Doing 5.1 Differently

AcuDefTechGuy

AcuDefTechGuy

Audioholic Jedi
Oooooh! Okay that makes sense. So theoretically, I could keep my Elite 94 and just add some preamps. I already have the Sunfire 5 channel. Hmmmm....

I mean it's sorda would be like "why are you doing all that" and there is a lot of duplication, but what the hell?
Exactly.

Heck, a lot of people think we're crazy for not buying a $400 PS3, right?

The key thing is to get preamps with HT Bypass loop.

Say you got an Elite Universal player that does BD, SACD, DVD-A, CD with aweseome DACs and internal decoders w/5.1 Analog output.

You hook the Elite Player's Fr L + R to the Preamp #1. The C + LFE goes to Preamp #2. The Sur L + R to Preamp #3. You are now set for a Purist 5.1 Movie/Music System.

You hook the Receiver's Pre-out Fr L + R to the Preamp #1 HT Bypass L + R Input. Hook the receiver's Pre-out C + LFE to Preamp #2 HT Bypass L +R. Hook the receiver's Pre-out Sur L + R to Preamp #3 HT Bypass L+R.

Of course, the 3 Preamps just connect to your 5Ch Sunfire Amp.

So basically, when you want to use the Elite Receiver, the Preamps are 100% Bypassed. It is as if they are never even there! Bypassed.

Then someone says, "Man, receivers are great, but nothing beats good old class-A analogs for 2.0 CD Music."

You could argue.

But you keep your cool and you say, "Ah, how about good old class-A analogs for not only 2.0 CD Music, but also class-A analogs for 5.1 Music and Movies!!!":D

or 7.1.:D
 
TLS Guy

TLS Guy

Audioholic Jedi
Can anyone convince me that B&W 800D, 801D, or 802D are the best?

I'm trying to be open minded here.:D

I just can't believe that $23,000 speakers can't do 20 Hz - 20 kHz +/- 2dB or something, you know?
Compromises again, my friend! Lets look at the options.

Take the 800D. Correctly the crossover form the woofers is 350 Hz. Passive crossovers lower than that are a very bad idea. So the woofers have to go to 700 Hz at least.

So what are our options to lower F3. Increase the mass of the driver. Then the driver won't go as high as we need, and we can't lower the crossover without producing a powered active speaker. Make the suspension more compliant, (increase Qms). Now we have to make the enclosure larger. That gets into WAF and expense and shipping.

Now the 800D has a an F3 around 30 Hz. It does not sound bass shy at all. The only thing I notice, as with all reflex enclosures tuned in those regions, I'm aware of the port kick in, but that's because I'm used to listening to TLS systems.

My system has a calculated F3 of 27 Hz with second rather than fourth order roll off. In room measurements actually reveal the F3 to be 20 Hz, probably because of room effects and the much broader support of the driver by the pipe with a good TL design. They give you a real thump in the chest with canon fire etc, and produce earthquake like effects on the floor between my theater and the garage. But then my speakers are huge and not commercially feasible. So I can make a different set of compromises.
 
itschris

itschris

Moderator
Okay... I know you're speaking English, but I have no idea what you just said. F3? I'm thinking F1 help on my keyboard.

I'm stil getting up to speed on the really technical stuff so if you and AccuDefTech can dumb it down just a bit that would really help me understand what you're talking about.
 
itschris

itschris

Moderator
Oh man! I'm starting to get that giddy feeling... the kind you get when you start to seriously envision something you know you shouldn't even be considering.

This is becoming very doable... granted it's not Mcintosh monoblocks, but it's a step into a really cool direction.

What kind of preamps do you think would fit the bill? Elite only makes this:
http://www.pioneerusa.com/PUSA/Products/HomeEntertainment/AV-Receivers/EliteAmplifiers/ci.A-35R.Kuro. Maybe I just ditch my Sunfire.

Exactly.

Heck, a lot of people think we're crazy for not buying a $400 PS3, right?

The key thing is to get preamps with HT Bypass loop.

Say you got an Elite Universal player that does BD, SACD, DVD-A, CD with aweseome DACs and internal decoders w/5.1 Analog output.

You hook the Elite Player's Fr L + R to the Preamp #1. The C + LFE goes to Preamp #2. The Sur L + R to Preamp #3. You are now set for a Purist 5.1 Movie/Music System.

You hook the Receiver's Pre-out Fr L + R to the Preamp #1 HT Bypass L + R Input. Hook the receiver's Pre-out C + LFE to Preamp #2 HT Bypass L +R. Hook the receiver's Pre-out Sur L + R to Preamp #3 HT Bypass L+R.

Of course, the 3 Preamps just connect to your 5Ch Sunfire Amp.

So basically, when you want to use the Elite Receiver, the Preamps are 100% Bypassed. It is as if they are never even there! Bypassed.

Then someone says, "Man, receivers are great, but nothing beats good old class-A analogs for 2.0 CD Music."

You could argue.

But you keep your cool and you say, "Ah, how about good old class-A analogs for not only 2.0 CD Music, but also class-A analogs for 5.1 Music and Movies!!!":D

or 7.1.:D
 
TLS Guy

TLS Guy

Audioholic Jedi
Okay... I know you're speaking English, but I have no idea what you just said. F3? I'm thinking F1 help on my keyboard.

I'm stil getting up to speed on the really technical stuff so if you and AccuDefTech can dumb it down just a bit that would really help me understand what you're talking about.
Every speaker has a low frequency where it starts to roll off. The F3 point is the frequency at which the speaker is 3db down below the average level. For sealed boxes they roll off at 12 db per octave (second order) below that and so do properly designed TLs. The usual ported Qb4 alignment rolls off at 24 db per octave (fourth order). I hope this helps. So a TL that has a 3db point at 30 Hz will be 15 db down at 1 Hz. A fourth order ported speaker will be 27db down at 15 Hz.
 
itschris

itschris

Moderator
I hope this helps.
Are you kidding me? HA! I have no idea what the hell you're talking about really. I mean I do a little bit, but I don't know how to put into context in a real world example.

You friggin' guys kill me!
 
AcuDefTechGuy

AcuDefTechGuy

Audioholic Jedi
Are you kidding me? HA! I have no idea what the hell you're talking about really. I mean I do a little bit, but I don't know how to put into context in a real world example.

You friggin' guys kill me!
***hee***hee:D

Yeah, TLS Guy goes way above my head too.

But I think the important thing is that the B&W 800D is @ -3dB @ 30 Hz on the SPL vs Freq graph.

So in other words, it's something like 30 Hz - 20 kHz +/-3dB.

On the other hand, the Revel Salon2 was measured by Tom Nousaine @ 2 meters in a 7,500 sq. ft. room to be 28 Hz - 20 kHz +/- 1dB. The anechoic response measured by Stereophile is 20 Hz - 20 kHz +/- 3dB, while the In-room response was 17 Hz - 20 kHz +/-3dB and 12 Hz - 20 kHz +/- 10dB. The important thing was that the OFF-axis response was very similar to the ON-axis response.

But PENG said that one reviewer was not very impressed at all with the Salon2.
 
AcuDefTechGuy

AcuDefTechGuy

Audioholic Jedi
Oh man! I'm starting to get that giddy feeling... the kind you get when you start to seriously envision something you know you shouldn't even be considering.

This is becoming very doable... granted it's not Mcintosh monoblocks, but it's a step into a really cool direction.

What kind of preamps do you think would fit the bill? Elite only makes this:
http://www.pioneerusa.com/PUSA/Products/HomeEntertainment/AV-Receivers/EliteAmplifiers/ci.A-35R.Kuro. Maybe I just ditch my Sunfire.
No, I'm afraid the Pioneer does not have the Home Theater Bypass mode, like this Emotiva preamp:

http://www.audioholics.com/reviews/processors/emotiva-rsp-1-pre-amplfier

I looked at the $500 Rotel preamp, but it does not have HT Bypass either.

So the key thing is to look for preamps with the HT Bypass Mode.

Even my Denon PMA2000IVRs don't have the HT Bypass.

The cheapest brand new preamp that has this HT Bypass feature will probably be the new Emotiva RSP-2, which will probably be $600.

But you could start saving up for 3 MAC preamps, right?:D
 
P

PENG

Audioholic Slumlord
But PENG said that one reviewer was not very impressed at all with the Salon2.
I hear you, but be patient. I promised to look for that review this weekend and read it again. May be I interpreted it wrong or remember wrong. If I can't find it then forget it.

Either way if you like the way it sounds, go for it. For me, I love the sound and the look of the 802D and they were only driven by a Bryston at the time. It might have done even better, had they been driven with Krell, McIntosh of Class'e but then may be not.

In terms of reviews on the 800 series, there is one on the 803D and was given top marks. Would you like to read it, or you won't go that low? I am sure they sound better than any DefTech but that's just my opinion.
 
TLS Guy

TLS Guy

Audioholic Jedi
***hee***hee:D

Yeah, TLS Guy goes way above my head too.

But I think the important thing is that the B&W 800D is @ -3dB @ 30 Hz on the SPL vs Freq graph.

So in other words, it's something like 30 Hz - 20 kHz +/-3dB.

On the other hand, the Revel Salon2 was measured by Tom Nousaine @ 2 meters in a 7,500 sq. ft. room to be 28 Hz - 20 kHz +/- 1dB. The anechoic response measured by Stereophile is 20 Hz - 20 kHz +/- 3dB, while the In-room response was 17 Hz - 20 kHz +/-3dB and 12 Hz - 20 kHz +/- 10dB. The important thing was that the OFF-axis response was very similar to the ON-axis response.

But PENG said that one reviewer was not very impressed at all with the Salon2.
The problem is you need much more specs than you guys usually quote. I looked in to those Revel's on another thread, and they have a ridiculous design concept. It is physically impossible for them to sound good.
 
TLS Guy

TLS Guy

Audioholic Jedi
Are you kidding me? HA! I have no idea what the hell you're talking about really. I mean I do a little bit, but I don't know how to put into context in a real world example.

You friggin' guys kill me!
It's pretty simple. All acoustic devices have an frequency roll off at the top and bottom end. Generally the F3 point is the lower roll off point were the speaker's output is 3db below the average output. Then there is a slope after that, that is dependent on the enclosure design parameters. I gave you the real world example to put in context.
 
AcuDefTechGuy

AcuDefTechGuy

Audioholic Jedi
Even my Denon PMA2000IVRs don't have the HT Bypass.
AcuDefTechGuy- could you shed any light on how you decode the Dolby bit stream from your cable or satellite box if indeed you do that?
I would not be able to decode DD or DTS from the cable or satellite box. I would only get Analog Stereo from the cable or satellite box.
:D Okay, I just wanted to correct myself here.

I forgot that my Denon PMA2000s do have a "HT Bypass".

It's the AUX-2 Input. But for "HT Bypass" I would have to flip the switch on the BACK from AUX-2 to AMP. Thus I would have Tape1, Tape2, CD, Phono, Tuner, Aux1 to be used as Preamp and the AUX2 would be for the HT Bypass.

So for Satellite, HD Cable, etc., I would have to use a HDMI receiver or processor with a 5.1 Pre-out and connect to my AUX2 inputs. Problem solved.:D
 
WmAx

WmAx

Audioholic Samurai
Could you please disect/interpret these measurements for me?

http://stereophile.com/floorloudspeakers/608revel/index5.html
Except for the cabinet resonance, it measures nearly textbook perfect for a monopolar speaker.

I think TLS is against the low crossover point (130Hz), which in a passive, is difficult and expensive to do correctly, and as such, usually is not done correctly. But here, the measurements verify that it was done correctly.

-Chris
 
AcuDefTechGuy

AcuDefTechGuy

Audioholic Jedi
Except for the cabinet resonance, it measures nearly textbook perfect for a monopolar speaker.

I think TLS is against the low crossover point (130Hz), which in a passive, is difficult and expensive to do correctly, and as such, usually is not done correctly. But here, the measurements verify that it was done correctly.

-Chris
So which one tells us the cabinet resonance?

Here is the B&W 802D:

http://stereophile.com/floorloudspeakers/1205bw/index4.html

How is the cabinet resonance of the 802D compared to the Revel Salon2?

On the 802D, I see that at 60 Hz (anechoic), there is a huge + 7dB on the frequency response. At 10 kHz (anechoic), there is a + 4dB.
 
WmAx

WmAx

Audioholic Samurai
So which one tells us the cabinet resonance?
The articles clearly specify which graphs are the cabinet resonance plots.


How is the cabinet resonance of the 802D compared to the Revel Salon2?
Well, the B&W has two cabinets (mid/treble module and bass module) seperated by a suspension/isolation system. There is no comparison - the mid module of the B&W would not even register on the test because it's vibration amplitude was so low - and no graph is included for it because of this. The bass module has what appears to be very low level vibration around 60Hz, which I would wager is likely something loose in the cabinet or some other cause, as the cabinet could not possible actually resonate at 60hz with it's construction.

On the 802D, I see that at 60 Hz (anechoic), there is a huge + 7dB on the frequency response. At 10 kHz (anechoic), there is a + 4dB.
It can be hard to truse the LF measurement in Stereophile, as the measurement engineer himself does not have faith in the LF measurement he makes, and he routinely states such in many reviews. So that's up in the air. Now, the mid and treble measurements are accurate(I have compared to NRC measurements when available to compare, and they have always been very close). Now, it is not accurate to refer to the treble as having a 4db peak. It would most accurately be referred to as a 2-2.25db peak. You would draw an imaginary straight line through the average levels across a wide frequency range and this would be the virtual reference/zero point. You would state deviations from this imaginary line, not based on the nearest narrow dip vs. the nearest peak relative to this.

-Chris
 
AcuDefTechGuy

AcuDefTechGuy

Audioholic Jedi
AcuDefTechGuy- could you shed any light on how you decode the Dolby bit stream from your cable or satellite box if indeed you do that? It's the last piece of the puzzle for me in your very original setup. Thanks.:)
Oooooh! Okay that makes sense. So theoretically, I could keep my Elite 94 and just add some preamps. I already have the Sunfire 5 channel. Hmmmm....

I mean it's sorda would be like "why are you doing all that" and there is a lot of duplication, but what the hell?
GREAT!

Now I'm Seriously thinking about getting the Denon 4308 to use for the following reasons:

1) 4 HDMI Inputs switching and 2 HDMI outputs - one to my 62" Mitsubishi and one to my "future" Optoma HD81LV projector.:D

2) Decoders for HDTV, HD Satellite, WiFi, HD Radio, Satellite Radio, FM/AM, etc.

3) Looks cool along with my other Denons.:D

I would connect the 4308's 5.1 Pre-Outs to the AUX2 Inputs of all 3 PMA2000IVRs.
 
AcuDefTechGuy

AcuDefTechGuy

Audioholic Jedi
Resonance on Salon2:

"The traces in fig.1 are free from the small discontinuities that would imply the existence of cabinet resonances of various kinds. Indeed, investigating the panels' vibrational behavior with a plastic-tape accelerometer uncovered very little untoward going on. The only mode I found (fig.2) was high enough in frequency and low enough in level to have no subjective consequences."

I got the impression that there were no significant cabinet resonance?
 
WmAx

WmAx

Audioholic Samurai
Resonance on Salon2:

"The traces in fig.1 are free from the small discontinuities that would imply the existence of cabinet resonances of various kinds. Indeed, investigating the panels' vibrational behavior with a plastic-tape accelerometer uncovered very little untoward going on. The only mode I found (fig.2) was high enough in frequency and low enough in level to have no subjective consequences."

I got the impression that there were no significant cabinet resonance?
I would recommend that you ignore anything the staff says in regards to subjective effects of measured performance, and view the actual measurements on their own. Stereophile rarely thinks any speakers have 'untoward' behavior, even when 3x the magnitude here, yet they make bold assertions about trivial issues like cables and what not.

-Chris
 
TLS Guy

TLS Guy

Audioholic Jedi
Could you please disect/interpret these measurements for me?

http://stereophile.com/floorloudspeakers/608revel/index5.html
The issue is time smear. You can get flat response with fourth order crossovers, but the mid is a whole cycle ahead of the woofer at 150 Hz and the tweeter a whole cycle ahead of the mid at 500 Hz. You can see this in the time domain graph.

Listeners have preferences for lower order filters as long as it can be achieved with accurate frequency response. I still have an issue with the passive crossover at 150 Hz. The response around the crossover is less than spectacular. I suspect the less than impressive listening reports are likely due to the time smear however.

If you presented that speaker with a square wave and recorded it, I bet it would be barely recognizable as such on the scope.

Not that any square wave from a speaker with multiple drivers looks in any way perfect, far from it, but it looks less and less recognizable as the order of the crossovers increase.
 
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