My HK 930 has worked well for a long time but recently the left channel has gotten very weak. I have to turn the balance control about 3/4 to 7/8 turn to the left to equalize channel volume. I'm not an electronics pro but am willing to take a stab at tracking down the problem if it's not way too involved. Anyone have suggestions?
Thanks!
Thanks!
If the problem is internal, I would first suspect switches, particularly the tape monitor. Switch the speakers to make sure you don't have a bad speaker. Check the integrity of the speaker connections too.
The tape monitor switch is always a potential culprit because all the audio goes through it and it seldom gets exercised, opening the door to creeping corrosion.
The tape monitor switch is always a potential culprit because all the audio goes through it and it seldom gets exercised, opening the door to creeping corrosion.
re: HK 930 weak left channel
Thanks for the suggestion Bob. Sadly, the tape monitor switches are OK so the problem must lie elsewhere.
Fred
Thanks for the suggestion Bob. Sadly, the tape monitor switches are OK so the problem must lie elsewhere.
Fred
The 930 has a pre-out mainamp- in link at the back you can take out the links and wire the left channel pre to the right power amplifer using a phono to phono lead also cross over the right pre to left power this will show if the problem is in the pre or power amp
then you need to take further steps
I have very many Hk in my collection the fault could be any no of things
regards Trevor
then you need to take further steps
I have very many Hk in my collection the fault could be any no of things
regards Trevor
Thanks Trevor...what am I looking for when I re-connect the pre and power amps? I found the links, connected an RCA cable to the pre and power amps as you indicated. Using headphones, I found the right channel still noticeably stronger than the left. I'm not really sure what I'm listening for however? Unfortunately, I'm a newbie at this sort of thing and fear my lack of expertise keeps me from self-diagnosing the problem...
Fred
Fred
you must get a phono to phon lead
pull out the connecting links between the pre-out to power in
then using the phono lead connect the left pre-out to the right poweramp in connect the right preamp out to the left power amp in
if the fault changes sides the fault is in the pre section if it stays the same side its in the power section
the hk of this age have two main problems faulty caps and faulty transistors
do this test first so that we know where the fault is
regards trevor
pull out the connecting links between the pre-out to power in
then using the phono lead connect the left pre-out to the right poweramp in connect the right preamp out to the left power amp in
if the fault changes sides the fault is in the pre section if it stays the same side its in the power section
the hk of this age have two main problems faulty caps and faulty transistors
do this test first so that we know where the fault is
regards trevor
Trevor,
Thanks for walking me through...the fault does change sides so I assume the problem lies in the pre-amp section. Not to abuse your kindness, but can you suggest what I do now to locate the offending component(s)? I can solder fairly well and have done some component replacements on other units so I'm willing to replace bad caps, et al if I know which ones are bad. I just need guidance...Thanks!
Fred
Thanks for walking me through...the fault does change sides so I assume the problem lies in the pre-amp section. Not to abuse your kindness, but can you suggest what I do now to locate the offending component(s)? I can solder fairly well and have done some component replacements on other units so I'm willing to replace bad caps, et al if I know which ones are bad. I just need guidance...Thanks!
Fred
Trevor,
Stop the presses! I found the problem... blown left channel speaker fuse! So obvious I shjould have checked it first! Thanks again for all your help!
Fred
Stop the presses! I found the problem... blown left channel speaker fuse! So obvious I shjould have checked it first! Thanks again for all your help!
Fred
Well I am pleased well done but the fault should not have changed sides!
Yep HK fit a resistor across the Ls fuse this then allows the channel to run at a very reduced level but will not allow enough current through to damage your spk should there be a fault.
Great equipment that range
best regards Trev
Yep HK fit a resistor across the Ls fuse this then allows the channel to run at a very reduced level but will not allow enough current through to damage your spk should there be a fault.
Great equipment that range
best regards Trev
hk 930 channel weak
I know this is an old thread but I’ll try my luck anyways….I have a HK 930 with a weak right side channel and did the pre/main amp swap as you suggested and the output DID change to the other speaker so….I suppose the problem is in the main amp.
Any suggestions as to what to do or try next?
Thanks
I know this is an old thread but I’ll try my luck anyways….I have a HK 930 with a weak right side channel and did the pre/main amp swap as you suggested and the output DID change to the other speaker so….I suppose the problem is in the main amp.
Any suggestions as to what to do or try next?
Thanks
Wow what an old thread sorry i did not pick this up until now if the fault moved its in the preamp section
these old hk units suffer from faulty plastic transistor and caps are you still going to do it
trev
these old hk units suffer from faulty plastic transistor and caps are you still going to do it
trev
Yes the transistors need to be very high gain, a lousy design. Many phono preamplifiers suffered from this. I don't recall the current state of this unit but yes I still have it. It was given to me to repair but the owner never contacted me again. It's been several years and it's now just taking up space in my spare room. If you want it, let me know. As I recall, it was awaiting repair still, and perhaps now I have stock of transistors that would work. Nobody seems to use these old turkeys any more.
same trouble but fuse OK
Hi ! I up this thread because I have the same problem too. HK930
The fuse are okay.
The power section are okay.
The input switch are okay. (I try all input and the trouble stay the same)
what can I do now, I need help 😉
THK !
BenZ
Hi ! I up this thread because I have the same problem too. HK930
The fuse are okay.
The power section are okay.
The input switch are okay. (I try all input and the trouble stay the same)
what can I do now, I need help 😉
THK !
BenZ
Its more than likely either of the following
Coupling capacitors that have died out
Small signal transistors that have failed I can remember even twenty years ago having to replace the small signal transistors in the tone stage all of them failed in one way or another
Best of luck Trev
Coupling capacitors that have died out
Small signal transistors that have failed I can remember even twenty years ago having to replace the small signal transistors in the tone stage all of them failed in one way or another
Best of luck Trev
