Hey guys,
I was given this SS Reference 604x. I plan on trying to integrate this amp into my current personal car stereo, where I have a SS MC140x currently running a pair of door components. The MC140x is only 35x4 and runs very very hot sometimes, where this 604x is 75x4 but has 3 times the number of output componants than my MC140x.
What I'd like to do with this SS 604x, is run both the door 6.5 and tweeters directly to each individual channel of this 604x. The thing is this amp does not have a super-high pass crossover array high enough to cross over for the tweets.
Is there any way I can replace/redo the crossove network on 2 channel from this amp, so that it can adjust between 1000~5000hz?
In the meantime, this amp has some cosmetic repair issues which I intend to address. There are two chokes and two caps needing better attention in the power supply section. I'll need new cores, copper wire, and rail caps. The coils were obviously shorting to the back cover of the amp.
The PS fets are in tact which is good news, but it appears all the rectifiers had been replaced previously.
Large, R923 runs a lot hotter than R924, and R928 runs super-hot.
Channels 1&2 have replacement output transistors and source resistors. All four channels have one 0.22ohm source resistor, where I believe they should be 0.27ohm.
Channels 1&2:
Channels 3&4:
The amp powers and plays, but channel #1 has what I want to call notch distortion noticable on the scope on the positive rising edge of the waveform. The notch is only noticable with a load.
Thanks for any help
I was given this SS Reference 604x. I plan on trying to integrate this amp into my current personal car stereo, where I have a SS MC140x currently running a pair of door components. The MC140x is only 35x4 and runs very very hot sometimes, where this 604x is 75x4 but has 3 times the number of output componants than my MC140x.
What I'd like to do with this SS 604x, is run both the door 6.5 and tweeters directly to each individual channel of this 604x. The thing is this amp does not have a super-high pass crossover array high enough to cross over for the tweets.
Is there any way I can replace/redo the crossove network on 2 channel from this amp, so that it can adjust between 1000~5000hz?
In the meantime, this amp has some cosmetic repair issues which I intend to address. There are two chokes and two caps needing better attention in the power supply section. I'll need new cores, copper wire, and rail caps. The coils were obviously shorting to the back cover of the amp.
The PS fets are in tact which is good news, but it appears all the rectifiers had been replaced previously.
Large, R923 runs a lot hotter than R924, and R928 runs super-hot.
Channels 1&2 have replacement output transistors and source resistors. All four channels have one 0.22ohm source resistor, where I believe they should be 0.27ohm.
Channels 1&2:
Channels 3&4:
The amp powers and plays, but channel #1 has what I want to call notch distortion noticable on the scope on the positive rising edge of the waveform. The notch is only noticable with a load.
Thanks for any help
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I was correct in stating: High Current mode draws excessivly hence why the previous repairer glued the switch rom entering that mode. You can see the white glue in the photo above. High Power (Voltage) mode works fine. I did not desolder anything yet. I didnt remove the board from the sync either.
Im actually still debating on fixing this one still with all gremlins showing. I owe the owner a bit of money for this amp which I was fine in paying before, but now that its not looking as good as I thought it would be, I may be out to spend too much to fix for my personal usage.
None-the-less I'm going to give it a fair shot. As for the coils, I'm thinking of just clipping them right off the board since the copper's enamel is discolored, black, and chipping off - plus the core is also discolored. Clipping them would save me from removing the board off the sync which i hate to do to these soundstream amps.
Im actually still debating on fixing this one still with all gremlins showing. I owe the owner a bit of money for this amp which I was fine in paying before, but now that its not looking as good as I thought it would be, I may be out to spend too much to fix for my personal usage.
None-the-less I'm going to give it a fair shot. As for the coils, I'm thinking of just clipping them right off the board since the copper's enamel is discolored, black, and chipping off - plus the core is also discolored. Clipping them would save me from removing the board off the sync which i hate to do to these soundstream amps.
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I'm not even understanding why those 80v1500uf caps were even installed. I removed them and the coils and found no marker or denomentation for caps. In looking at a Reference 302 and Rubicon 702, this amp appears to only require 4 rail caps 50v 1000uF.
The twin inductors are both really nasty looking. I also took them off for a new perspective.
With both these pieces out, the amp will still not enter High-Current mode. High Power mode again seems OK.
The twin inductors are both really nasty looking. I also took them off for a new perspective.
With both these pieces out, the amp will still not enter High-Current mode. High Power mode again seems OK.
perhaps it was an attempt to band-aid the rail voltage condition. i don't have any schematics for this amp, or any with the manual hp/hc switch. what i can tell you is that the auto switching ones i have use the tlo72 to change the amount of (+) rail voltage that the 3524 sees on pin1, similarly to the thermal switch, which also increases the signal when triggered, so that the ic will regulate the ps to put out lower voltage. i would imagine that the switch is either not making contact, so that the ic is not seeing any (+) rail signal, or there is a bad inline resistor, or transistor. then again, if it was band-aided in this way, and the hp side of the switch is bad, and jumpered, then switching it to hc, if good, would parallel the circuits, but i would think that would let it regulate to a lower rail voltage, if good. also, i do not see how that second ic is working in the circuit, nor how the first one is "wired" in or if it is the same/similar
Thanks guys,
Im starting to regain some sort of hope in fixing this amp. I'll unfortunately need to get a new Current/Power switch probably once I work all the bugs out. Apparently in High-Current mode since its drawing hard - the switch contacts are bad off. The formal owner dismantled the switch for cleaning/fixing and now it sits very loose on the board. it needs to be replaced so hoping J&R has one or maybe I can find something similar from Mouser, or perhaps use some kind of high-current jumper or even a fusible link connection, like with ~10A car fuses? For now I'll hard-wire it for High-Current so that I can continue testing/fixing this amp. I shouldnt continue testing HC mode until I get this contact problem solved.
Avert; Thanks for emailing me the schematic
Once I have that I should be able to figure out replacement inductors. I pulled the 2 large out-of-place caps from the first photo, and now noticed the amp has enormous amounts of noise in the positive and negative rail voltage, almost like +-1v saw tooth.
Also, any clues on why channel 1 has the notch distortion? Is the bias circuit the T0-92 transistor wedged under the pcb the suspect?
How do I make sure the outputs are matching? I thought I read that somewhere with checking voltages but wasnt sure.
Im starting to regain some sort of hope in fixing this amp. I'll unfortunately need to get a new Current/Power switch probably once I work all the bugs out. Apparently in High-Current mode since its drawing hard - the switch contacts are bad off. The formal owner dismantled the switch for cleaning/fixing and now it sits very loose on the board. it needs to be replaced so hoping J&R has one or maybe I can find something similar from Mouser, or perhaps use some kind of high-current jumper or even a fusible link connection, like with ~10A car fuses? For now I'll hard-wire it for High-Current so that I can continue testing/fixing this amp. I shouldnt continue testing HC mode until I get this contact problem solved.
Avert; Thanks for emailing me the schematic
Once I have that I should be able to figure out replacement inductors. I pulled the 2 large out-of-place caps from the first photo, and now noticed the amp has enormous amounts of noise in the positive and negative rail voltage, almost like +-1v saw tooth.Also, any clues on why channel 1 has the notch distortion? Is the bias circuit the T0-92 transistor wedged under the pcb the suspect?
How do I make sure the outputs are matching? I thought I read that somewhere with checking voltages but wasnt sure.
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