Dynamic Headroom question...

heiney9

cnh wrote: »

Interesting, info above...so I guess I've been operating on false numbers, as I'd read/misread somewhere that to double the loudness you needed to 10 X the wattage so that 1000 watts would be twice 100 watts. Which is why you see so many subs above the mid-range at 1000 watts or more? And class D-amps as the choice because of the gross need for power for BASS amping.

cnh

You need 4X the power to double the output.

The reason Class D amps are used for bass amps is because of size, effeciency, and lack of heat and inexpensive cost. Since bass is relatively impervious to the switching power supply's in typical class D amplification as well as notch distortion and all other gremlins associated with cheaper class D amplification aren't present at the output.

H9

polkie4life

Do you have to manually select the surround mode when you play a dvd?

What dvd player do you have? How is it connected to the processor?

cnh

Thanks Heiney9,

That's what I thought...also we should take a moment in this post to remember Max Headroom. Do you guys remember that floating Video-head?

cnh

heiney9

cnh wrote: »

Thanks Heiney9,

That's what I thought...also we should take a moment in this post to remember Max Headroom. Do you guys remember that floating Video-head?

cnh

That song is on an Art Of Noise Cd and it's a fantastic SDA demo piece......so yes I do remember it and listen to it occasionally.

MillerLiteScott

Your system's dynamics should scare you or take you by surprise IMHO. My system still takes me by surprise even with movies I have watch several times and know what is coming.

That is my take on this subject.

heiney9

MillerLiteScott wrote: »

Your system's dynamics should scare you or take you by surprise IMHO. My system still takes me by surprise even with movies I have watch several times and know what is coming.

That is my take on this subject.

Ed Zachary!!!

cokewithvanilla

MillerLiteScott wrote: »

Your system's dynamics should scare you or take you by surprise IMHO. My system still takes me by surprise even with movies I have watch several times and know what is coming.

That is my take on this subject.

mine too.

so wheres my scare? :P

anyhow, I have some panasonic dvd player, nothing fancy. I can't find the remote at the moment, so that doesn't help. Do cheap dvd players even have dynanics settings? besides, its connected digital, so isnt the preamp doing all the work?

treitz3

cokewithvanilla wrote: »

anyhow, I have some panasonic dvd player, nothing fancy. I can't find the remote at the moment, so that doesn't help. Do cheap dvd players even have dynanics settings?

Yes. Yes they do. That may be where your issue is stemming from.

cokewithvanilla

I found the remote. The dynamic range setting was set to "off". this means that it does not compress anything. Bitstream or PCM are the only other settings

treitz3

Damn. Unfortunately, I am unfamiliar with bitstream/PCM stuff as I'm a 2 channel guy. Maybe someone else can address that one bro'.

tcrossma

Yeah, I'm not sure what to tell you either. Unless there's something wrong with them, I don't think it's your speakers. I've never heard the 25's, but my 15's are more than adequate in that department and I'm sure the 25's are similar. I also wouldn't think it's the amp.

So myself I'd be pointing fingers first at a setting in the processor or DVD, and then maybe either the source material itself, a not-so-good DVD player, and then maybe the processor. Good luck with it, hope you get it figured out.

lightman1

An analogy. Dynamic headroom is to an amp as a nitrous bottle is to a motor. It's there if you need it, but can detonate a motor(amp) if you use it to much.
That's why short term capacitance and some slew rate specs are important. FWIW

polkie4life

cokewithvanilla wrote: »

I found the remote. The dynamic range setting was set to "off". this means that it does not compress anything. Bitstream or PCM are the only other settings

I'm not sure either, i thought those choices only pertained to blu ray? You could try both i guess and see what happens...

When you play a dvd what surround format shows up on the processor?

cokewithvanilla

hmm. I mean, I just swapped amps, and I'm listening to The Eagles: Hell Freezes Over right now, and on both amps it sounds wonderful. However, I put in V for Vendetta, and when he blows up that first building, it just wasn't there.

cokewithvanilla

polkie4life wrote: »

When you play a dvd what surround format shows up on the processor?

Whatever the movie is... DD or DTS... but since i'm running 2 channel right now its DD 2.0/2.0 dunno what it would say for dts,, maybe DTS 5.1/2.0... I can check.

I wish I had a dvd or cd that I knew how it sounds elsewhere so that I can be sure that it isn't just my ears.

polkie4life

I'm lost here...

PCM i think is analog (via rca's), Bitstream is digital (via coax/opt) and this is what you want, the processor doing the decoding. If the processor automatically goes to DD/DTS it'll be receiving bitstream. The problem must lie with the processor if this is what is happening.

Good luck and hope you get it sorted.

heiney9

treitz3 wrote: »

Damn. Unfortunately, I am unfamiliar with bitstream/PCM stuff as I'm a 2 channel guy. Maybe someone else can address that one bro'.

Bitstream and PCM are for 2ch use, not DTS or the other DD settings for 5.1 or 7.1. Perhaps that's the issue. Especially if the movie you are watching is optimized and mixed for best results using the DTS setting.

H9

cokewithvanilla

It's weird because the dvd player has a menu for DTS and a menu for DD... it's like this

Audio Settings>
DD>
Bitstream
PCM
DTS>
Bitstream
PCM

McLoki

How is your DVD player connected to your reciever? optical, coax, hdmi, standard right left cable?

it is almost sounding like it is not hooked up correctly and you may be running pro-logic rather than DTS or DD.

tcrossma

For both of the DD and DTS items, select "Bitstream" so that the un-encoded signal gets sent to the processor. Then on the processor make sure that one of your DD or DTS modes are selected -- make sure it's not a simulated mode such as Pro-Logic. From your prior posts it kind of sounds like you already had this part of things setup correctly though, so I'm not sure this will fix anything for you.

cokewithvanilla

The default settings are Bitstream on both. As the manual says,

Select “BITSTREAM” when the equipment
can decode the bitstream (digital form of
multi-channel data). Otherwise, select “PCM”.


I should go get a DTS movie with good dynamics. Is batman in DTS?

Also, I play all my music from my computer... I'm going to see if I have some DVD software laying around so I can try a dvd on there.

EDIT: I tried my computer, it showed as Digital 48K, Dolby Digital 5.1/2.0

I supposed 5.1/2.0 means converting 5.1 to 2.0? could this be a problem?

heiney9

If you are only using 2 channels (ie; the 2 front speakers) you'll never get the experience you're looking for.

You haven't made it real clear if you are running more than the just the LSi's.

cokewithvanilla

I am using two channel. I just turned on center, surround and sub in my processor. NOw when I play the movie, of course, I hear no voices. However, during the explosion scene I don't hear 90% of the explosions, only the background music. It seems like the center would be doing all this work. Could this be the problem? the sound was not even intended for the front speakers?

tcrossma

cokewithvanilla wrote: »

I am using two channel. I just turned on center, surround and sub in my processor. NOw when I play the movie, of course, I hear no voices. However, during the explosion scene I don't hear 90% of the explosions, only the background music. It seems like the center would be doing all this work. Could this be the problem? the sound was not even intended for the front speakers?

That shouldn't be a problem in and of itself, no. I am currently running a 2.0 system with my LSi15's (because I care more for 2-channel than HT) and movies / TV have dynamics galore.

heiney9

cokewithvanilla wrote: »

I am using two channel. I just turned on center, surround and sub in my processor. NOw when I play the movie, of course, I hear no voices. However, during the explosion scene I don't hear 90% of the explosions, only the background music. It seems like the center would be doing all this work. Could this be the problem? the sound was not even intended for the front speakers?

Well, you can't run DD or DTS which is where most of the dynamics are processed. I use 2ch with my SDA's for movies and do have a great experience but compare that to my brothers more inexpensive TSi 5.1 HT with sub and there is no comparison as far as action sounds, deep rumble and overall dynamic experience.

If you are running 2 channel the setting needs to be set to PCM and even then some discs don't have a decent 2.0 track because not a lot of people use that for HT.

Your issue is lack of the other 3.1 channels as well as having the incorrect settings on your DVDp or processor. Setting it for 5.1 when you only are have 2 channels never sounds good..............to many holes in the processing. In fact if you are only running a L/R you can't even hear DTS.

You can set the processing to 2 channel PCM and still have dynamics and nice movie experience, but not like 5.1 and you are still at the mercy of the disc. If they didn't mix a decent 2.0 track then it will be lacking. I have several music DVD's that are 5.1 DD only. They still sound OK, but not as good as if they had a 2.0 PCM track. (remeber I'm only running 2 channels, no processor)

H9

tcrossma

heiney9 wrote: »

Well, you can't run DD or DTS which is where most of the dynamics are processed. I use 2ch with my SDA's for movies and do have a great experience but compare that to my brothers more inexpensive TSi 5.1 HT with sub and there is no comparison as far as action sounds, deep rumble and overall dynamic experience.

If you are running 2 channel the setting needs to be set to PCM and even then some discs don't have a decent 2.0 track because not a lot of people use that for HT.

Your issue is lack of the other 3.1 channels as well as having the incorrect settings on your DVDp or processor. Setting it for 5.1 when you only are have 2 channels never sounds good..............to many holes in the processing. In fact if you are only running a L/R you can't even hear DTS.

You can set the processing to 2 channel PCM and still have dynamics and nice movie experience, but not like 5.1 and you are still at the mercy of the disc. If they didn't mix a decent 2.0 track then it will be lacking. I have several music DVD's that are 5.1 DD only. They still sound OK, but not as good as if they had a 2.0 PCM track. (remeber I'm only running 2 channels, no processor)

H9

I don't think this is accurate. My receiver can process DD or DTS and if the speaker selection is OFF for the center or rears it routes those signals appropriately to the fronts.

heiney9

tcrossma wrote: »

I don't think this is accurate. My receiver can process DD or DTS and if the speaker selection is OFF for the center or rears it routes those signals appropriately to the fronts.

OK, let me explain further, I use a high end 2 channel preamp. If I set the audio settings on the DVDp to DTS I get no sound at all. If I set it to 5.1 DD I get a bunch of ambient sounds with lack of a center and other information missing. If I set the DVDp audio section to 2.0 PCM I get a full 2 channel signal; if the disc is recorded in 2.0 DD sometimes (because of lack of a 2ch PCM track) I get some weird effects. Still totally listenable.......just lacks some things like center focus for vocals/dialog, etc.

H9

TNRabbit

Back to square one. Are you near another Polkie who can offer advice or you can compare systems?

tcrossma

heiney9 wrote: »

OK, let me explain further, I use a high end 2 channel preamp. If I set the audio settings on the DVDp to DTS I get no sound at all. If I set it to 5.1 DD I get a bunch of ambient sounds with lack of a center and other information missing. If I set the DVDp audio section to 2.0 PCM I get a full 2 channel signal; if the disc is recorded in 2.0 DD sometimes (because of lack of a 2ch PCM track) I get some weird effects. Still totally listenable.......just lacks some things like center focus for vocals/dialog, etc.

H9

Ok right, but that's because you're using a 2-channel preamp and not a processor/receiver like the OP is. So it's really not an apples to apples thing I don't think. He should be able to set the DVD and receiver up as DD/DTS and just turn off in the processor the speakers he's not using and be A-OK.

cokewithvanilla

Well, for example, V for Vendetta doesn't have a 2.0 track. I checked the disc, it isn't there. It only has DD 5.1.

This is how my preamp does things.... if it has a 5.1 track, and it sees that I have a different number of speakers (2.1,3.1,7.1,9.1,9.3) then it will process the track and put everything to the speakers that I do have.

So, in DD or DTS I can listen to a 5 channel track with only two channels, without holes (at least without any I can hear, I most certainly get all the center channel information)

I tried to listen to the difference in the 2.0 and 5.1 tracks on Star Wars Ep. 3, and the 5.1 sounds better, even though my preamp is processing it to 2 channels.

Oh, and by the way, there is no change in dynamics from the 2.0 and 5.1 track.... though the 5.1 sounds much better.