No need as all commercial amps will have AC coupled inputs and the iPOD probably has AC coupled output as well.
Yes they're the ones I'm using. But I did plug them before I even powered up the amp. I know it's meant to be proper speaker leads but I only have the music intrument/microphone variants. But they're still the 1/4" TRS jacks
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Mic cable is probably under-rated for full power peaks, thats all. With long term usage at high volume, the cable might melt. I doubt that for such a short term test this is the problem, and it doesn't explain your amp failure.
Yes, that's what I was worried about, so I will look into high grade speaker cables if I can get an exchange.
you don't need high grade speaker cable.
Any 2core with 1sqmm or more will do.
The longer it is, then better to use more copper. It's rare to need more than 2.5sqmm (the old QED 79 strand)
Yes, 2core mains cable will do very well. It is available here in copper areas from 0.5sqmm upwards.
Any 2core with 1sqmm or more will do.
The longer it is, then better to use more copper. It's rare to need more than 2.5sqmm (the old QED 79 strand)
Yes, 2core mains cable will do very well. It is available here in copper areas from 0.5sqmm upwards.
Microphone cable might be highly capacitive, which could cause instability if you use yards and yards of the stuff, but's it very unlikely in practice. Mains lead as Andrew suggests is perfect.
If you are nervous of testing a new amp out, use a couple of back to back electroylitics to amke a large non polarised cap and connect in series with the speaker output, a couple of 2200uf's@63 volt is OK to play around with although it will limit extreme bass. Good enough to wind the amp up and see if it survives OK though.
If you are nervous of testing a new amp out, use a couple of back to back electroylitics to amke a large non polarised cap and connect in series with the speaker output, a couple of 2200uf's@63 volt is OK to play around with although it will limit extreme bass. Good enough to wind the amp up and see if it survives OK though.
The good news is that only one channel is fried. You can fix the blown channel by looking at the good channel. I've fixed 2500 Watt amps with no schematic by comparing the blown channel to the good channel. For starters, look for bad solder connections, signs of overheating, then ohmeter out everything in the output stage. Look for shorted outputs and open emitter resistors. Maybe a shorted driver transistor or two. Make sure the amp has been OFF for a day or two so the capacitors have had plenty of time to discharge!
Is that a Class H amp like QSC's RMX series, FET, or just a bipolar transistor amp. Couldn't find much about it here in the states.
I'd probably rather return it, having it being only 2 minutes old, there's no point voiding the warrenty by opening it, might as well get an exchange. I'm not entirely sure what class amp it is. If opening it didn't void the warrenty, I would open it and take a look at the circuit board. Thanks for the info though 🙂
Yea I'd return it and shop for a different brand. If you don't... I'd torture test it with a scope and a dummy load.
Input cables with plugging in different sources you have would be a start. It's possible to make a badly designed amp go unstable at the input.
Input cables with plugging in different sources you have would be a start. It's possible to make a badly designed amp go unstable at the input.
Hey everyone. I will be sending it back on Friday. I didn't actually take a pic of the amp in action, but I did take a video (hence bad quality) so I took a screenshot from that. Here's also what it did to my woofer. 🙁
Attachments
Hi,
include a print of that pic with the returned amplifier.
Email the pic when you make the claim.
The retailer should reimburse you for losses resulting from their faulty amplifier.
Do not accept a voucher. Do not accept a repair. Do insist on a full refund.
If you accept anything less you throw away many of your rights as purchaser.
The retailer will be aware of this and may try to persuade you to give up your rights.
He will even try to blame the manufacturer and/or importer. The contract is between the purchaser and the retailer. Do not let the retailer fob you off with diversionary tactics. Stay on the premises, preferably near the front door and/or sales desk. Stand your ground. Let other customers discretely overhear your complaint.
Do not shout. Do not lose your temper. Do not swear. Do not threaten anyone. Make sure you have no other appointments for later in the day. Wait until the Police ask you to leave.
The product was not of merchantable quality. End of. Refund!!!
Did you pay by credit card? They wield a lot of power on behalf of the purchaser's rights. Keep a copy of your written complaint to the retailer to send on to the credit card issuer. Let the retailer know that the credit card issuer is being sent a copy of the complaint/dispute.
Much of the protection offered by using a credit card is not available to a debit card user. But the sight of a copy being sent to the debit card issuer may be enough for the retailer to give in and refund your purchase cost. Don't be too hopeful that they will pay for the damaged speaker. The retailer probably has some small print that removes some of your rights. It starts getting tiresome and expensive to fight that cause.
include a print of that pic with the returned amplifier.
Email the pic when you make the claim.
The retailer should reimburse you for losses resulting from their faulty amplifier.
Do not accept a voucher. Do not accept a repair. Do insist on a full refund.
If you accept anything less you throw away many of your rights as purchaser.
The retailer will be aware of this and may try to persuade you to give up your rights.
He will even try to blame the manufacturer and/or importer. The contract is between the purchaser and the retailer. Do not let the retailer fob you off with diversionary tactics. Stay on the premises, preferably near the front door and/or sales desk. Stand your ground. Let other customers discretely overhear your complaint.
Do not shout. Do not lose your temper. Do not swear. Do not threaten anyone. Make sure you have no other appointments for later in the day. Wait until the Police ask you to leave.
The product was not of merchantable quality. End of. Refund!!!
Did you pay by credit card? They wield a lot of power on behalf of the purchaser's rights. Keep a copy of your written complaint to the retailer to send on to the credit card issuer. Let the retailer know that the credit card issuer is being sent a copy of the complaint/dispute.
Much of the protection offered by using a credit card is not available to a debit card user. But the sight of a copy being sent to the debit card issuer may be enough for the retailer to give in and refund your purchase cost. Don't be too hopeful that they will pay for the damaged speaker. The retailer probably has some small print that removes some of your rights. It starts getting tiresome and expensive to fight that cause.
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Hi,
T&Cs mate. They won't be held responsible to damage to property, I just want a replacement to be shipped at their cost. I'm gonna be arranging a pick up for the faulty part Friday. The speaker was only some cheappo 12inch 200W Skytronic full range anyway, only 15 quid dent. Anyway I got that from a seperate supplier, and I told them it blew because it was faulty, and no hassle, I got a replacement sent today without even needing to send the damaged one back. I've fitted it, ran the speakers on the Sansui amp and they sound great again! But I'm still disappointed because of the amp, as it will miss my birthday which will be tomorrow so the idea of a disco is out of the window. 🙁
Mooly,
I'm just glad the crossover (pictured in background) didn't blow as that was a costly Emience piece of kit 😱
But yeah, got a new woofer free and speakers sound great. Might post a pic of them in multi way speaker DIY projects
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Blocking cap
"Could I have caused this by connecting the speakers with musical instrument/microphone cable rather than using professional speaker cable?" Personally, I use 4SO-10 power cable to hook up speakers. Jacketed 3 wires US 10 gauge insulated to 600 V. Professional use is hooking up 3 phase motors at 480 VAC, or extension cords in underground coal mines. Found in the dumpster at all factories with three phase. I realize I'm the only person in the world that worries about DC in the speaker, but you should have bought a (reviled, dispised, badly reviewed in all the magazines) Dynakit ST120 that has a 3300 uf capacitor in each speaker lead. My speakers are worth 20X what the $50 blown up amp cost me. I fixed it without help, but it has the actual rated power and sounds better due to help available on this forum. A new 15" Black Widow woofer for my speakers is about $200. Other possible safe alternatives are $50 Hammond organ PR10 tone cabinet that has about the last transformer coupled transistor output amp made that I know of. They are not much on high frequencies, though. Dynakit ST70 clone transformer coupled output tube amp kits are in current production at triodeelectronics. Or you can buy various $1000 up professional grade amps with protection circuits built in to cover the inherently dangerous design of output transistors direct coupled to the speaker.
"Could I have caused this by connecting the speakers with musical instrument/microphone cable rather than using professional speaker cable?" Personally, I use 4SO-10 power cable to hook up speakers. Jacketed 3 wires US 10 gauge insulated to 600 V. Professional use is hooking up 3 phase motors at 480 VAC, or extension cords in underground coal mines. Found in the dumpster at all factories with three phase. I realize I'm the only person in the world that worries about DC in the speaker, but you should have bought a (reviled, dispised, badly reviewed in all the magazines) Dynakit ST120 that has a 3300 uf capacitor in each speaker lead. My speakers are worth 20X what the $50 blown up amp cost me. I fixed it without help, but it has the actual rated power and sounds better due to help available on this forum. A new 15" Black Widow woofer for my speakers is about $200. Other possible safe alternatives are $50 Hammond organ PR10 tone cabinet that has about the last transformer coupled transistor output amp made that I know of. They are not much on high frequencies, though. Dynakit ST70 clone transformer coupled output tube amp kits are in current production at triodeelectronics. Or you can buy various $1000 up professional grade amps with protection circuits built in to cover the inherently dangerous design of output transistors direct coupled to the speaker.
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Yeah, I like the idea of caps in the outputs. You could build a little box with 2 caps in it and it would always protect your speakers.
I bet its just a loose connection. If you can open it up without breaking any seals, it might be worth looking at. If its just a loose connection, it would be easier to fix, than shipping it back.
Too bad for your speaker, though.
I hope they take it back, but some companies can be dirt bags to deal with. Good luck.
I bet its just a loose connection. If you can open it up without breaking any seals, it might be worth looking at. If its just a loose connection, it would be easier to fix, than shipping it back.
Too bad for your speaker, though.
I hope they take it back, but some companies can be dirt bags to deal with. Good luck.
Yeah, thanks for the input. Over the holidays when my GCSE's are over, I might make some DC protection modules, but only once the exam pressure is gone. Replaced the driver, speakers work but I don't think it's worth opening up and voiding the warrenty because it could be more than a loose connection. It's going to be sent off tomorrow.
Lack of protection
Not all amp designs are stable into capacitative loads, so ask the question before you buy to hook up into series capacitors. I don't know which ones. There are speaker protection threads on this forum, but they mostly run to fuses (good but don't detect low level DC), timers to hold things off until the turn on transient is over, and diac-traic voltage clampers across the output, which could prevent 220VAC getting into the speaker but on a CS800 with +-100VDC rails and a 120 VAC power input, the point is ?????. (My CS800 has triacs, I'm afraid to use it). Somebody posted a Crown brand protection circuit which has a microprocessor monitoring several blanked out box fault sensors- the only way I know to duplicate that is buy an in warrenty Crown amp.
Not all amp designs are stable into capacitative loads, so ask the question before you buy to hook up into series capacitors. I don't know which ones. There are speaker protection threads on this forum, but they mostly run to fuses (good but don't detect low level DC), timers to hold things off until the turn on transient is over, and diac-traic voltage clampers across the output, which could prevent 220VAC getting into the speaker but on a CS800 with +-100VDC rails and a 120 VAC power input, the point is ?????. (My CS800 has triacs, I'm afraid to use it). Somebody posted a Crown brand protection circuit which has a microprocessor monitoring several blanked out box fault sensors- the only way I know to duplicate that is buy an in warrenty Crown amp.
🙂 It's capacitive loads connected directly across the output (in parallel) that cause problems, usually in the 0.1 to 1uf range that really upset amplifiers... series connection to the load via a large value cap has zero effect on the stablility.
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