SDA SRS drivers popping at high volume

joeparaski

I thought these speakers could handle up to 1,000 watts. But when I'm pumping the volume, the drivers start making popping sounds and I've gotta reduce the volume before I blow them. I tried several different amps and it did the same thing.....tried my Phase Linear 200 wpc, the 350 wpc, and an SAE 300 wpc. Did it also in single amp mode and in bi-amp mode.

Do any of you SRS owners play it loud enough to have this problem?

george daniel

possibly the polyswitch's have been tripped.after you turn the volume down do they reset?

Dennis Gardner

I just blew one of my mids on my SDA1Cs about a month ago with some particular driving bass guitar music. I heard the mid popping, took off the grill and just as I did, the driver jumped out of the voice coil groove and stuck in place. Returning it back into groove resulted in scraping the side of the coil, so I had to replace it. I'm not sure why these old models can't handle the watts they are rated for, but my guess is that they are simply tired.

I wasn't even at 12 o'clock on my preamp, so I guess around 150 watts on the peaks took mine out.

george daniel

after I rebuilt/upgraded my 1c x-overs,8-9 oclock is plenty loud for me

joeparaski

george daniel wrote:

possibly the polyswitch's have been tripped.after you turn the volume down do they reset?

No the switches did not trip....they just made a horrible popping sound.

Dennis Gardner

anonymouse wrote:

Man my ears would bleed at those levels. MY 1C's are plenty loud at very low wattage.

C weighted about 95-100dbs on my spl meter @ 8 feet away is when it started popping.

george daniel

uh-oh,like Dennis said,probabaly a mid or two.

heiney9

Gentleman, it's called clipping. Joe, you run alot of processors which really adds alot of distortion.

joeparaski

Ahhhh....but i thought of the "processor" stuff too, just in case that contributed to the problem. I bypassed everything and went straight from cd to pre-amp to amp and it still did it.

Isn't "clipping" something that the amp does rather than the speaker?

heiney9

joeparaski wrote:

Ahhhh....but i thought of the "processor" stuff too, just in case that contributed to the problem. I bypassed everything and went straight from cd to pre-amp to amp and it still did it.

Isn't "clipping" something that the amp does rather than the speaker?

Yes it's the amp. I'm too tired to explain tonight. We've recently discussed this in another thread. I'll revisit the explanation in the morning.

H9

heiney9

Here's a quick link

http://www.polkaudio.com/forums/showthread.php?t=38407&highlight=clipping

F1nut

heiney9 wrote:

Gentleman, it's called clipping.

Highly likely. Another issue may be that those amps just don't control the drivers very well. FYI, the polyswitches have nothing to do with the mids, only the tweeters and tweeters don't make popping noises.

I've pushed my 2.3TL's at times to between 110dB to 115dB with a peak of 117dB with no problems other than my ears ringing.

Polkersince85

Just to make sure, check to make sure that the cabinets are still sealed. Remember those "fluid coupled" thingy things. May be trying to drive them to the moon.

gyusher

You are over extending your woofers. . . Turn the bass down, come up gradually on the volume. . . Power is what is doing this, too much power. . . I think we all know that 1000 watts continuous is a whole lot of power. I doubt that you can deliver that much power to two speakers on a 15 or 20 amp house current circuit without tripping the breaker.

A high damping amp will help but in no way should you need that much power. . .If so then consider Pro gear or sound reinforcement speakers where they are designed for those extreme SPLs. . .

george daniel

I've pushed my 2.3TL's at times to between 110dB to 115dB with a peak of 117dB with no problems other than my ears ringing.[/QUOTE]

Jesse, I'm curious,,what are you driving them with? :eek:

amulford

Your bottoming out, clipping on the low end. Cut back on the bass a little. And get rid of some of the extra signal processors.

They'll take 1000 watts, with no problem. It just has to be clean.

heiney9

gyusher wrote:

You are over extending your woofers. . . Turn the bass down, come up gradually on the volume. . . Power is what is doing this, too much power. . . I think we all know that 1000 watts continuous is a whole lot of power. I doubt that you can deliver that much power to two speakers on a 15 or 20 amp house current circuit without tripping the breaker.

A high damping amp will help but in no way should you need that much power. . .If so then consider Pro gear or sound reinforcement speakers where they are designed for those extreme SPLs. . .

I have to disagree here. Yes the woofers are being over extended and perhap the bass is turned up too loud, but it's not too much power doing this. Something is clipping the signal coming out of the power amp. It's a fairly rare occurance to have this kind of clipping because usually it affect the tweeters and the poly swithces will kick in to let you know to turn it down before the mid-bass drivers start popping.

It is possible you have a bad driver because of age and it popped prematurely. When I sold Polks back when the SDA's, original Monitor's and RTA were new I always had customers, mostly younger kids, who listened to rock come in and mention this problem. It was from either way too much bass boost or too little power. We all think of clipping as what affects tweeters, but it can affect other driver as well.

You guys must be listening at insane levels. I turn my RTA's up on occasion and the output gets unbearable long before I pop a woofer or the poly-switches trip. I suppose to really give a good answer we need to know more about the situation. What music? Tone settings? How loud? What processors? Usually a mid-woofer will pop once or twice and if you get it turned down soon enough there is no permanent damage. But if you gave it a good thump it maybe toast.

Also don't rule equipment out entirely. Joe I know you run some older stuff that you mentioned (I believe) has given you some trouble lately. That could be the culprit in your case.

SDA's are starved for good clean power and they can take it. In your case the power isn't clean enough....for whatever reason.

H9


H9

heiney9

Actually Joe, I went back and re-read your 1st post and the more I think about it you may just have a bad driver. You tried several different combo's of amps and bi-amping and the problem seems to be constant. For whatever reason it sounds like you have a bad driver. Replace the driver and I bet you'll be fine. This is a farily rare occurance for Polk drivers, but these generation speakers aren't getting any younger.

Do you have other Polks with the same driver that you could swap out just to see?

H9

gyusher

Clipping will not over extend a woofer but it will create heat that will burn a VC. . . It might sound like hell but you need power to push it out that far. . .

Could be bad suspension letting the driver over extend. . .

dorokusai

The tapping may simply be a bad driver, as mentioned previously. I've found more than a few drivers in old Polk, that when driven to high volume, show their age. I haven't clipped a speaker in years.

heiney9

gyusher wrote:

Clipping will not over extend a woofer but it will create heat that will burn a VC. . . It might sound like hell but you need power to push it out that far. . .

Could be bad suspension letting the driver over extend. . .

Agreed, but in all situations in my experience when drivers popped it was because of lack of power not too much power. Regardless, I think his driver is just plain worn out for whatever reason. The VC is shot and causing the popping sound. I've sold many many orignal SDA's back when new and we could play them at very high volume with proper amplification and they never gave a hint of trouble. It was when people under powered them or used a loudness switch at moderate volume that they would pop, because of lack of power.

Joe, can you push on the bad driver and do you hear any scraping sounds? If so, the driver needs replacing.

Gyusher, not trying to be arguementative just relating my experiences and I've never heard of a quality speaker that has been over driven with too much power. It just doesn't happen very often. And the fact that Joe is having problems with all 3 amps and configurations leads me to believe the driver is old and failed or at some point he burned the VC by overdriving his amp, hence clipping it because of lack of power.

H9

BobMcG

I think it's probably a combination of a couple of things.

1) Maybe age to a small extent:
When my first pair of 2Bs (bought new in '88) got to be around 7-8yrs old I had to replace a couple of drivers in them because of this problem. (Not both at the same exact time.) Before this they always took everything put to them.

PLUS:

2) Over driven or bottomed out:
The speakers were being driven by a quality amp with plenty of oomph (260watts RMS at 8ohms and stable into 2ohm loads.)) and dynamic headroom (2dB) and no processors in the signal path. Listening at rather high levels was (and still is) the order of the day. A certain CD I'd play though had this one very strong bass point in it that would make a driver pop. After a couple of times of doing this the driver got worse and worse. Eventually the speaker started making scratchy noises and I found the spider to be ripped. Another driver ended up in the same shape not to far down the road and was replaced. I talked to Polk about this back then and if I'm not mistaken I think it was determind that the drivers were being over extended ripping the spiders. (You could still get exact replacements from Polk at that time.)

reeltrouble1

Is only one driver popping? If more than one then your amp is likely clipping, all amps will clip the wave when overdriven. When you reduce the gain does it go away for good?

I have had my 1C and SRS well over 100db spl without problems, but since I like want to hear things for my remaining days I rarely hit levels close to those.

RT1

Zen Dragon

Another possibility is the recording you are listening to itself. I know earlier in the thread someone requested details to include what you are listening to. I also like to play the speakers hard from time to time. Just love that enveloped in wall of sound thing. Anyway some music, modern rock especially is recorded at insanely high levels. I'll be listening to some Steely Dan at 11:00 on the volume dial, then put on Days of the New and it sounds like the speakers are going to exolde with audible distortion.
modern rock seems to frequently record the music at too hot a level. I guess the kids like it reeeeaaal loud, and it keeps a steady stream of teenagers in need of new speakers as they blow them.

F1nut

Lots of good suggestions/ideas. One thing for sure, it's not normal.

George, just a little integrated.

SDA SRS 1.2

Occasionally with my former TFM-45 I could drive the SDA's to unbearable levels and it would seem as if it had used up its "headroom" and sound harsh. With the Sunfire the SDA's seem to love the extra power but my ears can't take it! Just loud, clean sound!

joeparaski

Ok, I finally got a chance to do some checking this afternoon because I had the day off work (family breakfast at a sugar shack).

I went through all my connections and found a few rca connecters reversed. Much of the old SAE stuff is labeled Channel A for left and Channel B for right...a few were mixed up. That in itself is not a big deal but I got all those cleared up. I still got the popping and I tend to lean towards a couple of bad drivers (it's hard to pinpoint exactly which one (or ones) btw.

The music I was listening to is Madonna's latest cd cuz I wanted to "kick ****".

Now as you know I had the 2.3tl's sitting in the corner unused. What the heck, I set those up beside the SRS speakers and tucked the dual SVS subs behind each one. The SAE pre-amp has 2 main outs, one went to the SAE electronic crossover (crossover frequencies set as per the Polk manual) where the Phase Linear 350 wpc fed the bass and the Phase Linear 200 wpc fed the highs. The second pre out sent the signal to an SAE 300 wpc which fed the 2.3tl's. The Carver sound processor went through a tape loop on the pre-amp and it sent a signal to the Samson 500 wpc to power the dual SVS subs and the center channel signal went to the SAE 100 wpc to feed the CSi5 (removed the connector on the binding post and sent the left channel to one input and the right channel to the other input on the csi5). Note...ran out of speaker cable and missing one amp to drive the rear FXi5's.

Nervously turn everything on and there is NO smoke coming out of anything (always a good sign). Hit PLAY on the Madonna cd and slowly bring up the volume.....hmmmmm....it's playing...ALRIGHT!! Start cranking some volume and the VU meters are starting to show some activity.....no popping.....add some more volume......no popping.....add some more.....man this thing is getting loud and still sounding clean.......add even more.....now the freakin walls seem to be shaking and the bass is just awesome and I feel my breakfast moving in my stomach....I get a sensation like I'm standing next to a Nitro funny car warming up in the pits at the Summernationals. No popping, just loud and clean (at least to my ears). Now I'm all smiles and sit down on the couch to take it all in. Now THIS is what I was looking for!! Ok, this may not be a true "audiophile" sound, and a purist may think it's crap, but for me, it sounds good. I'll listen to some jazz and classical next and see how it sounds.

I've got a new SPL meter and I'll take a reading to see what I've got. I still have to go through all the fine tuning and adjustments with the AVIA DVD at some point, but I'll wait till everything is hooked up, plus I still don't have a dvd player to use in this system.

I bought a DAC from a member which hasn't arrived yet so I imagine that it will improve the sound from the Sony carrousel cdp. This is getting exciting!! My dream system is finally coming together.

I want to thank you guys for your suggestions (keep them coming) and I'm always learning here on this forum.

heiney9

The music I was listening to is Madonna's latest cd cuz I wanted to "kick ****".

Well there's lots of bass energy in this recording and it's not natural, it's synthesized and really, to be honest, it's a pretty horrible recording. Atleast compared to what I like. I'm listening to it as I type. Really it's not the most stellar recording (very compressed and a very hot mix ) or style of music to make the SDA's shine. I could see how listening to this cd at high levels could do some damage. Not knocking you choice of music it's just a fact.

Sounds like since the 2.3tls aren't giving you trouble; the SRS's just have a bad driver or two. Try pushing the cones in and see if you hear any scraping that might tell you which need replacing.

Keep rocking or dancing....but don't blow anything up :eek: .

H9

Dennis Gardner

I am assuming my issue was an old bad driver, since I was playing a particularly driving bass guitar track from Brian Bromberg - Choices when I lost my mid driver. I have since replaced it and have been afraid to play it that loud again.

My setup when I had the issue was my Pioneer DV45A universal, Audio Experience tube preamp (no tone or balance controls on it) and Odyssey Stratos amplifier. I was running at what I would say was 90% of full power as I have clipped the Odyssey before and notice how smoothly it clips and loses dynamics, simply a slight compression of the music. This driver destroying track was totally different than the clipping I had heard before. I do know that when you clip an amp it can create a very low sub harmonic that can damage drivers also, but since the mids don't really dig that deep and the bass is a function of the PR, I would think the mids of this Polk design are not affected by this harmonic. I could be clearly wrong in my understanding, though. What I do know is that I can't find enough original 6511s to fill my boxes so I will be careful how I listen.

reeltrouble1

Joe,

If the SRS have blown drivers there is a reason. Think about it and the reasons why.

RT1

joeparaski

Heiny....any suggestions as to which cd I should listen to to make the Polks "shine"?

I just went and pushed the cones.....if I push evenly on both sides, there is no sound. If I push on one side only, there is a scraping sound on ALL of them (I would think that it is normal when pushing on one side only).

I took some pictures and I'll post them (as soon as I figure out the best way to do so).