]

BTW!
I think this just might be the Ultrasound Music man
Low plate Skyliner set up for 34's with correct mounting studs.

Tony

Thanks for these pics Tony.

This amp has 25uf on V1 cathodes, I wonder if there are any other ODS with this?

Thanks,
Aaron

[Aaron]

Thanks for the pictures Tony.

You mention using Musicman iron for the D style amps, how does the build sound different with this transformer set.

Hi Mark,
I don't know if you remember my Singer-Land, but it has transformers from an old Fender PS-160. Amp has 700v on the plates with KT88's, and it is LOUD!

Thanks,
Aaron

[pompeiisneaks]

Mark
Yeah!.I was just pointing out where the Stby was for Charlie..I don't know that anyone has yet to draw up an accurate MM PS for an ODS yet.If anyone wants to take a whack at it MM Dropper.jpg

I'd take a whack at it if I knew what you meant by the MM PS, is that the one people call the 'precision power supply'? Where it uses radial instead of axial caps etc?

~Phil

[pompeiisneaks]

Nevermind, was just re-reading, the Music Man version. I'll see if I can find time to look over those pics and come up with something that makes sense.

~Phil

[pompeiisneaks]

And to continue with my rambling, I see you have one earlier talbany? Is that one wrong, or you just want one done in some more formal format like visio or express sch? I can do either or both.

~Phil

[talbany]

BTW!
I think this just might be the Ultrasound Music man
Low plate Skyliner set up for 34's with correct mounting studs.

Tony

Thanks for these pics Tony.

This amp has 25uf on V1 cathodes, I wonder if there are any other ODS with this?

Thanks,
Aaron

Aaron. Not doubting you but how do you know the Ultra has 25 uF on the plates?. No I have never seen or heard of an ODS with anything higher than 10uF

Tony

[talbany]

What is the OT primary impedance used with these 700V plate/350V screen amps?

Martin. Stock MM iron says 5.5K AFAIK..The MM amps had both Hi and low power so I am not sure how they came up with that number..I would try to stay above 4K7

Tony

[talbany]

And to continue with my rambling, I see you have one earlier talbany? Is that one wrong, or you just want one done in some more formal format like visio or express sch? I can do either or both.

~Phil

Phil
The schem I posted needs some tweaking!
To me, it looks like the plates and screen supply's are OK.
Instead of the 2x 22k 10w resistors, Dumble used 40K 10w which gets tied to the plate supply!
The screen/choke is a separate branch which comes off the voltage divider to get exactly half the plate supply.
The 22k PI supply should give you slightly lower voltages on the low plate amps!
For the high plate amps I have seen him use a 12K dropper instead for slightly higher voltages. Unfortunately, I cannot see what value is in the Ultra amp. Here is a shot of 192 a high plate Skyliner which has a 12 K dropper!.So I would make a note on this on the schem since he used both.
Go ahead and make a schematic.If I get a chance this weekend I want to pull an old layout and update it to MM specs and a schematic of this to go with it would be cool!

Dumble used MM transformers in both Classic and Precision Power supplies

12k Dropper.jpg

!

BTW.Guys! Don't get carried away with the 700V on the plates You are not really going to notice a big volume or headroom boost here.The main difference is a more forward open sounding midrange/ quality of breakup and touch sensitivity..That's it
Tony

[martin manning]

What is the OT primary impedance used with these 700V plate/350V screen amps?

Stock MM iron says 5.5K AFAIK..The MM amps had both Hi and low power so I am not sure how they came up with that number..I would try to stay above 4K7.

Thanks, that must be for 4x 6L6, yes?

[talbany]

What is the OT primary impedance used with these 700V plate/350V screen amps?

Stock MM iron says 5.5K AFAIK..The MM amps had both Hi and low power so I am not sure how they came up with that number..I would try to stay above 4K7.

That must be for 4x 6L6, yes?

I don't know,good question!. I am thinking this is for 34's since I don't know of many 6L6's that can handle that high a plate voltage. Most older MM's came stock with Sylvania or Amperex 6Ca7's I think those were rated 800V on screens
Martin maybe you can run the load lines for us for both tubes.That would be really helpful!!
Thanks!
Tony

[talbany]

Hey I found the 200-130 specs.


200-130Primary 120v

High Voltage Sec #1 Sil Voltage Doubler (F.W.) (2) 100mfd

Brn- R/Y 710vdc @ .100a, 660vdc @ .275a

Red- R/Y 440vdc@.275a

Low Voltage Sec #2 org - yel- org

Sil. Bridge (2) 150 mfd cap + - 42 V 0A 60V CT @ .1 RMS

Filaments (2) 6.3V @ 6 A grn- grn/yel

Tony

[Aaron]

Aaron. Not doubting you but how do you know the Ultra has 25 uF on the plates?. No I have never seen or heard of an ODS with anything higher than 10uF

Tony

I have this pic but didn’t know what amp it was from. Looks like it says 25MFD.
Plus the physical size of them look 3 times bigger than V2’s.

Thanks,
Aaron

[talbany]

Cool!
Thanks!
Also do you have any more shots of the amp. Preferably of the front -stack.
I wonder what the Drive and OD mastr value are?

BTW.If this is the Ultrasound amp I heard this amp now resides in Russia

Tony