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JVC A-GX series (output power of A-GX3 if someone knows)

There's not a single A-GX listed in the library, there's been four. A-GX1, A-GX2, A-GX3 and A-GX5.

Also, if someone knows the power output of A-GX3



Pioneer SX-680 distortion right side

Hi, I'm new to this site and am hoping that someone can offer some advice to a problem I'm having. I purchased a Pioneer SX-680 a couple of years ago from a local thrift store and have finally got the time to set it up and use as my shop-tunes receiver. 1st thing I did was take the cover off & blow out the dust, did a quick visual inspection, threw the cover back on & hooked up an old pair of Bose 201s, tuned in to the local FM station and was actually pretty impressed at the sound quality, for a while I mean. after about an hour of normal & higher volume listening, I cranked it up a bit and heard what sounded like a click, followed by pretty nasty (continued) distortion on the right side only. And thats where I'm at. The distortion is on the right side of both A&B speaker settings. I switched speakers around to make sure it wasnt a speaker problem, pulled the cover checked fuses, their all good, thats as far as I've got, mainly because I dont have a clue as to what I should be looking for! Any help would be greatly appreciated.

karodimitrov's picture

Re: Pioneer SX-680 distortion right side

First check whether the problem occurs only tuner position.If not-check the power supply of the main amp.Are there differences in the voltages of both channels and if there are-check items around.Think the problem is STK,but may be electrolytic cap.You should again to open the cover,to looked around and measure.

Re: Pioneer SX-680 distortion right side

Ok, I hooked up a turntable & same problem. One thing I need to make clear is, although I'm a pretty fair mechanic, welder, etc, schematics & circuitry, electronics in general is definitely not my field. I've soldered switches and did quite a bit of wiring and use the volt ohms meter regularly here on the farm, but this sort of thing is new to me. Because I live in a very small town & there is no place in town that works on these things, I'd kind of like to see if I can fix it before I throw it in the scrap pile. Kind of hoping maybe someone could kind of walk me thru it or at least bear w/ me for a couple of steps, so I can kind of get an idea if this is something I can handle or a bit over my head. Thanks in advance.

karodimitrov's picture

Re: Pioneer SX-680 distortion right side

First you download service manual from here:
https://www.hifiengine.com/manual_library/pioneer/sx-680.shtml
Then look for any obvious damage blown capacitor, transistor, or integral.Look carefully both STK of main amp.If there is nothing visible - will have to be measured.When you look at the scheme - bottom left you have two identical amplifiers ending with STK.Ibid have given voltages in certain control points.You must turn on the receiver and to measure these voltages.You have two identical channels and in the same points of one and the other channel have the same voltages.It is permissible to have slight variations of voltage between the same points (2-3%) but if there is striking difference - then you discovered the problem.
The remaining work is in your hands.

Re: Pioneer SX-680 distortion right side

I will check it out in the morning, your help is greatly appreciated...

karodimitrov's picture

Re: Pioneer SX-680 distortion right side

P.S.
Go through well for swollen capacitors.

Re: JVC A-GX series (output power of A-GX3 if someone knows)

With some help from google:
JVC A-GX1 : 8 Ohm: 2x 25 Watt (0,02%)
JVC A-GX2 : 8 Ohm: 2x 45-50? W
JVC A-GX3 : 8 Ohm: 2x 50-60? W
JVC A-GX5 : 8 Ohm: 2x ? W

Re: JVC A-GX series (output power of A-GX3 if someone knows)

hi, finally found it on some obscure page. A-GX3 seems to be 80W! Not really great THD, but it would explain why I like the bass more on it than on my JA-S22.

I paid roughly the same amount for it (50€) and I'm quite happy with it.

Re: JVC A-GX series (output power of A-GX3 if someone knows)

Thanks!

I figured it would be something like that for A-GX3 (considering year of make and power consumption).

I have both A-GX1 and A-GX3, and A-GX3 is taller, deeper, and has two humongous transformers (akin to the ones in my JA-S22), while A-GX1 is short, shallow and has no transformers and no weight.