Speakers crackle during certain dialogue

[littleruss21]

ok i have a marantz sr5400 reciever with
2 DM602.5 Front Floorstanders
2 DM601 Rear Bookshelf
1 LCR600 Center Channel
1 ASW650 Subwoofer
All are Bowers & Wilkins, i have ammassed this system over a number of years so you imagine its importance to me.
The problem is during certain parts in movies mainly during dialogue with no soundtrack(Mothman Prophecies when they are in the bathroom with will patton pointing the shotgun at richard gere...also on the movie 21 grams when the preacher is yelling at the congregation and benicio del toro is apart of it) ok well during these parts there is some crackling at the end of thier speech on the last syllable...it only seems to be at certain pitchs because in other parts of the movie there will be dialogue with no music , and the volume will be loud, and there is no crackle...i have tried to tweek my amp but i am afraid i don't know what a lot of the stuff means...i am almost sure it isn't a blown speaker because it handles music cds and even music in movies just fine at very hi volumes now the center channel is on the lower shelf of my tv stand but i mean it has rubber grommets between it and the glass...so i guess i need to know what to try and remedy this...if you need more info just ask i really just appreciate the help


thank,
andrew

 

[einsteinjb]

Nobody replied yet? And your very first post no less? How rude.

OK well I'll try to help you a bit. I'm familiar with the B&W DM600 series though you didn't say which Series you have, the original, S2 or S3. Doesn't matter for the purposes of troubleshooting, just wondering. I'm also not familiar with your Marantz receiver.

Now when you're watching these movies and this happens, exactly how loud is it? Hard to qualify I'm sure but are you watching LOUD? You may have something loose in your center tweeter. I would suggest first seeing if it happens at lower volumes. If not then it's not just a glitch in the soundtracks.

Then you might try swapping the center for another speaker and listening closely to see if it does it on that speaker as well. Have you determined it's definitely coming from your center? If not you'll need to go put your ear close to the center to make sure it's coming from that speaker and that one only.

Here's a remedial question: you don't happen to have the center channel volume cranked up in the receiver's setup menus do you? If you do you might be overdriving that channel.

You really just need to use basic troubleshooting methods like this to track down exactly when and where it's happening, under what circumstances. listen closely to each speaker til you know where it's coming from, or disconnect speakers til you locate it, etc. If you try all this and you become certain it's the center channel's tweeter physically doing something, you should probably take it to your B&W dealer to have it looked at. I don't think getting a 600 series center tweeter repaired would cost a fortune. It's always possible you have a very slight tear or something like that in the tweeter that's not preventing it from working most of the time or at lower volumes but that does cause it to spit at you in especially challenging moments.

Hope this helps.

 

[hifiman]

I've had this problem since the days of those new-fangled HI-FI VHS VCRs. Often times the recording level on movies is too high and I would get a crackling sound from one speaker or another. Since making the switch to DVD it happens infrequently, but I do get a crackling from time-to-time. I too have never had the crackling from other sources.

 

[tbewick]

I've heard some fuzziness in the speech with Dolby Digital soundtracks at high volumes. It's possible that you are hearing the effect of AC-3 compression. I've found applying a treble roll-off/cinema eq helps to reduce the audibility of this fuzziness. In this post I've included the eq curves of the THX re-equaliser (on the left) and the Denon cinema equaliser (on the right) [Source: Home Cinema Choice]. The quality of Dolby Digital playback will vary with the quality of the Dolby Digital decoder. Maybe on more expensive receivers, such compression artifacts will not be audible. DTS tracks I've heard don't have this problem.

It is also possible that you are playing the receiver at too high a volume and that it is clipping. B&W speakers are known for their clarity, but they can be quite difficult for the receiver to drive at high volumes. In fact, B&W have been criticised for not testing their cheaper speakers on less powerful amps (they do their tests on 1 kW Krell monoblocks). Most people buying their cheaper speakers won't be using such a capable amplifier. B&W also use their own standard when deciding what impedance their speaker is. Their newer speakers rated at 8 ohms can dip all the way down to almost 3 ohms, making them more demanding on the amplifier.

It could also be that you are hearing faults on the original soundtrack.

 

[MACCA350]

tbewick wrote:

It could also be that you are hearing faults on the original soundtrack.

Unless littleruss21 is pushing his equipment to clipping levels, then this is the most likely answer. Check this by playing the same scene at low volumes, if its still there then it is most likely in the recording.

I have heard this crackling in a some movie tracks played at any volume and, from memory, its almost always in the dialog, and mostly when someone is yelling/shouting. I believe this artifact is made in the recording studio when they do the voice recording. When the recording is taken, you can imagine the person is yelling or screaming into the Mic at only a couple inches away, this then will be mixed into the track at any volume level, so you could have a loud recorded voice playing at a softer level to match onscrene action in the final mix.

How loud can their Mic's record before adding distortion products? I don't know, but a person can yell over 130db at a couple of inches. I don't know how much above 130db cause thats the limit of my SPL meter and my Miss's topped that without even blinking

So if you hear this at low volume, and unless you've blown your tweeters, there is not much you can do about it. As tbewick said, Cinema EQ may help

cheers

 

[einsteinjb]

tbewick wrote:

Unless littleruss21 is pushing his equipment to clipping levels, then this is the most likely answer. Check this by playing the same scene at low volumes, if its still there then it is most likely in the recording.

I have heard this crackling in a some movie tracks played at any volume and, from memory, its almost always in the dialog, and mostly when someone is yelling/shouting. I believe this artifact is made in the recording studio when they do the voice recording. When the recording is taken, you can imagine the person is yelling or screaming into the Mic at only a couple inches away, this then will be mixed into the track at any volume level, so you could have a loud recorded voice playing at a softer level to match onscrene action in the final mix.

How loud can their Mic's record before adding distortion products? I don't know, but a person can yell over 130db at a couple of inches. I don't know how much above 130db cause thats the limit of my SPL meter and my Miss's topped that without even blinking

So if you hear this at low volume, and unless you've blown your tweeters, there is not much you can do about it. As tbewick said, Cinema EQ may help

cheers

I would hope that any legitimate movie studio producing big budget movies would be using sound engineers good enough to know how to set their input gains and other settings for whatever mic they're using in a given recording situation... I would HOPE. Such of course is not always the case in the real world. And even good engineers make mistakes, like not realizing how loud a particular actor or actress might get while doing a particularly energetic scene and not being prepared for it. It's always possible that there was clipping in the signal path somewhere, and maybe the engineer pointed it out or maybe not, but maybe the director said I don't care, that was the take I wanted, we're not doing it again (Can't you fix it in the mix? )

Point is things happen and it's definitely possible that the noise you're hearing is in fact on the source. Try the suggestions we've made like listening at a lower level or switching speakers or even checking it out on someone else's system and it should be fairly easy to track down where the problem is occurring.

 

[Lee Batchelor]

Hey Andrew!

I have a rather large home theatre, in fact, it isn't really a home theatre, it is a real theatre system suited for about 200 people. I do get center channel distortion on occassion and I would say it is over-modulation on the part of the mixdown engineer. I say this because I can put another source in and play it through the same sound field on the amp and there is no distortion. If the engineers messed up the final mix-down, you're stuck with it. If all your programs sound this way, then there is a problem elsewhere.

Hope this helps..........Lee

 

[kellyk75]

Andrew,

Did you ever find the solution to your problem? I am experiencing something similar but on not as nice a system.

 

[madhulsinghal]

I am having similar problem during dialogues in my Audiosolutions Overture centre speaker. Previously I had YAMAHA RX-V 683.

Now I upgraded to Yamaha Rx-A 3080. But that did not solve the problem of high pitch crackling and squeaking sound during dialogues (especially when there is no background music).

If it's clipping, can my speaker be saved? Can this problem be solved?

 

[everettT]

I am having similar problem during dialogues in my Audiosolutions Overture centre speaker. Previously I had YAMAHA RX-V 683.

Now I upgraded to Yamaha Rx-A 3080. But that did not solve the problem of high pitch crackling and squeaking sound during dialogues (especially when there is no background music).

If it's clipping, can my speaker be saved? Can this problem be solved?

What is the source? Is it all sources? Blown tweeters can do it as well as a poor source material, ie rips

 

[TLS Guy]

I am having similar problem during dialogues in my Audiosolutions Overture centre speaker. Previously I had YAMAHA RX-V 683.

Now I upgraded to Yamaha Rx-A 3080. But that did not solve the problem of high pitch crackling and squeaking sound during dialogues (especially when there is no background music).

If it's clipping, can my speaker be saved? Can this problem be solved?

I have not heard of Audio solutions speakers before. I have been on their website. Information is somewhat sparse, but their speakers are very low impedance. That center of yours is 3.5 ohms. Their tower speakers are 4 ohm with a minimum impedance of 3.25 ohms. The frequency at which this occurs is not stated.
However their is enough information there to make me think it is very unlikely those speakers can be used with any current receiver.

Now receivers, which I have never liked, are now getting worse. There are just too many amplifiers under the hood now.

I downloaded the user manual for your receiver. Only specs are given for 8 ohm loads. There are now hardly any speakers except the odd cheap bookshelf speakers that are truly 8 ohms, even if they claim to be. There are no specs given to 6 ohms let alone 4.

Now I don't know what your other speakers are. However the manual follows what I regard as a disturbing trend. It states this receiver, which is at the upper end of the market has to be moved to the 6 ohm setting (which by the way will limit unclipped output) to run any 4 ohm speaker. It also says that if the receiver is set to 6 ohms then four ohm speakers can be used on the front right and left channels, but then the other speakers must be 8 ohm.

To me this receiver seems only fit for purpose if external amps are used. I have a feeling that this is the reason for your problem. Further if you persist with this then I suspect that receiver will have a very short life.

What I would do is disconnect all your speakers, and just connect that center to either the right or left front output. Set the impedance setting to 6 ohms.

Now play the speakers and see if you have crackling. If you don't you have your answer, If it does see if you can test it on a more robust four ohm capable amplifier.

I really do need to know the other speakers. I'm pretty sure that center at least is not compatible with that receiver or any current one.

Your solution is probably going to be very robust external amplification, especially if your other speakers are from the same manufacturer.

Another issue is that when sourcing speakers from a little known boutique brand like that, you can not assume that the speakers are competently designed. They often are not. Those unusually low impedance values, are to me a red flag that the designs may well not be competent.

 

[AcuDefTechGuy]

I am having similar problem during dialogues in my Audiosolutions Overture centre speaker. Previously I had YAMAHA RX-V 683.

Now I upgraded to Yamaha Rx-A 3080. But that did not solve the problem of high pitch crackling and squeaking sound during dialogues (especially when there is no background music).

If it's clipping, can my speaker be saved? Can this problem be solved?

This reminds me of my little NHT SuperZero speakers. They sounded great for regular CD music. But for movie dialogue, they would make that crackle sound during some dynamic high volume frequencies.

I have absolutely no such problem with more dynamic speakers.

 

[JerryLove]

Check the basics too. Make sure you don't have, for example, a whisker short.

That symptom would fit one.

 

[GrimSurfer]

Check the basics too. Make sure you don't have, for example, a whisker short.

That symptom would fit one.

That's a very good point.

As good electrical practice, it's wise to "tin" the speaker wires at both ends... or if using a crimped connector, adding a bit of heat shrink tubing to bridge the shank of the connector and insulation of the wire.

You can use silver solder, which as better conductivity than lead/tin mixtures, along with a thin smear of dielectric silicone after.

 

[R.Elder]

I’m having a similar issue as well with the Yamaha 3080 AV receiver paired with a uni-fi UC5 center speaker. I put my old 90s Cerwin Vega center that’s served me well (has ferro fluid tweeter) in to see if this problem persist and it isn’t as bad but I can still hear it. I have a pioneer SC 79 that still works. I wanted to finally get on the Atmos boat but this dialogue problem is making me regret my choice of the flagship receiver from Yamaha. The UC5 needed +6 dB and my C.V. is a 4 ohm with great efficiency. I have to set it at -6db. My fronts and surrounds are Klipsch kf-28s. Atmos speakers are all full size speakers as well. I have a svs pb13 ultra and a Martin Logan dynamo 700 watt for low end. I recently bought a power conditioner (Panamax) to make sure it wasn’t an issue.

 

[GrimSurfer]

My guess is that the problem is related to the speakers. Both the Elacs and CVs are four ohm. Efficient or not, four ohm speakers can put considerable load on an amp not designed for it.

 

[R.Elder]

I’m going to set the receiver to 6 ohm and see if that helps. I’m looking to drop some money soon so maybe a amp is possible. One of the nice features on this receiver is it has a couple balanced outputs but just for the stereo channels I believe. Thanks for the reply and I’ll comment if the setting change improves the performance of the receiver. I didn’t have any of these issues with the pioneer sc79 but it’s a class D and the Yamaha has a-b amplifier.

 

[GrimSurfer]

The Pioneer brochure lists that AVR as being four ohm capable, which explains why you didn't encounter the same problem with it.

 

[R.Elder]

The Pioneer brochure lists that AVR as being four ohm capable, which explains why you didn't encounter the same problem with it.

That makes sense. Since the ohms are constantly changing it must dip below 4 when it tries to create the frequencies that are distorted. Changing it to 6 ohm and using my CV center it seems the issue is much improved. I’ll have to put the Elac back in and see if I can use it or not.

I’m fixing to drop 4-6k in my system. Would you update the center or pick up an amp?

 

[GrimSurfer]

That makes sense. Since the ohms are constantly changing it must dip below 4 when it tries to create the frequencies that are distorted. Changing it to 6 ohm and using my CV center it seems the issue is much improved. I’ll have to put the Elac back in and see if I can use it or not.

I’m fixing to drop 4-6k in my system. Would you update the center or pick up an amp?

Sound and Vision reports UC5s impedance reaches a minimum of 4.76 ohms at 463 Hz. It is a relatively insensitive 85bB/W/m, and you are driving it at +6 dB. This means that this speaker is demanding a lot of current... perhaps more than you AVR can comfortably deliver on that channel.

Conventional wisdom is that upgrading speakers makes the best financial sense, but 4-6k can buy you an AVR capable of driving any speaker so you could go either way.