DC output in Soundstream MC245

[Here-I-Come]

Wow, it amazes me that this thread is still alive and obviously I'm not alone.
I would like to thank everyone who has helped me over the time. The amp is fixed and not a single popping noise (thump) and it's now working great, and what I did was just add an aftermarket relay and glued it onto the PCB 😀

Without everyone's contribution, my SS amp would probably still be sitting on a work bench and become a piece of furniture. So, once again. THANK YOU ALL!!
This site has helped me in a big way, being that i'm half way across the world.

🙂 🙂

I first so Hi, I new here, but not to car audio.

I hate to dig up this old post, but I have a MC245, well 2, one more is on its way. The one I have has the same small turn on pop. I would love to know where this reply was placed on the board and the connection. Planning and old/new school system I that I will be competing with so I can't have the pop or I will loss points. Or is any one has the reply board sale drop me a PM.

I also have a MC140x, 2 D100II, and a D200 (the frist one). Had a MC140, but I just sold it, and I all ready want it back😀.

Thanks for all your help in advance.

 

[Old'n'Cranky]

Grave dig I know 🙂

But I'm wondering if anyone can share the drawing or pdf regarding the extra output relay mentioned here ?

Soundstream MC-245's
At the end of production, Soundstream installed a small relay board

I can send you a picture of the relay board and a PDF of the layout drawing if you are interested.

Failing that I can see two possible options.

1. Drive new relays from the existing relay drive in the sub circuit.
2. Copy the relay drive system from one of their other model amps.

I suspect option 1 will be what I use.
The choice will become obvious once I have the schematic and amp in my possession 🙂

Also, I've noticed photos of the later MC245's with a circuit breaker installed in the sub output line.
Obviously to protect the output transistors.
Can anyone comment on that ?

Thanks all.

 

[Old'n'Cranky]

Just in case anyone out there in the future wants to do something about the turn on/off click/thump on the four main channels of their MC245.
I have done a small modification to mine and post the info here.
I do not know if this is how SS did it.
But it seems the simplest most logical way to me.
Plus it works 😀

I used silicone to mount 2x G6B-2214P-US DC12 Omron Relays (Digi-Key: Z759-ND)
I chose this relay primarily due to their low current draw which should pose no issue for the factory relay drive circuit.

The small bit of veroboard on each relay is to give a larger solder pad and support the weight of the wires and stop the risk of breaking the relay pins.

I put a piece of gaffa tape on the inside of the lid just for extra insurance against shorts in case a relay comes loose.

The power for these two extra relays is taken from the original relay drive circuit.

During my update I re-caped the amp with a mix of elna silmic II, panasonic FC and FR.

Replaced the (old corroded) rca connectors with Chinese CMC clones.
I had to open the rca holes 1mm for them to fit.

Finally I replaced the thermal pads with Keratherm reds from the diyaudio store here 🙂