yamaha P-2200...what to do?

[mrnedrub]

Hi ...l have a yamaha p-220 amp and its been working fine with out a problem on some JBL bins in my garage for the odd party or birthday. Anyway l sold the JBL speaker a year ago and now thought about useing it as a amp for a subwoofer in my home thearter set up. Then l decieded to get a new front from yamaha spares to make it look new and "spiffy". After finding out that this would cost aprox $400 l then thought that l would get a nice 10mm thick alluminium plate and have it milled with nice glass windows for the meters and "spiffy" blue LED with a brushed finish.
So l started to pull it apart and was a little disipointed to see that alot of the parts were .....cheap. Overall the outside look and performance didnt match with what l thought the innards of a pro amp from the makers of yamaha. Maybe its because l have not seen a lot of pro amps and that most of the amps that lve played with have been for domestic hi-fi.
Now lm thinking perhaps l should use the caps.trannie,case/heatsinks and put new amp boards like NX150 from Aussie amplifiers or make it into a leach amp(l think thats how you spell it?) not use the meters on the front or the volume pots and have a plane alluminium front(only on/off and LED) and making a new home hi-fi amp. OR try upgrade as manny parts as l can on the yamaha p-2200 boards , upgrade wires etc and would any of the upgrades make any diference anyway?

If any one would like to add any coments or ideas l would be very gratefull. Thanks for being patient with the long post!!

[anatech]

Hi mrnedrub,
Gee, I used to service those under warranty, and out. They are not cheaply built at all! Price an input level control. They even used thermal grease on the power transformer. They are designed to be light weight as many were roaded.

These are very clean amplifiers and reasonably tough. My personal viewpoint is that it would be a crime to do what you are suggesting. Clean it up and treat any new amps with more care.

-Chris

[TomWaits]

I had a P2201 for many years and it was a fantastic sounding amp. I had it opened up a few times and nothing about it seemed cheap to me, infact I thought it was built like a tank. It certainly worked like a tank as I did the DJ thing with it for four or five years. When we parted ways I I sold it for the same price I paid when I picked it up second hand. I really wish I held on to it. It was a kind of reference amp for me as it was the first "big" "nice" sounding PA amp I had. It had the first torroidal transformer I ever saw and I picked it up in 1985/86.

If I had one now I would put some "love" into it and take it to my grave.

Cheers,

Shawn.

[FastEddy]

found this: http://www.ampslab.com/PDF/yamaha_p2201.pdf

If you want to dump it, I'll pay shipping ... he, he, he ...

Yes, you could "put new amp boards like NX150 from Aussie amplifiers" ... but I wouldn't unless the main boards are beyond repair. (FYI: http://3dotaudio.com/ampics.html = worked out very well indeed.)

[TomWaits]

For me that pdf says a lot about the quality Yamaha was packing into their commercial line of products back in the day; it is almost a "101" on basic PA implementation.

The rail voltages are high in these amps like +/_80 VDC so care would be required if using the existing power supply for another drop in replacement. I don't think the NX150 would survive those rails but I have not seen the schematic so perhaps it could be tweaked for the application?

Also the Yamaha is set up for TO3's on the outputs, I believe the NX150 has a different package integrated into the PCB design?

Cheers,

Shawn.

[FastEddy]

"... The rail voltages are high in these amps like +/- 80 VDC so care would be required ..."

Yes indeedee = AA says that voltage may be too much for the NX150, not to be stressed beyond about +/- 68 VDC (as per previous link = Crown rail voltage.) ... FYI: Anthony is very forth coming with modest tech support ( aussieamps@netspace.net.au ). You might take a look at his brand new NX400 Synergy or the NX500NL or even the NX800N. (I am sure the NX800N and NX1000N will handle the +/- 80 VDC heat ... but best to ask him first.)

Also, the TO3 transistors in the Yamaha would or should be bypassed as the NX150,'400, '500, '800 & NX1000N are designed for and include matched sets of power MOSFETs, not "regular" transistors (The MOSFETs can easily be aligned with the Y2200's existing heat sinks, however.)

http://aussieamplifiers.com/power_amps.htm ... I recommend 'em and have two NX150 pre-assembled modules and two AV400 kits and just recently obtained two NX400 Synergy (got a couple of the prototypes, but have not assembled or run any tests as yet.) ... all these modules are priced within a narrow range = ~US$160 to ~US$350, each module plus shipping.

Yes, I have drunk the AA koolaid and I like power MOSFETs a lot = more efficient ( ) plus almost tube like performance and listening quality = plenty of guts on the low end, clean clear high end, smooth transition at clipping ...

.....

All the above long winded discourse being said, I would still suggest that gutting the Yamaha 2200 might be a grevious error. If that puppy still works and works pretty good, why don't you just tweak the caps with some high quality poly goodies, upgrade the wiring if you must and learn to love it! .... That Yamaha design with all those features would be a shame to part with IMOP ... (Do a retro fit of a junk amp, and save the Y2200 for your personal stash.)
...

[anatech]

Hi FastEddy,

(Do a retro fit of a junk amp, and save the Y2200 for your personal stash.)

You had me worried. I'm glad you said that! That P-2200 is actually an advanced design for the time period. Way overkill for sound quality.

They were very good in recording studios.

-Chris

[FastEddy]

" ... That P-2200 is actually an advanced design for the time period. Way overkill for sound quality. ... They were very good in recording studios. ... "

Glad you said that too. I was worried there for a minute that mrnedrub might actually junk it. I would pay him a reasonable amount and shipping just to have one for my personal stash ... way cool, loaded with nice pro-gear features and a well thought out design. I would bet all it really needs is some power supply clean up = better poly caps, etc.

[anatech]

Hi FastEddy,

I would bet all it really needs is some power supply clean up = better poly caps, etc.

That's what I had in mind too.

I would pay him a reasonable amount and shipping just to have one for my personal stash

Nice thought, but shipping would be killer from Oz!

-Chris

[mrnedrub]

Hi , thanks for some great ideas and for replies!! I went to the local sevice center and found some nice spray for cleaning the pcb and this has worked a treat. After looking closer at the board what really concerned me was the amount of resin on the solder joints and on the wires that conect to the T03 to the board.....In regards to the "cheap-ness" this remark was more about the fact that this amp sounded so good to me that l was expecting more inside than l found.
So l was thinking to re-spray/powder coat all pieces semi gloss black , re-wire inside with better grade wire for power/T03/speakers , leave out level controls and re-wire from new RCA/balanced inputs straight to the boards(with good S.Q coax) then finish off with a new 10mm alluminium front with brushed finish(black or silver ?) based roughly on the original(should l use the meters or not?)
Does this sound better? Also when replacing the caps should l relace all caps on board or only some. Can anyone give me ideas as to what brand l could use and still have money left to eat?

Cheers to all and thanks again to those who make this place what it is!!