Impedance of AMP vs SPEAKERS

[attilavilagi]

Hi

I bought a "1983" Realistic SA 500 amp recently. Unfortunately I connected 6 ohm impedance speakers to try it out thinking the 2 ohms difference would not make a harm to my amp....The amp started to smoke where the power switch is, I managed to unplug it within seconds but still don't know whether it survived. I took off the cover to check it and what I can see so far is an capacitor next to the switch is damaged(the outer cover).
Is it OK to try it with another pair of speakers? this time with 8 ohm impedance (Acoustic Solutions AV-21).

 

[koushik]

I don't think this happened due to the 6 ohm load. There is nothing like impedance matching in Amp-speaker combo.

Yes, higher load can tax an Amp on prolong use on very high volume but nothing instantaneous is expected.

DO NOT pair it with any other speaker as of now. Get the amp checked by a technician. Also check the speaker if it got shorted anywhere.

 

[anuragn]

Hi

I bought a "1983" Realistic SA 500 amp recently. Unfortunately I connected 6 ohm impedance speakers to try it out thinking the 2 ohms difference would not make a harm to my amp....The amp started to smoke where the power switch is, I managed to unplug it within seconds but still don't know whether it survived. I took off the cover to check it and what I can see so far is an capacitor next to the switch is damaged(the outer cover).
Is it OK to try it with another pair of speakers? this time with 8 ohm impedance (Acoustic Solutions AV-21).

Check what is the power supply voltage required by your amp. Hope it is not a 110V version which got burnt due to 220V.

 

[attilavilagi]

Hi

thanks for the reply. I'm just wondering why it didn't blow the fuse. it was a thick white smoke coming out, would it happen if any of the two speakers were connected wrong( like mixing the +/- wire or so? I bought this amp from ebay and apparently it was tested.

 

[Santy]

6 ohm load on 8 ohm amp will not cause immediate harm to the amp. Infact as Koushik said, even in the long run there wouldn't be much damage the speakers can do to the amp, unless it is overdriven at high volumes for prolonged duration without adequate heat dissipation around the amp.

Have you played your amp with any other speaker before this incident? Please post some pics if possible. It looks like a PSU failure.

 

[attilavilagi]

To: anuragn

thanks for your reply. The voltage is 220v definitely. so must be another issue.

 

[attilavilagi]

To: Santy

Thanks for reply. I will take some pics and send it to You.

 

[greenhorn]

What about the old electrolytic power supply caps committing hara kiri? Quite possible in an amp of this vintage.

 

[attilavilagi]

To: greenhorn

Hi

actually I have a picture about the smoking part, but I don't know how to upload good/res pictures to this forum. I registered today. is there any way to do so?

 

[attilavilagi]

thanks people for replies so far, I've arrange already an electrician to have a look on it and I will let You know what's the trouble. Cheers!

 

[ketansethi1987]

Try getting it replaced

Seems like you just bought it.

post a link of ebay page you bought it from

 

[attilavilagi]

Hi ketansethi1987

I have just written to them I will see what they can do. They are a 100% sellers so I hope the best.