No.. I'm NOT going to sing my entire post.. maybe another one when I have time to waste.. yeah.. anyway.. one of my speakers cuts out... 🙁 (why am I posting this? I should just solve the problem for myself) anyway.. my right.. or left... anyway.. one speaker cuts out when you crank it.. 🙄 heh anyway.. its abit annoying... the amp is slightly clipping, I know that, but it seems like one channel may be clipping more than the other... if ya crank it even higher you can very much hear the clipping in both channels and the lights on the amp dim, and then both speakers go off... so.. do the speakers have an "overload" protection, or does the amp have a clipping protector for each channel, and one channel clips before the other? 🙁 the amp is a Realistic STA-225 AM-FM Stereo Reciever, its about 30 years old or so, and has never needed any repairs (I'm quite inpressed) the speakers are some crusty Acculab speakers consisting of two 10inch woofers, 1 midrange, and 2 tweeters, all cone drivers... they are rated at 90watts rms... pretty crushy.... the magnets on the woofers are about 7cm in diameter... I KID YOU NOT!! they totally suck.. but do get fairly loud, but not all that low... sealed enclosures, what would you expect? anyway.. its all I could afford.. (cost me nothing) so I am not complianing TOO much... my parents however are, cos these things get loud enough to rattle my window, and loud enough for all our neighbours to hear them with my doors shut.. 😀 BUT! alas... one cuts out... 🙁 I have considered just making a bigger amp.. I was going too anyway... so... hmm.. lol
What are the output devices in your receiver? Are they STK-XXX Chips? Perhaps its a thermal thing.
NEVER stop singing. (unless we can hear you)
NEVER stop singing. (unless we can hear you)
umm... from memory it uses transistors... I'd have to check though... not now though... I'm using it... lol
I'll check that out though.... I know my other amp had an overheat protection and that used transistors and when either of the heatsinks reached a certain temp it would cut off both speakers using a relay.... quite a good idea actually, except when you are trying to run 4 ohm speakers off it on a 35 degree hot day... 🙄
I don't think it is heat with this amp... cos even if you turn it on and crank it straight away before it gets time to heat up much it still switches off.. 🙄
I'll check that out though.... I know my other amp had an overheat protection and that used transistors and when either of the heatsinks reached a certain temp it would cut off both speakers using a relay.... quite a good idea actually, except when you are trying to run 4 ohm speakers off it on a 35 degree hot day... 🙄
I don't think it is heat with this amp... cos even if you turn it on and crank it straight away before it gets time to heat up much it still switches off.. 🙄
My guess...
.. is that the speaker go pretty low resistance, and the amp has shorting protection.
.. is that the speaker go pretty low resistance, and the amp has shorting protection.
Does the sound come back really quickly when you turn the sound down, or does it take 2 seconds or more then come back?
Based on the age of the amp, I'd be surprised if it has it's own inbuilt speaker protection, you might find however the speakers have some polyswitches in them.
If It's polyswitches the speakers will go off whilst the current is too high (due to the clipping), and once you reduce the current (in your case by turning down below clipping) they should reset after a few seconds and everything should return to normal.
This is what a polyswitch (in my experience) looks like, in case you are feeling adventurous
and want to peek inside your speakers.
Regards,
Tony.
Based on the age of the amp, I'd be surprised if it has it's own inbuilt speaker protection, you might find however the speakers have some polyswitches in them.
If It's polyswitches the speakers will go off whilst the current is too high (due to the clipping), and once you reduce the current (in your case by turning down below clipping) they should reset after a few seconds and everything should return to normal.
This is what a polyswitch (in my experience) looks like, in case you are feeling adventurous
and want to peek inside your speakers.Regards,
Tony.
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when the speaker goes off after 2 or 3 seconds it comes back on again without any adjustment of the volume control... Polyswitches increase the resistace so the speaker is still on, but quieter... I BELIEVE this is whats happening, but it gets so quiet I can't see that it is just a polyswitch increasing the resistance.... when the sound goes off and comes back on after a few seconds, it then goes off again after a few seconds, and so on... 🙄
Maybe not. When my polyswitches cut in there is NO sound at all until they reset (although it's a long time since I have witnessed that and I may have had a few drinks at the time so this account may not be so reliable 🙂
It sounds like some sort of protection mechanism, but whether it's in the speakers or the amp is hard to say. I guess you could borrow an amp from someone else and crank it to see what happens 🙂 Of course if the protection is in the amp, then maybe you will fry your speakers........
The other option would be to not play it so loud. If you can hear it clipping then it mustn't sound too good at that volume anyway???
Regards,
Tony.
It sounds like some sort of protection mechanism, but whether it's in the speakers or the amp is hard to say. I guess you could borrow an amp from someone else and crank it to see what happens 🙂 Of course if the protection is in the amp, then maybe you will fry your speakers........
The other option would be to not play it so loud. If you can hear it clipping then it mustn't sound too good at that volume anyway???
Regards,
Tony.
it doesn't sound too bad... only slightly clipping.. the speakers are so bad anyway you can hardly hear it.. :S one speakers does seem to sound worse than the other... I will try switching speaker channels.. 🙂
it has to be loud so all the neighbours can hear it.. DUH!!
it has to be loud so all the neighbours can hear it.. DUH!!
I think it has gotten worse... lol like it cuts out at a lower volume now... perhaps I am just going deaf... I really should get one of those cheap SPL meters.. lol
just try something for me...
grab half a dozen say 8-10 ohm (or about) 10w resistors
parallel 3 each side so you will have about 3 ohms at 30w and put it in series with the speakers.
grab half a dozen say 8-10 ohm (or about) 10w resistors
parallel 3 each side so you will have about 3 ohms at 30w and put it in series with the speakers.
Re: just try something for me...
10 watt resistors are too expensive.. it cheaper to buy two 5 watt.. lol I don't have any resistors.... are you thinking the resistance of the speakers is too low? the boxes have a nominal impedence of 8ohms and a (measured) DC resistance of....
4.2 ohms on the one that switches off all the time...
and
3.5 ohms on the "good" one
which doesn't explain why the one that switches off does... 🙄 thats wrong... lol how can they be so different? 🙄
Andy Graddon said:
10 watt resistors are too expensive.. it cheaper to buy two 5 watt.. lol I don't have any resistors.... are you thinking the resistance of the speakers is too low? the boxes have a nominal impedence of 8ohms and a (measured) DC resistance of....
4.2 ohms on the one that switches off all the time...
and
3.5 ohms on the "good" one
which doesn't explain why the one that switches off does... 🙄 thats wrong... lol how can they be so different? 🙄
SkinnyBoy said:
Almost certainly, it's your amp. It's pretty unlikely both speakers would go off at once otherwise. Quite possibly (as the lights are dimming) it's in the power supply - maybe it has a thermal trip or overcurrent protection.
Does it have a balance control? If you make one speaker much louder than the other, do they still both go off at once? If so, it would confirm it's the amp.
To rule out your speakers, you could use a judiciously-chosen light bulb as a load (12V 50W car headlight bulb is roughly right).
Cheers
IH
they only both go off when both channels hit clipping point... ok.. I tried a different amp and the same channel still goes off... they have polyswitches in them and for some reason one triggers more easily than the other... while I had the boxes apart, I drew up the crossover circuit.. 😉
Now... we much note that the speakers have printed on the front:
Crossover Frequencies: 48Hz... 1,500Hz... 7,500Hz... 10,000Hz
and now for the circuit... heh... I was feeling ARTY!! 😀
Now... we much note that the speakers have printed on the front:
Crossover Frequencies: 48Hz... 1,500Hz... 7,500Hz... 10,000Hz
and now for the circuit... heh... I was feeling ARTY!! 😀
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I wanna do something about the crossovers.... what speakers should be connected in phase with what? 🙂
The other thing you could do is use a separate polyswitch on each speaker (although with the number of drivers you have shown that could be a tad expensive), after the crossover components, then you use a small one for your tweeters and bigger ones for the bass drivers, should get better power handling, you'll probably find that with one only, it's been chosen pretty conservatively.
The other weird thing is that there doesn't seem to be anywhere near enough component's to give you that many crossover points, I guess the other thing is that they are pretty much (from my limited knowledge of xovers) only 1st order xovers. Looks completely cheap and nasty to me (sorry)...... Is it worth spending bucks on making better ones?????? Certainly it should be possible to make the speakers sound better than with xovers like the ones you depicted!
Regards,
Tony.
The other weird thing is that there doesn't seem to be anywhere near enough component's to give you that many crossover points, I guess the other thing is that they are pretty much (from my limited knowledge of xovers) only 1st order xovers. Looks completely cheap and nasty to me (sorry)...... Is it worth spending bucks on making better ones?????? Certainly it should be possible to make the speakers sound better than with xovers like the ones you depicted!
Regards,
Tony.
EXACTLY!!! how does one obtain 4 crossover points with only 3 components.... 
anyone? someone? hello hello..... 🙂 heh forget it... I am making some towers that were going to house one peerless 8inch woofer each... BUT!!! considering that with a suitable tuning frequency to get a flat response in a large, 60litre enclosure, the power handeling at 40Hz is only 15watts before they reach X-max... 🙄 so.. instead I am putting two 8inch venom subs per box.. 🙂 which makes it MUCH louder and lower.. 🙂 and a much more realistic power handeling... and... not much more expensive than the peerlesses.. 🙂
anyone? someone? hello hello..... 🙂 heh forget it... I am making some towers that were going to house one peerless 8inch woofer each... BUT!!! considering that with a suitable tuning frequency to get a flat response in a large, 60litre enclosure, the power handeling at 40Hz is only 15watts before they reach X-max... 🙄 so.. instead I am putting two 8inch venom subs per box.. 🙂 which makes it MUCH louder and lower.. 🙂 and a much more realistic power handeling... and... not much more expensive than the peerlesses.. 🙂- Status
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