Sharp Optonica GS-4520A Speaker Connections.

I recently bought this amp off eBay cheap. The right channel doesn't work in the headphones (which I plan to get repaired), however the speaker connection are something else



Has anyone seen this style before? A speaker only has a positive and negative - why the need for 6 points?

Did a quick search on the net - you are not the only one to have this issue, judging by the photos in the attached link I would just swap them for a more conventional outlet plug.

http://www.audiokarma.org/forums/archive/index.php/t-268190.html

Update:

The issue with the right channel (I suspect) is a blown fuse (I wont know until I get some).

I recently purchased a service manual on the amp.

Maxium Power Output: 36W
Constant power output: 5W per channel

Curcit: Built in 4 channel discrete, 4 channel matrix stereo system with FM multiplex.


The wiring diamgram of the speaker plugs says that only three of the prongs are active and one of those is bridged to the another prong on another input.

eg:



Is this bridged for mono or is it to do with a quad setting?

The snippet of the wiring diagram you show is of the 4 channel balancing controls that are on the left front of the receiver just under the output display.

VR in the part number signifies Variable Resistor.

These are not the output connectors for the speakers.

Cannot tell from this if it is bridged for mono.

Sorry, my mistake.



https://www.quadraphonicquad.com/forums/attachment.php?attachmentid=9027&d=1358461956

I hope this helps. The speaker section below on the diagram above seems to make more sense when flipped upside.




Inside



Outside

From what I can see looking inside the unit and looking at the diagram. All the channels share a (-) BUT there are TWO positives on the FRONT CHANNELS. From what the diagram is telling me, Pin (3) on each front speaker goes to a tweeters (+) and Pin (4) goes to the woofer (+), while Pin (1) goes to both (-).

Wouldn't this normally be dealt with in the crossover? Is this normal for a Quad set-up?

UPDATE:

I placed the wire on the Pin (4) then Pin (3) with the (-) in. Just as I thought - one pin is treblely and the other is bassey.

Surprising, looks like the front speakers are bi-amped!

http://en.wikipedia.org/wiki/Bi-amping

Bonzodog said:

Surprising, looks like the front speakers are bi-amped!

http://en.wikipedia.org/wiki/Bi-amping

Click to expand...

Since I don't want to pull apart my speakers. Could I just have a short wire bridging the two postives - will that cause any issues?

If the unit is truly bi-amped, then feeding the output of the two amplifiers into each other by shorting their outputs together may cause damage to your unit.

If the unit is set up to be bi-wired,

http://en.wikipedia.org/wiki/Bi-wiring

then you may safely short the high and low output of each individual channel together.

Check the output section on your schematic diagram to see which is true, or you may damage your unit.

So judging by the diagrams - If I was going to rewire my speakers - would this be correct?:

Front Speakers: Pin 4 to Tweeter (+), Pin 3 to Woofer (+), Pin 1 to Tweeter and Woofer (-)
Rear Speakers: Pin 2 to Crossover (+), Pin 1 to Crossover (-)

2nd question: The amp is rated at Maxium Power Output: 36W @ 8ohms, Constant power output: 5W per channel @ 8 ohms. If I wanted to build some speakers then what should my Tweeters and Woofers be rated at?

Bump

I have the same issue with a SHARP GS-9200 I picked up at the local "waste transfer station" (except less confusingly the rear speaker connections seemed to take just two-pronged plugs). Unfortunately, the unit did not come with the original Golden Sound speakers/ cables/ plogs so I could not count wires/ verify that there was no crossover inside the front speakers etc. I am also curious to hear what the suggestions are re ratings for the woofers and tweeters in 2-way front speakers, or whether both front/ rear are both rated 8 ohms (or perhaps only 4 ohms?).