33116
From: ryan, [woh-65-28-247-229.woh.rr.com]
Subject: is it possible to ruin your subs buy underpowering them??
| i was wondering if one were to underpower there subwoofers if they would ruin the subs??? I was thinking about hooking my subs up in my room.. untill my new car comes in.. but my stereo doesnt put out near the power to meet the rms of both subs.. would this ruin my subs?? |
Responses:
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33141
From: Richard Greene, [frasier.ford.com]
Subject: No it's not possible (lower power = less risk of damage)
|
Voice coils can only be damaged by too much power. Amplifier voltage clipping is not relevant for subwoofer voice coils. Bass sound quality might not be optimum but the voice coils only care about voltages, not sound quality. |
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33148
From: Brian Owens, [page.paccar.com]
Subject: Re: No it's not possible (lower power = less risk of damage)
URL: my webpage. . .
|
Hey Richard. . . .Long time since you have been around here!!! how are things at Ford? it has been 2 years since I left there and I sure do miss it!! Question for you: While the voice coil may not be burned by clipping, I always thought damage could still come from the driver cone moving out of control as the wave form was cut at the peaks and started to look like DC. coil rubbing, spider damage, surround damage. I guess these problem would also depend on the box design (actual mechanical power handling vs. thermal power handling), but sending a clipped signal to the driver does not help . . .not true? thanks! Brian |
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33155
From: Richard Greene, [frasier.ford.com]
Subject: Effect of clipping on subwoofers ... and tweeters
|
Too much power for too long can damage any voice coil. Tweeters are especially vulnerable due to lightweight thin wire voice coils needed to keep cone mass low. If there is frequent amplifier clipping, the cause is 90-95% the person who last touched the volume control and 5-10% amplifier clipping harmonics when a tweeter blows. For woofers (and for tweeters when there is no clipping) the cause is 100% the person who last touched the volume control when a driver blows. However it is easier on the ego for that person to blame the amplifier! I hate to blame amplifiers for driver damage! YOU WROTE: "I always thought damage could still come from the driver cone moving out of control as the wave form was cut at the peaks and started to look like DC. coil rubbing, spider damage, surround damage. " RG Overexcursion damage is possible and the more powerful the amplifier, "the more possible it is"! Sealed enclosure speakers are less vulnerable than ported speakers. There is no DC current. Clipping the peak AC voltages actually sends less power to the subwoofer ... but if you keep increasing the volume control after clipping begins, the sound gets more and more compressed and the average power output continues to increase even though peak voltages can't increase. . . . YOU WROTE: "I guess these problem would also depend on the box design (actual mechanical power handling vs. thermal power handling), but sending a clipped signal to the driver does not help . . .not true?" RG The subwoofer driver doesn't care about the clipping harmonics ... just too much voltage from the amplifier for too long and voice coil adhesives melt ... and then the wires break. ... I guess you could say a clipped signal has compressed dynamics and that means a higher average power level (like a TV commercial --consistently loud) which is more dangerous ... but then compressed bass also sounds LOUDER so maybe you wouldn't turn the volume control as high if an amp was clipping (versus a non-clipping amp)? Clipping is typically intermittent "flat topping" of bass or lower midrange transients in music. There are clipping harmonics that add distortion to the tweeter's output without one touching the volume control ... but this only happens when there is clipping ... so constant clipping of a sine wave test tone would be the worst case. Fortunately the clipping harmonics only add about one watt extra power to the tweeter's voice coil. In the old days when paper cone tweeters could not handle much power one more watt was much more dangerous than it is today when even cheap dome tweeters can handle 10 or 20 watts through their high-pass filters. There is no DC current. The driver's cone does not stop moving. If a tweeter can handle 20 watts power than it's possible a 20wpc amplifier can end its life if played LOUD enough for long enough. I guess that means any amplifier can damage a tweeter. Subwoofer drivers can handle a lot more power although maybe less than they are rated for. Some amplifiers will not be powerful enough to damage a high-power handling subwoofer driver played at maximum output indefinitely, whether there is clipping or not. If a sub driver can handle 200 watts power then any amplifier rated at more than 100wpc could damage the voice coil. I'm assuming the amp is capable of +3dB over rated output (typical of a decent amplifier, believe it or not, although distortion would be out of spec and quite high at the +3dB point). |
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33172
From: djk, [tc077.cedar-rapids.net]
Subject: Amplifier Feedback
|
99.999999999% of amplifiers driving subs have feedback. When the amplifier clips this can destroy the woofer. It has to do with the time constants in the power supply and feedback loop of the amplifier. Watch the motion of the subwoofer cone at cliping, it will generally have a 1~2 hz component to it. It is this 1~2 hz component at rail-to-rail output (cliping) that causes the destruction of the driver. An interesting case: JBL B380 subwoofer, 2235 driver, a 6th order equalized system tuned to about 23hz. While this sub can handle in excess of 1KW un-distorted power on music, the 100W Adcom GFA545 will slam the spider into the top plate of the magnet when the amplifier clips (due to the 1hz~2hz component). Crown builds a circuit into their top-of-the-line VZ5000 to prevent this, they call it a 'loudspeaker off-set integrator'. It's complicated, and an integral part of the amplifier design. Speaker companies are aware of the problem, but don't really know how to deal with it. They generally just recommend using a 'good' amp rated at about double the RMS power of the loudspeaker and hope it doesn't clip too hard or too often. The real answer is to make sure the feedback loop of the amplifier never clips. A 'hard limiter', think DBX, is a common solution. A hard input clipper is better. If you hard clip the input of the amplifier at a level just before the amplifier would clip, then the feedback loop of the amplifier will always be under control and not do anything nasty. There is a brand of amplifiers that have switchable diodes on the input of the amplifier to hard clip the input signal. NAD Except the call it 'soft cliping'. (Would anybody use it if it was called 'hard cliping'?) I don't think anyone at NAD really understands what this circuit does for the loudspeaker, nor is it common knowledge elsewhere. |
Responses:
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33378
From: Adrian Mack, [dialup-196-97.wasp.net.au]
Subject: Right on!
URL: My website, Peerless XLS 12 Dual PR Sub Project, 18LW1400 vented sub, Horns, etc.....
|
Hey DJK! I think your right about the DC component after talking to a mate of mine taking an Electrotechnology course. I would like for you to read the post I've made, as I think your right on the money. See http://www.diysubwoofers.org/talkshop/messages/33377.htm as it describes whats happening, and make any further comments if you wish! Adrian |
33431
From: norman bates, [oproxy4.rockwellcollins.com]
Subject: isn't he just that good !!!!!!!!!!!!!!!!!!!!!!!!!(NT)
| (NT) |
Responses:
None
33413
From: Richard Greene, [ncecc2.ford.com]
Subject: Rane Corp. white paper on amplifiers and clipping
|
The paper is from a pro sound point of view where high SPL is the primary goal and clipping distortion is likely to be ignored until something breaks! -- that concept helps sell Rane limiters. ... But home audiophiles are unlikely to tolerate levels of clipping that would be tolerated in pro sound. Severely clipping a 100Hz. square wave with a 100wpc amplifier: 1.1kHz. harmonics were calculated as 0.83 watts 1.3kHz. harmonics were calculated as 0.589 watts -- Higher level harmonics were not shown on the chart (Note: As the frequency increases, the level (watts) of clipping harmonics decreases) because a 1.0 kHz. turnover frequency was assumed (home audio typically uses a one or two octave higher turnover frequency for tweeters) and those clipping harmonics shown on the chart (1.1kHz. and 1.3kHz.) are just above the 1.0kHz. turnover frequency = the most powerful and most dangerous clipping harmonics resulting from the 100Hz. test tone ... and they only added up to 1.4 watts ... and 1.4 watts is not going to destroy any tweeter! |
33438
From: djk, [tc060.cedar-rapids.net]
Subject: Average Power Increase
|
That Rane article on how the increase in average power from clipping is what burns out tweeters is great. "... But home audiophiles are unlikely to tolerate levels of clipping that would be tolerated in pro sound." Maybe, OTOH the average listener thinks an amplifier driven 6dB into clipping sounds fine. When I ask these people to set the volume control at the onset of distortion, it ends up about 10dB into clipping(I kid you not!). I found on the typical stereo rig that if you fused the speaker input for 1/4 the rated amplifier wattage that you got rid of 90% of the tweeter failures. On most program material this was 6dB~10dB into clipping. |
Responses:
None
33429
From: Adrian Mack, [082.pth0604.pth.iprimus.net.au]
Subject: Re: Rane Corp. white paper on amplifiers and clipping
URL: My website, Peerless XLS 12 Dual PR Sub Project, 18LW1400 vented sub, Horns, etc.....
|
Hi Richard! Seems like it never ends ey! I guess theres just so many opinions out there, like the time alignment guys - some of the things they suggest, others will just completely ignore. I guess the amount of upper harmonics would depend on how severly the clipping is. Its probable that extreme clipping is the case where we should be concerned, and not small amounts of clipping where damage might not occur. But theres one thing we can agree on - dont let the amp go into clipping, weather or not its because it sounds crap, or if it does any damage. To me, both are good enough reasons not to do it! Adrian |
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33379
From: Derek, [pool-64-222-48-216.prov.east.verizon.net]
Subject: Adrian!!
| hey adrian did you ever take a look at my last post about the peerless subs? if you havent can u please and let me know what u think i need your help!! lol :) |
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[33381]
33381
From: Adrian Mack, [006.pth0201.pth.iprimus.net.au]
Subject: Have not forgot about you
URL: My website, Peerless XLS 12 Dual PR Sub Project, 18LW1400 vented sub, Horns, etc.....
|
I havn't forgot about you! I've just been rather busy, so I've only been answering the interesting posts, such as the thread on clipping and the thread on distortion. But anyhow, I've made you a reply called "Box tuning for Peerless XLS 10" in our original thread regarding this woofer. Adrian |
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33246
From: Richard Greene, [frasier.ford.com]
Subject: Any examples for DIY subwoofers used in homes?
|
It seems than no two audiophiles agree on the effects of clipping. I believe the original question was about driving a car subwoofer temporarily with a home stereo receiver or amplifier (wpc not mentioned). In my mind was 50wpc because it's tough to find a less powerful receiver these days. I believe the risk to the subwoofer is very low even if bass transients in the music were clipped fairly often. What you described does not seem like the typical clipping experience at home (intermittent and related to bass transients in the music). I surveyed people who build speakers / subwoofers but unfortunately their experiences matched mine -- damaged tweeters, but not woofers. I searched the internet for experts who would support your claim that clipping is far more dangerous to home subwoofers (or any woofers) than excessive rms power but could not find any. Perhaps you have a link or two? What you described sounds like what could happen if one drove a ported subwoofer (with no high-pass filter or other protection circuit) with a 30wpc amplifier playing a 50Hz. sine wave with the volume control of the pre-amp at, or close to, full volume. Could any listener remain in a home listening room with the bass so loud, compressed and distorted? Taking your post to the extreme: - Assuming the owner's top priority is to avoid damage to his "200 watt power handling" subwoofer driver used in a ported enclosure: If there was a choice of a 20wpc amplifier or 2,000wpc amplifier, which one would be more likely to cause damage to the subwoofer driver assuming the owner was able to completely ignores clipping distortion? |
Responses:
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33354
From: djk, [tc090.cedar-rapids.net]
Subject: JBL B380/BX63
|
The example I cited was the destruction of a JBL2235 woofer in a B380 enclosure with the BX63 electronic crossover, which has a 20hz 12dB/oct high pass filter. The 100W Adcom GFA545 when driven into clipping caused the spider to slam into the top plate and eventually destroy the driver. Substituting a bridged Crest3501, about 1KW on program material, behaved the same way, except it played about 10dB louder before clipping. Peak limiters work, if adjusted properly, but can make the system sound 'wimpy'. An amplifier with a hard clip on the input can play much, much, much louder than the same amplifier with a peak limiter. It's mainly a question of how much subsonic garbage your speaker alignment can handle, for vented systems it may not be much. The subsonic garbage is generated within the amplifier by clipping, so a filter doesn't do any good. Changing the RC time constant of the pole in the feedback loop to be higher than the RC pole formed by the power supply filter caps and the load impedance, and then adding back-to-back diodes across the feedback cap seems to take care of the problem. |
Responses:
None
33331
From: Richard Greene , [ncache1.ford.com]
Subject: Adire Audio comment on low power amp NOT damaging their sub driver
|
I own an Adire Audio Tempest 15" subwoofer driver so felt I would be entitled to ask whether driving it with a cheap 30wpc receiver could be dangerous due to clipping. Here's the e-mail response from Adire Audio Tech Support followed by my e-mail question: Richard, Thanks for the e-mail! A 30WPC channel amp won't damage a Tempest at all, regardless of clipping. On the other hand, a 300W amp clipped heavily could cook a Tempest quite easily. Clipping is a problem in that it can double the effective power delivered to the driver, and do it with a much more damaging spectrum. However, I think the 30WPC concern is a bit overzealous. Thanks again, Adire Tech Support ---Original Message sent to Adire Audio Tech Support---From: Greene, Richard Sent: Tuesday, August 05, 2003 8:37 AM To: 'techsupport@Adireaudio.com' Subject: Clipping dangerous to Tempest driver? While a more powerful amplifier is being repaired, would it be dangerous for me to use a cheap ($98) Japanese 30wpc receiver to drive a DIY Tempest ported Sonotube subwoofer? I expect with only 30wpc there will be amplifier clipping but I did not believe such a low power receiver could damage a Tempest driver ... until I read what a pro audio speaker expert posted on the internet -- his post suggests to me that a 30wpc receiver could be a "Tempest killer" even though the Tempest is rated at 750 watts power handling. Could you provide any comments on his warning quoted below: "99.999999999% of amplifiers driving subs have feedback. When the amplifier clips this can destroy the woofer. It has to do with the time constants in the power supply and feedback loop of the amplifier. Watch the motion of the subwoofer cone at clipping, it will generally have a 1~2 hz component to it. It is this 1~2 hz component at rail-to-rail output (clipping) that causes the destruction of the driver." |
33342
From: Adrian Mack, [dialup-196-181.wasp.net.au]
Subject: Tempest clipping of small and large power amps
URL: My website, Peerless XLS 12 Dual PR Sub Project, 18LW1400 vented sub, Horns, etc.....
|
Hi guys! Great discussion, djk and Richard! > A 30WPC channel amp won't damage a Tempest at all, > regardless of clipping. I dont think a 30WPC amp could damage a Tempest - its not great, but its OK. And the cones or voice coils arn't going to melt or anything if driven into clipping occasionally, especially with Tempest, it will probably just snicker at the prospect. My view has always been that the clipped part of the waveform is DC. I've read some things on weather its true, or not true, but thats my opinion anyway. I dont think theres a 1-2Hz component in a clipped waveform, as clipping is essentially harmonics, and most of this is midband, and in multi-way systems the midrange and tweeters are gonna die on hard clipping. I've just not heard of it before, so I cant say for sure, but thats how I see it though. Say an amp generates full power of 100Wrms at 3/4 power on the volume control, twist it to full power, will the amp be able to hit 200 watts for brief periods? The answer is, it probably wont. And it is likely to clip, which means it probably cant output much more than 100Wrms no matter how you mix the frequency ranges, it will just clip in the form of square waves, and these will be of higher order harmonics with most clipped energry distributed midband. But whatever the cause, either by preamp or the main amp, current gain suddenly goes from maximum gain provided by the amplifier - probably something like a million - to zero. There is no more gain. It doesn't really go to "zero" in that the amplifier is still providing more output current than input current. But it can go no higher, and the delta is then zero. But thats still not necessarily good news for the woofer though. I think that a bit larger amplifiers driven into hard clipping for extended periods could destroy the woofer. Or perhaps smaller amplifiers capable of deliver high peak voltages, and then clipping those. In any case, the 30WPC amp is likely not to do any damage to Tempest. That brings me to the second point, clipping is nasty. Just dont do it. Turn the volume knob down, or buy stuff that handles more power all the way around - speakers, amplifier, everything. Clipping introduces lots of higher order distortion, and that means it sounds crap, and I can tell you clipping is not something you want to be listening too. Buying a larger amp will mean the speakers wont clip anymore, and thats a good thing, but then of course, you can damage the speakers from too much power that they can safely tolerate, unless your fingers wont ever be tempted to nudge that volume control any further. To conclude, a 30WPC should be no problem with tempest, and it will just laugh at the site of clipping - the driver is capable of handling whatever this amp decides to do. Clipping is still bad though, and introduces lots of harmonic distortion, so it sounds real crap. But in terms of actual damage to the driver - theres none. Adrian |
33356
From: Richard Greene, [frasier.ford.com]
Subject: "You won't protect your speakers by using a larger amplifier"
|
From a Tom Nousaine post at the link below (not that easy to follow the very long UseNet discussion on the danger of clipping -- I read the entire thread and I can't say there is agreement ... but Tom does test speakers for a living, so I'll assume his opinion is an expert opinion: "The speaker never comes to a stop. This idea is a fundamental misunderstanding that comes from that "DC" argument. I think it stems from the misunderstanding that the analog picture of a sine wave or square wave as it appears on the face of an oscilliscope is actually the 'signal' and the flat top is some kind of DC component. That picture is just an analog idea or representation of the sound or signal. As Mark began by saying (in his paper) there is no DC component ... he's right .... and therefore the cone never stops. Another part of the analysis that tends to get forgotten is that the tweeter's impedance will be rising as well and the only important harmonics will occur around the resonance area of the speaker. All this is not a criticsm of the work (paper). The idea is well taken and right on the money. You won't protect your speakers by using a larger amplifier. It will just burn them out as fast by supplying more power no matter what the condition of the signal." TOM NOUSAINE quote from: http://groups.google.com/groups?selm=20020228221328.28778.00001881%40mb-fo.aol.com&output=gplain |
33375
From: Adrian Mack, [dialup-196-97.wasp.net.au]
Subject: Small vs Large powered amplifiers
URL: My website, Peerless XLS 12 Dual PR Sub Project, 18LW1400 vented sub, Horns, etc.....
|
Hi Richard! I'm beginning to doubt that the clipped component is DC too, I think from now on my take will be that the clipped portion is not DC. But the statement "You won't protect your speakers by using a larger amplifier" is not entirely true. I'm going to aim this post at the high frequency components - the tweeters, and not the sub-drivers as we've already discussed, they are much, less prone to damage than the rest of the components are in a multi-way system from clipping problems. Except maybe a 50 cent radioshack woofer :P [grin]. First off, we have the issue of energy distribution in the program material. Say we have a 50W speaker driven by a 50W amplifier, large 20db peaks can be damaging thermally and also by driver excursion-limitations depending on the nature of the program material. But I guess with music, this is a bit of a non-issue as the energy distribution in the treble region is typically 10 to 20db less than bass and midrange freqeuncies. So that means in our multi-way system, the tweeter is allowed to have a much lower power handling than the woofer component must handle. But back to the subject of real clipping; the power output of an amplifier is not set in rock. A full turn of the volume control isn't a true indicator of its output capabilities. Manufactures spec their amplifiers to a certain THD level - and this may even be at a half turn of the volume knob, where power output may be 100W at 0.5% THD. In this case, THD could be overdriven to produce 200W of power output to the speakers and so on. When this happens, the distorted output could very well be in the treble region which can kill the tweeters. This content is rich in harmonics (distortion). These are one of the main killers of tweeters, as these harmonics are damaging. They are of higher frequency multiples of the original signal, and therefore the high frequency component of a loudspeaker system must bear the burnt distortion - even if the original signal may have been generated by a bass guitar.  As an example, above is a picture of a pure sine wave signal with no overtones or distorted harmonics displayed on an oscilloscope. It can be reproduced safely by the amplifier, as visible the top and bottom are nicely rounded contours. The average power output is one-half the peak power output. But when the amplifier is overdriven, the contours are "clipped off" and results in a near-square wave, which means it has flat areas at the top and bottom limits.  Above shows the top and bottom clipped off and the resulting square wave signal. When this happens, average power approaches the peak power, and this will cause the amplifier to deliver up to twice its rated output to the high freqeuncy driver, which may not be able to handle the abnormal load. To quote JBL: "A higher powered amplifier however, can generate the required power levels without clipping". I think the quote is relevant, because the "main meat" of this post was material sourced from the JBL tech notes. This will allow the loudspeaker system to recieve program material containing a normal distribution of energy levels. Under these conditions with the higher-powered amplifier, it is unlikely damage to the high frequency driver will occur than with the smaller amplifier and its clipped signal. So theres a few things we can do in this situation. First off, just dont drive the amplifier into clipping. That means, keeping the volume knob down to safe levels. Second, is to purchase an amplifier capable of producing more power than you will need. Remember that a loudspeaker can require additionally up to 10 times the average power level for transients. This can mean, getting an amplifier with large reserve power which will reproduce these transients clearly. When an amplifier runs out of undistorted power, it is forced to exceed its design capabilities, producing dangerous power levels rich in high frequency distortion, which is a major killer of tweeter components. But of course one thing runs sort of counterproductive - to quote my last post, "you can damage the speakers from too much power that they can safely tolerate, unless your fingers wont ever be tempted to nudge that volume control any further". Thats the only reason the larger amp will kill a high frequency component. But if we got down to measuring a low-powered amplifier outputing a clipped signal, and larger-powered amplifier outputing a clean signal, and then measuring each ones power output so that each one is sending the same voltage signal to the tweeter that it can safely tolerate - the larger amplifier is less likely to damage the component. Adrian |
33408
From: Richard Greene, [ncecc2.ford.com]
Subject: Clipping harmonics not that dangerous
|
The clipping harmonics that pass through the high pass filter and reach the tweeter are unlikely to account for more than one watt -- that's going to be a small percentage of the total power needed to damage a tweeter's voice coil. Probably 5% to 10%. So I'll blame clipping harmonics for 5% to 10% of the damage ... but the harsh sound of clipping harmonics also gives listeners an incentive to turn down the volume (or at least not increase the volume) so this "warning" might save a tweeter (and offset the bad news of clipping harmonics). My general conclusion is an amplifier that's frequently clipping is slightly more dangerous than a non-clipping amplifier playing equally loud. One thing true about what the listener hears before a tweeter self-destructs, no matter what amplifier was used: the music was VERY LOUD ! |
Responses:
None
33377
From: Adrian Mack, [dialup-196-97.wasp.net.au]
Subject: About DC components in clipping
URL: My website, Peerless XLS 12 Dual PR Sub Project, 18LW1400 vented sub, Horns, etc.....
|
Hi DJK and Richard! I was talking today to a mate of mine who takes an Electrotechnology course at Otago Polytechnic in New Zealand. And it seems that DJK is right about the DC component, at least, he is in accordance with this person taking the course. They are using osciloscopes there, and the DC component made the cone on a test unit move instantly outward, very quickly. This could be related to when DJK made observations on the 2235H unit, and the 100W amp causing it to slam into the front plate. The clipped portion of the signal is DC, and the non-clipped is AC. The corner is where the AC bit joins the DC part. This component, as DJK stated, is 1-2Hz, and causes excessive cone motion. What will happen is the cone will stop for a split second when the clipped signal is applied, and this will continously happen as changes in the signal are infinitly occuring. If it was just DC forever - like a 3V DC battery, the cone should just stay there. If we vary it slowly 0v to 3v DC, the cone will move and should produce some sound. This is all rather mute however seeing as its not the entire waveform thats DC on a clipped signal. But its interesting though. This tends to make a speaker driven into clipping have poorer cone control too, being constantly "stopped" for split seconds, every split second. I've noticed this too, when using a 240Wrms plate amp on my 18LW1400 18" woofer - excessive cone motion, and rather uncontrolled too (AND ALSO A VERY AWFUL CLIPPING SOUND!). But back on with 1.3KW Lab Gruppen - the problem is gone. So its fair to say this component is death to the woofer - clipping a woofer, in extremes, is death if it hits the front plate. The ideas that DJK has described to prevent clipping are accurate. And djk, if you want to step in here to offer a bit more of an opinion - go for it! Adrian |
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33410
From: Richard Greene, [ncecc2.ford.com]
Subject: The cone does not stop due to clipping - there is no DC component
|
Engineers never learn anything useful in school! An oscilliscope is fine for studying sine waves but not complex waveforms like music. But even a clipped sine wave is not a square wave. And no one listens to square waves or sine waves anyway except to make measurements at low volumes. I wish a subwoofer cone had the ability to stop moving instantaneously but it does not stop when listening to music. I suppose you could connect a battery to the driver and move the cone to one side or another. |
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33186
From: Brian, [206-48-63-219.caribsurf.com]
Subject: Re: Amplifier Feedback
|
Interesting scenario. However, it sounds like you're referring to (1) a vented system (sealed systems will exercise more control over the driver at low frequencies) and (2) a driver where the suspension does not prevent the former from hitting the backplate. I'm surprised that the JBL 2235 falls into this category. Wasn't the 1200GTi based on the same magnet structure? I was never able to get that driver to bottom out, using car audio amps from a JVC 60x2 upwards. |
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[33187]
33187
From: djk, [tc114.cedar-rapids.net]
Subject: Re: Amplifier Feedback
|
Like you say it's mainly a vented system problem. I think the spider is the main culprit. The 600W rated 2240 18" seems to have a big time problem with this, this is their 30hz Fs cloth edge job. |
Responses:
None
33149
From: Brian Owens, [page.paccar.com]
Subject: Re: No it's not possible (lower power = less risk of damage)
URL: my webpage. . .
|
Let me add that I am not talking about driving 15 watts to a 250 watt driver, but if you were near the driver's actual power limits. Brian |
Responses:
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33121
From: DSP-Freak, [213.142.92.36.adsl.gk.tiscali.no]
Subject: Re: is it possible to ruin your subs buy underpowering them??
| It'll be ok aslong as you don't overdrive your amps so they start clipping. So if you go easy on them it won't do any harm =) |
33127
From: ryan, [woh-65-28-247-229.woh.rr.com]
Subject: but i wont have my amp hooked up with the subs
| it will be in my room.. so my amp will not be powering the subs.. the subs will just be powered by my stereo |
33128
From: Derek, [pool-64-223-45-242.prov.east.verizon.net]
Subject: Re: but i wont have my amp hooked up with the subs
| so they will be having a full range sound sent to them ? wont sound good at all. |
33130
From: Chris Johnson, [prx3.vicdir.schools.net.au]
Subject: Re: but i wont have my amp hooked up with the subs
| you can get a sub cross over from almost anywhere, and they are pretty cheap too. |
33131
From: ryan, [woh-65-28-247-229.woh.rr.com]
Subject: Well i just want to make sure there working right
| i was just going to plug my subs into my stereo and play them for a little bit and make sure they are working right. but if underpowering them could put a risk at ruining them.. then i wont do it |
Responses:
[33139]
33139
From: Brian Owens, [page.paccar.com]
Subject: Re: Well i just want to make sure there working right
URL: my webpage. . .
|
As said above, just don't turn the volume up so that the outputs of the receiver clip. You could damage the woofer AND the receiver. They will sound bad if you do not get a crossover, but if you are just wanting to try them out, it willnot hurt them. Brian |
Responses:
None
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