Memphis 16-mc1000d

[807tubenut]

Need to know what and where ALL to-220 package parts go inside this amp. Here is the list




D55
D56
D57
D58

Q17
Q19
Q20
Q21
Q22
Q23
Q24


Q211
Q212
Q213
Q214
Q215
Q216


Q251
Q252
Q253
Q254
Q255
Q256


If anyone has a schematic for this amp, Id be interested in compensating the provider.

 

[Perry Babin]

See attached. What do you need the schematic diagram for? I don't have one but I may be able to tell you what you need to know.

 

[807tubenut]

As a EE by trade, I was interested in cloning these amps, for my own sinister reasons, mainly because I want to/can.

Just saves me time from stripping a board down, and REing the circuit.

Just for future reference.


D55 = YG225N2
D56 = YG225C2
D57 = YG225C2
D58 = YG225N2

Q16 = IRF3205
Q17 = IRF3205
Q19 = IRF3205
Q20 = IRF3205
Q21 = IRF3205
Q22 = IRF3205
Q23 = IRF3205
Q24 = IRF3205


Q211 = IRF9640
Q212 = IRF9640
Q213 = IRF9640
Q214 = IRF9640
Q215 = IRF640
Q216 = IRF640


Q251 = IRF9640
Q252 = IRF9640
Q253 = IRF9640
Q254 = IRF9640
Q255 = IRF640
Q256 = IRF640



Thanks Perry, hope I can help you out some day, you give so much and ask so little 🙂

 

[Perry Babin]

The JBL BP1200.1 uses the same class D section. Email me if you want it.

babin_perry@yahoo.com

There are 8 3205s.

 

[807tubenut]

corrected, and email sent.


Interesting, the JBL amp states it's giving 1200w into 2ohms, where this Memphis realizes it's final power @ 1ohm, same wattage, that's marketing for ya.

 

[807tubenut]

Got the new smps fets in today, powered the front-end up, with the outputs and driver cards removed, idle was 1.5amps, Voltage was quite sufficient, and nothing overheated, ill be rebuilding the driver cards, as I found both to have a few cold joints, and the gate drivers shorted. New parts get here next week, Hope I have time to get to the xtant 300.1, and the hifonics TXI7508 sitting on the shelf. http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=280597339033&ssPageName=STRK:MEWNX:IT

 

[807tubenut]

Got it back up and running, idle with no audio is 1.4amps, after the relay closes, all is well, minus this crazy high pitch squeal, some times it fades out, and wont come back for 10~15mins, then once again, right back to the noise! the trimmer's don't change the sound, no matter the position, removed all the caps and tested them for leakage, none detected by me, but there is a cap, in front of the audio driver card (the card with the defaced IC's) that if I touch the body of it, the squeal goes through the roof, replaced it with a really nice rubycon black gate, same deal..


Perry, you ever seen this? I figure it has to be a ground, or lack there of.

 

[Perry Babin]

A squeal that's produced at the preamp level sometimes indicates that there's a bad connection on one of the components in the crossover circuit. Does moving the switches and pots through their entire range affect the noise?

 

[807tubenut]

Moving the pot's, does not change anything, except the gain, and it just makes it louder 🙂


I have good +-15v on the op-amp's, and replaced all the older electrolytic caps.

 

[Perry Babin]

Do you have a scope?

 

[ComputerJLT]

my memphis ST1500D has a high pitched squel also; on the scope its a triangle wave.
I just assumed it was a class D and they're noisy and subs will never be able to make that very low voltage noise audible

 

[Perry Babin]

The residual from the carrier isn't generally audible since it's at 80kHz+ in most amps.

 

[807tubenut]

Do you have a scope?

Yes I have a scope.

 

[Perry Babin]

Post a photo of the output when the noise is present (preferably when the noise is loud). Include the scope's timebase and vertical amplifier settings.

 

[807tubenut]

10/4


As soon as I get back to that amp 🙂

 

[807tubenut]

The issue was the thermal relay, I forgot to put the little condom back on it, b4 I tightened down the clamp 🙂