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davef
01-06-2004, 12:08 PM
Hi trekkerj!

Could you better describe what you are specifically hearing? I will try to help..

When you say vibrations, would this be closer to:

1. A crackly or static sound like crumbling tinfoil in your hand?
2. A specific rattling sound like something loose is vibrating against something else.

Is this sound volume dependant? Is It heard at all volume levels or at just loud volumes?

What reciever are you using? What television?

Thanks for your time.


Good Sound To You!

David Fabrikant
www.ascendacoustics.com

trekkerj
01-06-2004, 12:19 PM
OK, it's difficult to describe. It definitely is volume dependent. I have dynamic range control on my receiver OFF. High volume, high frequency audio seems to produce this distortion I'm hearing. It's like the volume is too high (but it's not). If I heard the same thing in a .wav file, I could use a low-pass filter or normalize the volume. Shouldn't this speaker be able to handle these things better?
I have a Pioneer VXS-D509S receiver with a Toshiba 57HDX82 TV.

davef
01-06-2004, 12:41 PM
Hi trekkerj,

I believe what you are experiencing is your receiver "clipping". This is caused when too much power is being demanded from your receiver's amplifier, more than it is able to supply. This will cause the normally rounded sine waves of the signal to be clipped and look more like square waves. The result is a high level of distortion which typically sounds like crackling and is extremely volume dependant. Again, this is being produced by your reciever, not the speaker, which is why you have heard it with two completely different speakers.

The reason you hear it out of the center channel is that for a movie soundtrack, at least 70% of all sound is directed towards the center.

Our 340 center is capable of handling a tremendous amount of power, however, it is simply reproducing the signal it is being fed.

I would suggest that you upgrade your receiver, or, if your receiver has center pre-amp outputs, add an additional amplifier just for the center channel usage. This has many additional advantages as well.

It is also very possible that your receiver could have something wrong.

Hope this helps!




Good Sound To You!

David Fabrikant
www.ascendacoustics.com

trekkerj
01-06-2004, 12:45 PM
Great, just what I needed to hear. :)

Do you have any recommendations for any receivers or amps? Is there any way to test this theory before spending additional money?

Are there any specs for my receiver that you could look at and see if it might be an issue?

BTW, i say it's volume dependent, but I'm still not really 'blasting' the volume very high. I don't know if it's clipping, it sounds more like a vibration.

davef
01-06-2004, 12:58 PM
Hi trekkerj,

I have already checked specifications on your receiver and this did help confirm my conclusions.

There is no simple way for you to 100% confirm this. First off, what speakers are you using for your left / rights? You could try placing one of your left/right speakers in place of the center and turn up the volume of the center so that it matches the same volume level when you heard the distortion from the 340 center. If you still hear the distortion, absolutely a receiver issue...

We now sell H/K receivers which are well know for the high current capability their amplifiers can provide. These have considerable headroom which is what you need. Give us a call or send me an email and I would be happy to offer you a great price on a unit.


Good Sound To You!

David Fabrikant
www.ascendacoustics.com

trekkerj
01-06-2004, 01:05 PM
So what about my receiver helped you reach your conclusion? I want to understand this more.

Currently, I still have the cheapo Jensen speakers as left/rights. I ordered 4 CBM-170s to replace those.

Also, turning up the volume to a certain level doesn't product distortions all the time. The is usually during certain vocal sounds that causes a small vibration off of something.

azanon
01-11-2004, 09:08 PM
I've noticed a little crackly sound out of my left front 170 when i really turn the volume up to "45" on my sony receiver, trekkerj. When i push it past "55", they all start sounding like mush. I dont have a decibel meter with me, but "45" is pretty loud - not uncomfortable loud, but i wouldnt want to listen at that volume for 4 hours every day as to probably have long term hearing loss. Thing is i have a 200 dollar sony receiver. I'm pretty sure its the culprit, because at, say, "30", all 5 speakers sound like a dream.

Bradley

BradJudy
01-11-2004, 10:07 PM
Bradley,

Be careful - it sounds like your amp is clipping at high levels and clipping can damage speakers. Either keep the volume down or get a new receiver.

Brad

trekkerj
01-11-2004, 10:08 PM
The crackling doesn't happen at very loud volume levels. However, my Pioneer is infamous for needing loud volume readings. A good volume level for me is -35db. I think the crackling is at the source, but I'm not 100% sure. However, my new 340c center doesn't impress me (or at least, it doesn't sound like a $200 improvement). At least not yet. I am still running my 4 front/surrounds from my cheap Jensen set. So I am reserving judgement for when I get the 4 170's and calibrate the speakers. Hopefully that will make it all come together. For now, the center sounds like it has more bass response, but I can simulate that on my old center by turning up the sub volume.

<blockquote id="quote"><font size="1" face="Arial, Verdana, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">Originally posted by azanon

I've noticed a little crackly sound out of my left front 170 when i really turn the volume up to "45" on my sony receiver, trekkerj. When i push it past "55", they all start sounding like mush. I dont have a decibel meter with me, but "45" is pretty loud - not uncomfortable loud, but i wouldnt want to listen at that volume for 4 hours every day as to probably have long term hearing loss. Thing is i have a 200 dollar sony receiver. I'm pretty sure its the culprit, because at, say, "30", all 5 speakers sound like a dream.

Bradley
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">

azanon
01-11-2004, 10:24 PM
Brad,

Oh i didnt know that. I was trying to tear up the Sony so my wife would go for me needing a new receiver. Dont want to ruin the Ascends in the process!

Bradley

Quinn
01-12-2004, 12:22 AM
Trekkerj- Can you borrow a receiver from someone? It may be easier to take the CC and material you know causes what you are experiencing to someone house and see what happens.

My other thought is where do you have the CC? Is it possible that certain frequencies vibrate what it is sitting on? Try moving it or putting something that dampens under it and see what happens.

trekkerj
01-12-2004, 12:30 AM
I already put the speaker on the floor, still happened. It was a particular DVD. I played in on my computer and it did the same thing. I also hear it when watching TV occasionally, but I guess it could also be bad audio levels at the source. Doesn't anyone else get this type of clipping when watching tv on occasion?

<blockquote id="quote"><font size="1" face="Arial, Verdana, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">Originally posted by Quinn

Trekkerj- Can you borrow a receiver from someone? It may be easier to take the CC and material you know causes what you are experiencing to someone house and see what happens.

My other thought is where do you have the CC? Is it possible that certain frequencies vibrate what it is sitting on? Try moving it or putting something that dampens under it and see what happens.
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">

Quinn
01-12-2004, 01:16 AM
Your source is causing the same thing on your computer speakers?

trekkerj
01-12-2004, 01:53 AM
Yes. It is a "Friends" dvd. Happened on the computer speakers also. Not on my bedroom tv, but I guess those speakers aren't as sensitive to it.

I'm just concerned that during regular TV I get it sometimes. It is very subtle, but I noticed it during one of the football games, and also a basketball game on TNT when the announcers are talking.

<blockquote id="quote"><font size="1" face="Arial, Verdana, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">Originally posted by Quinn

Your source is causing the same thing on your computer speakers?
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">

JohnnyCasaba
01-12-2004, 02:12 AM
I have also heard the sound you are describing but only when watching football on the TV. I don't get this at any other time. Should also point out that it is not all the games, but just on some, and I usually use PL2 when watching the games. Just think it is a problem/limitation with the stereo TV broadcast. Have also noticed that the sound of the football games on ESPN, which I get in DD 2 channel, is much better and I never heard this sound on those broadcasts.

trekkerj
01-12-2004, 02:18 AM
Also, since I have digital cable, many of the channels are still analog, and it seems like each of them have a different volume level. I also notice the distortion on many of these channels at times.

Anyway, as for my previous question, like I said, I notice a difference with the new center channel, but only minimal. I have the other 4 speakers on the way. Can I expect to finally notice a huge improvement once my 4 older speakers are replaced with the Ascends? I am a little dissapointed so far. I am thinking either I was expecting too much, I need the full complement of speakers, I need to give them more time to break in, or I need a new receiver. Any thoughts?

<blockquote id="quote"><font size="1" face="Arial, Verdana, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">Originally posted by JohnnyCasaba

I have also heard the sound you are describing but only when watching football on the TV. I don't get this at any other time. Should also point out that it is not all the games, but just on some, and I usually use PL2 when watching the games. Just think it is a problem/limitation with the stereo TV broadcast. Have also noticed that the sound of the football games on ESPN, which I get in DD 2 channel, is much better and I never heard this sound on those broadcasts.
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">

JohnnyCasaba
01-12-2004, 03:26 AM
trekkerj,

We have had digital cable for a while, well before the surround sound setup, and noticed the volume level differences even with the sound coming thru the TV speakers. Do you have your cable box hooked up to your AVR with a digital connection or analog? I don't watch a lot of TV with the surround sound setup, mostly football (GO EAGLES!), 24, Survivor, Line of Fire, and the movies and shows on HBO. The only time I heard the sound you described was with a couple of the football broadcasts on Fox, NBC and ABC, which I get only in stereo. It was very annoying and I had to turn off the AVR to enjoy the game. In fact, I think there was a local game here that was being broadcast on both ABC and ESPN and I was getting the problem on ABC (stereo) and not on ESPN (DD 2 channel).

I do think once you get all the speakers setup and everything dialed in, it should sound better than your old Jensen setup. As for the new AVR, maybe once you get all the speakers and you are still having problems, get one from Best Buy or Circuit City to demo to see if it is better. Both stores have a very liberal return policy.