Ive rescued this amp from the recyclers,to start with it didn't have any bass on the left channel but since Ive cleaned the pots I don't have any bass at all now. I took the volume pot apart and it looked OK but I didn't take the bass pot apart because it has 6 pins coming out of it as opposed to the normal 3 pins and I have no idea if I can put it back together again?Its been sprayed with Deoxit though. I cant find anything obviously wrong with this amp but if by any chance anyone knows what I should look for I'm all ears.Ive got the service manual!
I have since checked the voltages and everything is OK except for the volume circuit IC602 + IC603 they are getting the right voltages but the pin outs are reading wrong? they are logic flip flops,can they be reset or something or do I install new ones? I would like to know why they have failed though.Its hard to get any info on these amps Ive tried AK as well but no luck there either? P.S.Now I can just hear music faintly when Ive got the amp at full volume.
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IC602 &603 are CMOS logic chips that form part of the digital volume controller circuit and output to the display and digital volume controller section. There is no "voltage" to check there as outputs will be in the form of a digital pulse stream.
The point is that the amp. was largely working, it seems, before you messed with the tone controls. These (VR401,402) and the balance control are the only conventional, analog controls and the six leads are required for a stereo pot. You can't simply disassemble pots like these without needing some very careful rebuilding to get them back together. I suggest replacement rather than fiddling but your problem was a lack of bass in only one channel? Perhaps the place to look is in the super bass section but this is not going to be solved in a simple procession like analog amplifiers you see here. Perhaps a bit of study of how this old surround sound processing system and its individual chips perform their functions, will be required before digging in the works again. The block diagram helps to understand the individual functions but you still need to understand digital audio control systems (not digital audio per se) to get a useful working knowledge. This may be a long journey.
Surround sound system systems were popular for a few years i9n the 1990's when HT amplifiers were being introduced at initially unaffordable costs, with their Dolby/DBX processing, so it won't be an easy search for detailed information on these stopgap sound systems, sorry to say.
The point is that the amp. was largely working, it seems, before you messed with the tone controls. These (VR401,402) and the balance control are the only conventional, analog controls and the six leads are required for a stereo pot. You can't simply disassemble pots like these without needing some very careful rebuilding to get them back together. I suggest replacement rather than fiddling but your problem was a lack of bass in only one channel? Perhaps the place to look is in the super bass section but this is not going to be solved in a simple procession like analog amplifiers you see here. Perhaps a bit of study of how this old surround sound processing system and its individual chips perform their functions, will be required before digging in the works again. The block diagram helps to understand the individual functions but you still need to understand digital audio control systems (not digital audio per se) to get a useful working knowledge. This may be a long journey.
Surround sound system systems were popular for a few years i9n the 1990's when HT amplifiers were being introduced at initially unaffordable costs, with their Dolby/DBX processing, so it won't be an easy search for detailed information on these stopgap sound systems, sorry to say.
I replaced the flip flops and when I was putting the amp together to test it I thought I might try the shorting pins LOL yes I hadn't put them back in and I was only getting sound from the pre-amp I had some Sennheiser HD570 headphones on and my ears are still ringing from the blast.The bass is OK now. I suppose Ill never know what was wrong because I changed a few resistors that were out of tolerance and about 4/5 electros,reflowing solder joints ect... Thanks for taking the time to help me,it seems that when someone else is trying to nut it out as well good things happen. I'm surprised at how good this amp sounds! really.
Nice going - 'Most likely corroded or misaligned shorting pin/socket - assuming they are the prone ones, on the rear panel. There are interconnect leads between boards that can give trouble between analog sections too. It was well to replace caps that look aged, bulged or otherwise sus. because if anything fails on this amp, it will almost certainly be the end because the protection system may be at risk too. This is a complex design, even with the high degree of integration.
It seems those Technics Hybirid power amps, as used in the SUX 950, are still much in demand for their sound quality. Hold on to it and take care; it may worth much more than scrap value.
It seems those Technics Hybirid power amps, as used in the SUX 950, are still much in demand for their sound quality. Hold on to it and take care; it may worth much more than scrap value.
Ive found that it depends on the speakers that are used with it on how good it sounds. In the short time Ive had it going Ive tried some Pioneer and Omni bookshelf speakers and JBL TLX6 and DCM QED 1A loudspeakers.They all sound great with this amp in their own way,source is 320 bit MP3 computer files thru a Muse mini DAC, I think people have underestimated these hybrids this one sounds great and that's what its all about for me.The sound.Its not going to knock my Sansui AU11000 off its perch,I love that thing Ha! Ill pass the Technics along to someone who can appreciate it.
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