twelveblocks Posted December 23, 2012 Share Posted December 23, 2012 Could my amp clipping incident have damaged one of my speakers? The highs on that speaker that got clipped just don't sound right, and my son even hears it too (he's a musician with a good ear). The bass and low end sound great in both. Is there something I need to do to them after 17yrs of fairly heavy use? Side note: The amp is a little stronger now. Thank you. Quote Link to comment Share on other sites More sharing options...
djk Posted December 23, 2012 Share Posted December 23, 2012 The HF driver in those is really hard to hurt, although they do suffer total failure from time-to-time from the BeCu leadout wires. If you are still having problems I would swap the outputs of the amp to rule it out, and if still an issue I would swap the HF horns from speaker-to-speaker. If there is a problem with the driver it should show up. If there is a problem with the same speaker it will most likely be with the network , an easy fix for someone like forum member BEC (or others that have a good LCR meter), and should be inexpensive to repair (a lot less than a diaphragm would be). If the network is the problem, refurbish both of them with identical parts to preserve their imaging. If the driver is the problem, send it to BEC to be refurbished (this specific driver is not one I would recommend most people try and work on). Quote Link to comment Share on other sites More sharing options...
moray james Posted December 23, 2012 Share Posted December 23, 2012 Yes clipping sure could have damaged your diaphragm. Try switching speaker connections at the amp to see if the problem trades channels. If it does the problem is your amp if the problem stays with the speaker then yes in all likelyhood you have a damaged diaphragm. Bob crites can either sell you a new one but I highly recommend that you send the damaged driver to Bob an let him switch out for a brand new factory original diaphragm you will be good as new. Unless you have experience with this driver it (the diaphragm) is easily damaged. Warmest wishes for the Christmas season and a warm welcome to the forum. This is a very special place. Best regards Moray James. Quote Link to comment Share on other sites More sharing options...
djk Posted December 24, 2012 Share Posted December 24, 2012 "Yes clipping sure could have damaged your diaphragm." I am tired of hearing this repeated by all when it is not true. The reason clipping with a small amplifier may damage a tweeter is because of the increase in average power during the un-clipped portion of the program material, not the increase in power during the clipped portion of the program material. The other reason it may cause damage has nothing to do with clipping either, and that's mechanical damage. Cone motion increases at a 12dB/oct rate at lower frequencies, as does the low frequency content of program material. This increase in cone motion causes the lead-out wires from the voice-coil to the terminals of the driver to flex, work-harden, and fracture (and fail). Clipping a poorly designed amplifier can cause amplifier instability problems that can lead to speaker problems. This usually takes the form of mechanical damage to the woofer, not the tweeter. The 'soft-clip' circuit in NAD amplifiers is actually a hard clipper circuit on the input to the power amplifier. It clips the input signal so that the feedback loop in the amplifier does not clip. When viewed on an oscilloscope the clipped audio waveform looks the same with the circuit on or off. Installs in clubs with Klipsch and NAD were run into clipping for hours on end, with no problems (after fixing some AL networks that were defective and only had a 6dB slope on the tweeter). In summary, clipping only causes damage from either an increase in average power, or from mechanical damage. Quote Link to comment Share on other sites More sharing options...
twelveblocks Posted December 25, 2012 Author Share Posted December 25, 2012 Thanks for your reply, I'm swapping outputs tomorrow but I'm starting to think I'm chasing a ghost. Maybe my ears need to adjust to the new power. Would it be worthwhile to check the networks anyway being since they're 17yrs old? Quote Link to comment Share on other sites More sharing options...
twelveblocks Posted December 29, 2012 Author Share Posted December 29, 2012 Thank you, moray james. Klipsch tech support did email me back when I first encountered problems: "It sounds like you may be reaching the limits of the tweeter and/or your amplifier is clipping which can cause damage to any speaker high-frequency drivers." So, Klipsch agrees with you that damage may have occurred to my HF driver. I swapped the connections at the amp and that right ch. speaker still sounds "harsher" in the highs than the left ch. How do I know if it is a damaged driver vs a crossover that needs repairing? I work in health care and I'm not comfortable taking apart my speakers. I contacted a local guy for speaker rebuilding, he thinks "I've been reading too much" and I should break in my rebuilt amp before addressing the speakers. He said he could upgrade the crossovers for $400/pr., but didn't seem eager to do so. I am interested in Mr Crites's work with Klipsch speakers, which I can afford much easier than a new set. I just don't know enough to be confident I'm sending him the right parts to repair/rebuild. I will contact Mr. Crites and see what advice he may offer. Thanks again for your help, moray james. Best regards, Miles. Quote Link to comment Share on other sites More sharing options...
moray james Posted December 29, 2012 Share Posted December 29, 2012 Hey Miles: Dennis is technically right. Most of the time the damage is caused by smaller amps which are driven into sustained distortion. This causes a rapid build up of heat which is normally what fries things or the amp clips in a hard way and that throws the temp of the VC over the top and it melts. This is the main reason why larger amplifiers are safer to run than smaller ones. Are you willing to use a screw driver and swap the horns? There are only two spade connectots inside on the horns. You will want to use some tape to identify the colored connector terminal (one terminal will have a black wire which is ground the other terminal will have a colored wire which is positive so flag the colored terminal). Trade one horn for the other. This is a simple straigh forward proceedure. If the harsh sound follows the horn then the problem is with the voice coil of the diaphragm. If the harsh sound stays with the original offending cabinet then the issue is with the crossover. If the problem turns out to be the crossover I would suggest that you send both boards in to Bob Crites and have him upgrade all the caps. These loudspeakers are more than old enough to justify having new capacitors installed. Your speakers will sound better than they did when they were new. Please keep us posted as to what you find. Bob is your sole commercial source for factory original diaphragms for the K63KN driver. I hope this helps. Best regards Moray James. Quote Link to comment Share on other sites More sharing options...
twelveblocks Posted December 30, 2012 Author Share Posted December 30, 2012 Are the spade connectors soldered to the horn driver? I am going to switch them when I get a chance. Is my amp too small for the speakers? About the loudest I turn up the preamp's volume is well under halfway, and a quarter is usually enough to fill the house. It did a great job until Sept. when a cap started leaking, which started this whole thing. Parasound rebuilt the amp and my volume control is more sensitive now. Thanks again for your advice, I appreciate it. Have a Happy New Year. Quote Link to comment Share on other sites More sharing options...
moray james Posted December 31, 2012 Share Posted December 31, 2012 The spade connectors ar not soldered they are quick connect together or apart by hand easy. I guess that I missed the part about your amp having to be rebuilt. Simply do as suggested and you will know where the problem lies. Once you determing the problem you can decide upon your course of action. It is so have a happy new year you speakers will soon be repaired either way and that will be worth celibrating. Best regards Moray James. Quote Link to comment Share on other sites More sharing options...
twelveblocks Posted February 6, 2013 Author Share Posted February 6, 2013 My speakers are back, they sound bright, clear and powerful again. I sent my speaker networks to Bob and Michael Crites for a rebuild, and I put them back in last week. What a difference it made in sound quality-- my son and another friend were both struck by the difference. Thank you Moray James for your advice and motivation, I have my music back. Miles Quote Link to comment Share on other sites More sharing options...
moray james Posted February 6, 2013 Share Posted February 6, 2013 Miles: that is great congratulations are in order. I am sure that you feel fantastic and you now have your entire music collection to re discover all over again anew as if for the very first time. See if you can raise your CF2 up so that the centre of the mid horn is at your seated ear level which is usually in the 36 -39 inch range depending on how tall you are and your seating. Great speaker have fun and don't stop. Best regards Moray James. Quote Link to comment Share on other sites More sharing options...
Marvel Posted February 6, 2013 Share Posted February 6, 2013 I sent my speaker networks to Bob and Michael Crites for a rebuild, and I put them back in last week. What a difference it made in sound quality-- I would guess it also didn't cost $400 for the pair, either. Glad you can enjoy the music again.Bruce Quote Link to comment Share on other sites More sharing options...
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