Hi all
I'd like to let you share what happened to me with this company.
I have bought and received some EX3 drives. Fine.
recently, I tried to push them with a good solid state amp and both blew.
It was the second time it happened.
the first time I sent the blown one in a double packaging, fully insured.
they answered that the parcel had been crushed by the post office and that I had to pay for the repair. I never got evidence of what happened and could not claim anything from the post office.
this time one of the drives which I sent arrived OK. they looked at it and said the following: (please better sit !):
Hi Billy
The EX3 drive unit has now been inspected.
The coil wire is not only blistered, but the speech coil is buckled. This suggests more ampage than voltage is going through the coil.
The problem lies with the amplifier, as you would be unable to listen to the volume needed to cause such damage, it would be unbearable.
Therefore, the amplifier either needs rectifying or you may wish to consider changing the amplifier altogether, otherwise this problem will continue to occur. As previously mentioned, Lowther drive units require only 1-3 watts to fill a normal listening environment. There are various low watt amplifiers on the market which would enhance the sheer musicality of Lowther drive units.
We can fit a new diaphragm to this unit for you, at a cost of GBP90 plus carriage (quote exclusive of VAT as you have a registered VAT number).
If you would like to return the second unit of the pair for repair, this will save on return carriage costs for you.
great technical analysis indeed, the amp gives out too much ampage and not enough voltage !!!
repaired mine alone with no trouble and found an incredible thing: while Lowther advertises and sells a choice between aluminium or silver coils, I found an ordinary PAPER coil inside !
So this is total fraud and either they deliver the propser thing or there will be blood on the sidewalk.
Please read carefully !!!
I'd like to let you share what happened to me with this company.
I have bought and received some EX3 drives. Fine.
recently, I tried to push them with a good solid state amp and both blew.
It was the second time it happened.
the first time I sent the blown one in a double packaging, fully insured.
they answered that the parcel had been crushed by the post office and that I had to pay for the repair. I never got evidence of what happened and could not claim anything from the post office.
this time one of the drives which I sent arrived OK. they looked at it and said the following: (please better sit !):
Hi Billy
The EX3 drive unit has now been inspected.
The coil wire is not only blistered, but the speech coil is buckled. This suggests more ampage than voltage is going through the coil.
The problem lies with the amplifier, as you would be unable to listen to the volume needed to cause such damage, it would be unbearable.
Therefore, the amplifier either needs rectifying or you may wish to consider changing the amplifier altogether, otherwise this problem will continue to occur. As previously mentioned, Lowther drive units require only 1-3 watts to fill a normal listening environment. There are various low watt amplifiers on the market which would enhance the sheer musicality of Lowther drive units.
We can fit a new diaphragm to this unit for you, at a cost of GBP90 plus carriage (quote exclusive of VAT as you have a registered VAT number).
If you would like to return the second unit of the pair for repair, this will save on return carriage costs for you.
great technical analysis indeed, the amp gives out too much ampage and not enough voltage !!!
repaired mine alone with no trouble and found an incredible thing: while Lowther advertises and sells a choice between aluminium or silver coils, I found an ordinary PAPER coil inside !
So this is total fraud and either they deliver the propser thing or there will be blood on the sidewalk.
Please read carefully !!!
I think the metal they refer to is the wire, not the former. Aluminum has lower conductivity than silver, but lower mass. Take your choice.
What sort of amp have you been using?
No, it is not the wire which is in aluminium: the wire in thin plain usual copper. More, its insulation appeared pretty weak: disappearing with the heat of a small soldering iron.
they say it is rated to 100 watts power handling, believe me with such a gauged copper wire it is a max of about 30 watts you can expect.
they say it is rated to 100 watts power handling, believe me with such a gauged copper wire it is a max of about 30 watts you can expect.
... my amp was at the first time a A class 6080 triodes (paralleled, own design, was published by Mr Hiraga some years ago) and now it is a KA9X sstate Kenwood. the triode amp was to harsh with those drives, well known for being very hard to the ear.
Your service experience would certainly be frustrating, but publicly claiming fraud and threatening bloodshed is not required or prudent.
If you're happier with the sound of your Kenwood amp, it might well be time to consider another brand/type of driver.
Frankly, I think the Lowther repair agent's suggestion that both drivers should be reconditioned is very wise, which you can either choose to follow and then resell the drivers to avoid future damage, or continue to repeat the same actions with the expectation of different results.
If you're happier with the sound of your Kenwood amp, it might well be time to consider another brand/type of driver.
Frankly, I think the Lowther repair agent's suggestion that both drivers should be reconditioned is very wise, which you can either choose to follow and then resell the drivers to avoid future damage, or continue to repeat the same actions with the expectation of different results.
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🙂
An understatement I might have expected from an Englishman.
I have run Lowther drivers for years off of a 100w/ch Yamaha HT receiver, although they do sound better on my 9w/ch PP tubes. Your drivers should have been complaining long before you fried them. Don't know.
Bob
I run mine EX 3's with 180W Hypex amps, no problems. Have you per chance tried checking for DC offset on the output of your amps? Lowthers hate DC🙂
Regards,
Peter
Regards,
Peter
A quick Google search on that Kenwood unit:
KA9X
Kenwood KA-9X info anyone? [Archive] - AudioKarma.org Home Audio Stereo Discussion Forums
...................................................
Kenwood KA-9X | Owners Manual, Service Manual, Schematics, Free Download | HiFi Engine
............................................
KENWOOD KA-9X 9XG SM Service Manual free download, schematics, eeprom, repair info for electronics
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Ideas:
1. The amperage/voltage spikes provided for musical peaks from the staged amps are too much for the drivers. Perhaps the power jumps in too fast or something like a turbo boost on a car.
2. There seems to be several different ways of hooking up speakers on the back of the unit, maybe one way is less likely to burn out a low power rated driver.
............................................................
Kenwood KA-9X info anyone? - Page 2 - AudioKarma.org Home Audio Stereo Discussion Forums
KA9X
Kenwood KA-9X info anyone? [Archive] - AudioKarma.org Home Audio Stereo Discussion Forums
...................................................
Kenwood KA-9X | Owners Manual, Service Manual, Schematics, Free Download | HiFi Engine
............................................
KENWOOD KA-9X 9XG SM Service Manual free download, schematics, eeprom, repair info for electronics
............................................
Ideas:
1. The amperage/voltage spikes provided for musical peaks from the staged amps are too much for the drivers. Perhaps the power jumps in too fast or something like a turbo boost on a car.
2. There seems to be several different ways of hooking up speakers on the back of the unit, maybe one way is less likely to burn out a low power rated driver.
............................................................
Kenwood KA-9X info anyone? - Page 2 - AudioKarma.org Home Audio Stereo Discussion Forums
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
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well, some mixed Brit on mom's side and ukapolaranian on dad's -does that explain anything?
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Joined 2009
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Seems like a reasonable response from Lowther to me.
good suggestion to look for dc offset.
I wonder if there is any chance it was oscillating and fried the drivers with r.f. ?
good suggestion to look for dc offset.
I wonder if there is any chance it was oscillating and fried the drivers with r.f. ?
Come on, let's keep it simple !
Hey guys, rather than looking for rather far fetched reasons, please be aware that the wire they use is one tenth of a millimeter thick. Aluminum copper plated.
how do you expect to run 100 watts in such gauge ?
the Kenwood has some circuitry to check for DC and it works.
The first time it fried was with a triode amp with no DC danger.
I tend to think it is rather funny to dare state that the amp 'turns out too much ampage and not enough voltage': have they heard about Ohm's law ?
Now let them sell as much as they can but let alos the eventual customers know the underside of the game.
Hey guys, rather than looking for rather far fetched reasons, please be aware that the wire they use is one tenth of a millimeter thick. Aluminum copper plated.
how do you expect to run 100 watts in such gauge ?
the Kenwood has some circuitry to check for DC and it works.
The first time it fried was with a triode amp with no DC danger.
I tend to think it is rather funny to dare state that the amp 'turns out too much ampage and not enough voltage': have they heard about Ohm's law ?
Now let them sell as much as they can but let alos the eventual customers know the underside of the game.
Forget the Lowther power rating on their page, 100 Watts is just ridiculous, every one knows that. 6 watts is about what it takes to burn the Lowther. But at 6 watts they are so painfully loud and horribly distorting, that I woulder why would anyone ever need to play it so loud. If loud is what you want, use PA drivers. How fast you burn the Lowthers depends how much low frequencies are you feeding it with. If you even use eq and add an extra bass to compensate for Lowther complete lack of bass, you burn them even easier. On the other hand, if you accept that Lowthers are only midrange drivers with some high frequency extension (an lots of problems in this area), and you run them with subwoofer, you can actually push them quite hard and they can wistand a lot of punishment. (I did some parties with Lowthers, not recommended).
It is possible you may have a dc offset problem with your amp.
Regarding the coil, how can you have a paper coil? The coil has to be electricaly conductive.
Having known Chris for a number of years, I find that this explains everything.
BTW: In what Galaxy is the Ukapolaranian Planetary System found?
Best Regards,
Terry "Captain Kirk" Olson
I am not sure what happened with your Lowthers. But I can tell you that I have been using Lowther drivers for almost 10 years and have run them using several different 200 watt SS amps without any issues. They have been played both loud and soft without any problems. They have survived a couple of severe transients when some idiot (me) turned on/off an active crossover with the amp still powered up, the amp should be last on and first off. Lowther drivers are more robust then I ever imagined, if you have fried several of them then you might want to re examine your set-up to see if you can figure out why.
Martin
From a guy with LOTS of Lowther experience
Yes, the wire will fry at about 3 amps. I have done this. The 100 watt power rating is based upon an occasional peak, not running a continuous 100 watts. Just like running 100 watt 20 kHz note through virtually any hi-fi speaker will fry the tweeter. There has to be a little common sense here. Yes, you can use a 100 watt amp, that is what they mean. It works just fine. When you hear the speaker start to distort, compress, and sound distressed, you are too loud. Nothing you should not do with any speaker.
The former is paper, the voice coil is aluminum wire. Using the proper names makes things clear.
Your amp is mis-behaving. Either DC offset, or large turn on transient, or oscillation in the ultra-sonic region. The driver will not over-heat and the voice coil be ruined unless you seriously mistreat it. It would be better if you complained to the amp manufacturer that they fried your Lowthers, than complaining about the Lowthers being fried by a bad amplifier.
I am sorry for your troubles, and of course wish that it could be fixed easily by a change in the Lowthers. But in the meanwhile, put a 1 amp fast blow fuse in line with your speakers, and you will protect the speakers. Plan on changing the fuses often until you get the amp fixed.
Yes, the wire will fry at about 3 amps. I have done this. The 100 watt power rating is based upon an occasional peak, not running a continuous 100 watts. Just like running 100 watt 20 kHz note through virtually any hi-fi speaker will fry the tweeter. There has to be a little common sense here. Yes, you can use a 100 watt amp, that is what they mean. It works just fine. When you hear the speaker start to distort, compress, and sound distressed, you are too loud. Nothing you should not do with any speaker.
The former is paper, the voice coil is aluminum wire. Using the proper names makes things clear.
Your amp is mis-behaving. Either DC offset, or large turn on transient, or oscillation in the ultra-sonic region. The driver will not over-heat and the voice coil be ruined unless you seriously mistreat it. It would be better if you complained to the amp manufacturer that they fried your Lowthers, than complaining about the Lowthers being fried by a bad amplifier.
I am sorry for your troubles, and of course wish that it could be fixed easily by a change in the Lowthers. But in the meanwhile, put a 1 amp fast blow fuse in line with your speakers, and you will protect the speakers. Plan on changing the fuses often until you get the amp fixed.
That particular amplifier has an unusual topology called "Sigma Drive" which is a feedback sensing or modulating circuit of some kind. The amp came with special speaker cables to enable the function. The cables look similar to biwire cables, with one clearly larger than the other, only hooked up "backwards" (ie two connections at the amp, one at the speaker (per terminal), with the smaller gauge cable to the Sigma sensing connector on the amp).
Some owners suggest that the Kenwood OEM cables were a certain "known configuration" so that you should not try to DIY your own replacements.
If you use conventional speaker cables, be sure they are hooked up at the correct amplifier terminals. Apparently, hooked up properly, the Sigma Drive function is disabled with conventional cables.
Call me crazy, but I would be looking at the service manual for the Kenwood for some clues, and of course be careful that that the unit is functioning correctly.
Checking for DC offset would be a good idea, but the Sigma Drive thing might complicate the procedure over normal ... just a guess, though.
Certainly knowing more of how the Sigma Drive principle works on this amp would be helpful ... there are many things you can say about variable feedback, but one thing for sure is instability, possibly in the frequency range above 20 KHz, is definitely a possibility. With the current this amp can swing (170W into 4 ohms), that could mean large voltages appearing at the driver.
As for power handling guidelines, these are not hard-and-fast rules intended to be tested with 20 Khz sine waves, on any speaker. 100W program means 10 watts average with music, which will not have significant HF power in any case even at that average level. This is not unique to Lowthers.
Possibly not an issue, assuming the amp is functioning correctly, but if it's not? I would either use a more conventional amp with these speakers (my personal choice), or have the amp checked thoroughly before I tried it again (perhaps yours).
Finally, and this is just my personal opinion (and you haven't asked for it, so you can take it or leave it), I would also suggest that Lowthers are not for everyone, and perhaps you are one of those people they are not best suited for. My advise is to fix them and sell them, or sell them as-is to someone who would fix them, and try something else more suited to your listening habits.
Some owners suggest that the Kenwood OEM cables were a certain "known configuration" so that you should not try to DIY your own replacements.
If you use conventional speaker cables, be sure they are hooked up at the correct amplifier terminals. Apparently, hooked up properly, the Sigma Drive function is disabled with conventional cables.
Call me crazy, but I would be looking at the service manual for the Kenwood for some clues, and of course be careful that that the unit is functioning correctly.
Checking for DC offset would be a good idea, but the Sigma Drive thing might complicate the procedure over normal ... just a guess, though.
Certainly knowing more of how the Sigma Drive principle works on this amp would be helpful ... there are many things you can say about variable feedback, but one thing for sure is instability, possibly in the frequency range above 20 KHz, is definitely a possibility. With the current this amp can swing (170W into 4 ohms), that could mean large voltages appearing at the driver.
As for power handling guidelines, these are not hard-and-fast rules intended to be tested with 20 Khz sine waves, on any speaker. 100W program means 10 watts average with music, which will not have significant HF power in any case even at that average level. This is not unique to Lowthers.
Possibly not an issue, assuming the amp is functioning correctly, but if it's not? I would either use a more conventional amp with these speakers (my personal choice), or have the amp checked thoroughly before I tried it again (perhaps yours).
Finally, and this is just my personal opinion (and you haven't asked for it, so you can take it or leave it), I would also suggest that Lowthers are not for everyone, and perhaps you are one of those people they are not best suited for. My advise is to fix them and sell them, or sell them as-is to someone who would fix them, and try something else more suited to your listening habits.
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If you don't have a dc offset problem. You are almost guaranteed to have an oscillation problem, as others have suggested.
The other possibility is poor manufacturing of the speakers and they are not admitting fault.
Hopefully you are not using fancy speaker cables. These indeed can cause oscillation also.
The other possibility is poor manufacturing of the speakers and they are not admitting fault.
Hopefully you are not using fancy speaker cables. These indeed can cause oscillation also.
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