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cooky560
07-30-2010, 06:05 AM
Hello, I'm new here so if this isn't the right place to post this, I apologise in advance.

I own a Technics SA-160L which serves as secondary amplifier for when I listen to music at my desk, like as I post this for example, however very recently (over the past 2 or 3 weeks) it appears to have lost a large portion of it's sound, the bass is considerably duller and the only cure for this is to sit literally on top of the speakers, or raise the volume to that which is too loud for others in the building, is the amplifier nearing the end of its life? If not how can I remedy this problem?

pixelthis
07-30-2010, 08:03 AM
PROBABLY blew a cap.
Isnt a solid state device or you wouldn't hear anything, so its secondary, and thats usually
a cap(capacitor).
If its a Technics its probably old, I wouldnt bother fixing it, as there are a lot of powered speakers out there that are a lot cheaper, theres' also a company that specializes in
small digital amps. SORRY, but I lost their link.:1:

Geoffcin
07-30-2010, 08:23 AM
Hello, I'm new here so if this isn't the right place to post this, I apologise in advance.

I own a Technics SA-160L which serves as secondary amplifier for when I listen to music at my desk, like as I post this for example, however very recently (over the past 2 or 3 weeks) it appears to have lost a large portion of it's sound, the bass is considerably duller and the only cure for this is to sit literally on top of the speakers, or raise the volume to that which is too loud for others in the building, is the amplifier nearing the end of its life? If not how can I remedy this problem?

The cause could be as simple as a dirty connector. Try removing the RCA jacks from both the amp and the source, and reinstalling them, giving them a few twists while doing it. If it sounds better then it was some corrosion in the contacts. A lot of times what sounds like a big problem often isn't.

Good luck!

cooky560
07-30-2010, 09:48 AM
Thanks for both your suggestions, I tried reconnecting the RCA jacks, and improving the connection to the speakers, this increased the volume but the sound is still the same. How do I tell if a cap is broken?

Geoffcin
07-30-2010, 10:20 AM
Thanks for both your suggestions, I tried reconnecting the RCA jacks, and improving the connection to the speakers, this increased the volume but the sound is still the same. How do I tell if a cap is broken?

It's unusual that you would have both problems at the same time. My guess is that there's a problem with your RCA connector and/or speaker cabling. I would switch them both out before looking for deeper problems.

Also, if your using your computer to play music there are many setting than can affect playback. You may have engaged a eq setting that is making the music sound wrong.
I would hook the amp directly to a CD player to proove it's not the computer causing the problem.

cooky560
07-30-2010, 10:43 AM
I tried a CD player and it still feels like something is missing, I'm not sure how helpful that is

Geoffcin
07-30-2010, 11:02 AM
I tried a CD player and it still feels like something is missing, I'm not sure how helpful that is

It's very helpful as it eliminates the computer as the source of the problem.

After you change out the RCA and speaker cables, if that does not fix your problem you should try the speakers with a different amp. The idea is to narrow down the possibilities until your left with no other.

cooky560
07-30-2010, 01:49 PM
Just incase it helps I've taken some image of the storage and guts of the unit:

One (http://dropped.richardcook.info/inside1.JPG)
Two (http://dropped.richardcook.info/inside2.JPG)
Three (http://dropped.richardcook.info/inside3.JPG)
Store (http://dropped.richardcook.info/home.JPG)

Nasir
07-30-2010, 02:02 PM
The way I see it, the problem can be in one of 5 places:
The source, the amp itself, the speakers, the wires from the source ( those with the 2 RCA Red and White or Black plugs connectors, these connect your CD Player to the amp ) or the 4 speaker wires that come out from the amp and go into the Left and Right speakers (usually Red and Black for each speaker)
Considering the fact that BOTH speakers sound dull, I would change the amp first leaving all other factors constant. If it is the amp ( OR in case you donīt have a second amp ), then the next thing to do is connect the incoming RCAs to another source input, ie, instead of plugging into the CD input connector, use the AUX or Video inputs ( NOT the Phono inputs!!!!) I noticed that you tried a CD player, but did you use a different input as mentioned now?
Next, try using another set of speakers. If you donīt have a spare set of speakers, I would try new RCA cables followed by normal wire to replace speaker cables. GOOD LUCK !!
If you think the above is confusing, let me know, I will explain better.....

cooky560
07-30-2010, 02:11 PM
I've tried reconnecting the wires (or another amp for that matter), don't have access to other wires unless I start gutting my main system, I may be able to borrow some from somewhere. I have tried moving the CD input to the monitor input, this sounded worse lol.

basite
07-31-2010, 02:32 AM
probably something dirty in there, you could get some electronics contact cleaner, and give all the pots, switches and connections a good spray (the actual switch of course, not the lever on the outside, and the potentiometers for the volume, balance, bass,...

I see no "damage" as in blown caps or leaking caps, or anything, really, so I guess it's dirt...

Nasir
07-31-2010, 12:41 PM
I would tend to agree with Basite on the fact that there is no visible damage of electronic components from the photos. Since both speakers sound bad, it has to be something in common to both channels. Its rare to have both pairs of wires suffering from the same problem.... and both speakers as well. If I were to hazard a guess, it would be the amp power supply that is running low....

cooky560
07-31-2010, 12:44 PM
would it be easier (and better) for me to replace the amp with an amp suitable for the same purpose

basite
07-31-2010, 01:30 PM
would it be easier (and better) for me to replace the amp with an amp suitable for the same purpose


it's worth a try to clean it, if you have some free time, a bottle of contact cleaner spray will set you back, like, $10, at the very most (unless you buy deoxit, which is well, better, but not necessary for you IMHO), a new amp will cost you at least 10 times that when you go used.

and a bottle of contact cleaner will always be useful at some other time...


just, remove the top cover, and if possible, the front panel of the amplifier, and spray on as much as necessary, while turning the knobs and switching the levers and things...

if that doesn't help, then go on to a new amp...

but your problem really sounds like dirt somewhere in the pots and switches...

does your amp have a "tape" switch? press/switch them all a few times, see if it does something, those things are evil when it comes to dirt...

there is always better, but if you were happy with your amp before it started acting up weird, why buy a new one if you can easily try fixing it?

one small word of advice, the amplifiers, or any audio component, for that matter, was designed to be standing on it's feet. there are no moving parts inside there, but heat dissipation (heatsinks, other components that get hot), were put in a way that when they got hot, the heat dissipated optimal when it was standing on it's feet, not sideways. Same for dirt...

but then again, it isn't such a big amp, and I doubt that you are using it so it would actually get really hot, but having some space to "breath" is never a bad thing :)

Keep them spinning,
Bert.

cooky560
07-31-2010, 03:04 PM
.

does your amp have a "tape" switch? press/switch them all a few times, see if it does something, those things are evil when it comes to dirt...

It has 2 "monitor" switches if that's what you mean but none of them are labelled tape


.
there is always better, but if you were happy with your amp before it started acting up weird, why buy a new one if you can easily try fixing it?

I was happy with it yes, it was great for listening at my desk