As you all know, these three processors are virtually identical. It appears Audioholics.com has managed to acquire a new sample with the hardware fixes from Sherbourn. I am looking forward to this review.

In the meantime, take a look at their FAQ on this product.

http://www.audioholics.com/FAQs/SherbournP7000.php

I sure wish the damn thing would allow sub out in two channel with the mains set to large. Oh well.

Some interesting tidbits there:



There was an (somewhat incorrect, imo) article at Secrets a little while ago about why individual crossovers were a bad thing. One of the *conjectures*, was that if you had say, 60 Hz mains, 120 Hz center, 80 Hz surrounds/rears, set, that the global low pass filter to the sub might be that lowest setting or 60Hz. That would leave a "hole" for example in the center channel, 60 - 120 Hz. At least by the above, that is not true for the 950/AT/Sherbourn units.

But I guess I do wonder, if the low pass to the sub is 120 Hz in this case, is that also for the mains, so that there'd be "doubling" from 60 to 120 Hz? I.e., the low pass to the sub should *not* be a global value, but it should the same value for each channel as what the respective high pass filter is.

I actually know of a way to test this, but just haven't gotten around to it yet...



I don't know about your 950, but mine also has CES modes for DTS 5.1 too.

From everything that I read on the 950 it is a TRIPLE crossover. That means there are 3. If it was a global sub low pass and variable high pass for the sattelites, it would not be the triple crossover as described by Outlaw. They have 3 crossovers in the 950 (as I read it). One for the mains, one for the center, and one for the surrounds. This is because many owners have different speakers for each of these catagories.

Each crossover can be set individually, depending on the abilities of your speakers. For each of the 3 crossovers, the low pass side goes to the sub. So the sub handles (for instance) 100hz and below that was meant for the surround channels, 80hz and below that was slated for the center channel, and 40hz and below that would normally go to the tower mains (that is, if that is the configuration you had set the crossovers at). There is no "hole" or "doubling". The sub simply produces the frequency of each channel that the other 5 cannot produce, based on each of the 3 crossover settings.

This is what the manual says about it:




That certainly leaves things up in the air. I don't think the outlaws have confirmed the way it works. I haven't really been keeping up, so they might have posted something about it, but a quick search didn't show anything.


brianca

Let's use a configuration scenario to help explain how the triple cross-over function works.

Settings:

All speakers set to small. (A Large setting by-passes the cross-over function for that speaker)
Front: 40Hz
Center: 80Hz
Surrounds: 100Hz
Sub: ON

In this configuration the sub will see the entire LFE or ".1" signal. It will also receive any signal below 40Hz from the front speakers, any signal below 80Hz from the center channel and any signal below 100Hz from the surrounds.



[This message has been edited by Scott (edited February 14, 2003).]

And (correct me if I'm wrong, Scott), this applies to the scenario when all speakers are set to "small" -- if, for instance, the center channel in the example above was set to "large" the sub would receive the ".1" data, everything below 40Hz from the mains, and everything below 100Hz from the surrounds, but nothing from the center.

Right?

------------------
gonk -- Saloon Links | Pre/Pro Comparison Chart | 950 Review

Thank you Scott!!

Hello Gonk,

You're correct. I've added that info to my example, thanks!

Scott

Thanks, Scott.

I guess that's another difference between the two.

brianca..

Brianca,

How so?

Scott

based on the statements above, it appears that the sherborn sets the sub LPC at the level of the highest of the three HPCs. of course that could be false, I was just going on what the article said.


brianca..

[This message has been edited by brianca (edited February 14, 2003).]

Kevin, Depends on the material that is being processed (bass management, not surround processing). With discrete multi-channel sources, full range content in each channel exists in the recording. Where ever you set the crossover for each channel, the frequencies below that point should be moved to the subwoofer output. You can set your subwoofer's crossover as high as you want, but the only content to reach the sub should be the frequencies shaved off the other channels. So if you're crossing over your mains at 40Hz, then the subwoofer output should only be putting out content below 40Hz, whether the subwoofer's crossover is set at 40Hz or 400Hz. For there to be bass "doubling", the processor would have to actually generate some duplicate bass content.

With matrix derived sources, it's a different story. Here the processor IS generating additional channels (including the sub). Mind you, the contents of these channels are 100% from the original 2-channel recording (i.e., no generated sounds, echos or reverbs), but the channels themselves are generated by the matrix decoding process.

I used to think that modern matrix decoders (like Neo:6 and PL II) used to first generate 5 full range channels, which would then be bass managed into a 5.1 speaker set-up. However, it turned out to work a little differently than that. In receivers and processor I've had experience with, the matrix decoders did not generated full range signals for every channel unless they were all set to 'large'. If any of them were set to 'small', they got a derived signal that only contained sounds above the crossover point. It's not like that channel was full-range content that existed discretely on the recording. Since it this derived channel never had full-range content, there's no bass to move around. Each channel gets only what's above the crossover point.

So what comes out of the subwoofer output? It's another generated channel, made by summing the original 2 channels of the recording. As with the other derived channels, it will only receive content based on where its crossover is set. There's no need to take frequencies above this crossover point and move them to the main channels because there were no sounds above that crossover point to begin with; i.e., this isn't discrete content from the original recording, like a .1 LFE channel is.

In both cases, I think it's best to set the subwoofer crossover to the same setting as the highest crossover point of the other channels. If the processor is performing bass management correctly, you shouldn't be getting any duplication.

Best,
Sanjay

I thought there was a LPF on the sub at 120 Hz as per DD (DTS/XYZ/?) specs, that was distinct from the triple crossover - IOW a 3000 Hz signal on the .1 would be attenuated by this LPF. Am I wrong? If not, could this be the root of some confusion?

I use distinct crossover fequencies for each of the three sets of channels. It works for me.

However, when switching between 2.1 (e.g. stereo with sub) and 5.1, I encountered a phase shift problem with the subwoofer. As I recall others noticed the same in their set up, when going from mutlichannel to stereo+sub, but it could be problem with the overall room layout, not a pre/pro problem.

Mine works exactly as I described, or as Scott did a better job of describing. I even checked by unplugging channels from the ampindividually and checking the crossovers and how they worked. Flawless.

Hey folks, just to let you know, the Outlaw, Sherbourn and Atlantic all function identically. They have the same exact DSP engine, firmware, and analog design. There really are no differences other than cosmetics. I heard the Blue Dot rev was actually a result of Sherbourn Engineering helping East Tech with cleaning up the analog design.

If you think about it, the Outlaw is the true bargain of the three since it is the cheapest. Thats my take.

Scott- Awesome! (I really mean that, because that means that Brian Florian of Secrets doesn't know what he's talking about, at least as far as the 950 goes...)

I always took that separate 120 Hz value as the low pass for the LFE (0.1) channel, *not* of the crossed over info from the mains, center, surrounds, rears. So the LFE channel isn't allowed to go full range to the sub, which doesn't make sense anyway. But the way that FAQ read, I wasn't sure in terms of how they referenced it. (Tidbit for the Outlaws: the Sony TA-E9000ES allowed you to choose that number. I believe 120, 150, 200 Hz were the choices.)

Cool!

Hey KCB,

Did you get a resolution to the phase shift?

Will

Yeah, that's what I assumed as well, but I can see how it might be confusing - heck, BM is confusing enough as it is. I don't really understand WHY there is a LPF on LFE, (other than a reference to a spec I saw) but I guess it won't hurt, most of the time.

I just came from the H/K website. They claim a triple crossover, but it is only high pass. Then a seperate low pass must be selected for the sub. H/K cautions that the subs low pass must be set at the highest of the triplc crossover settings to avoid creating a bass hole. This would indeed cause a bass doubling in the mains if they were set to crossover at a frequency lower than the sub's crossover. Why the hell would they do something stupid like that???

Maybe this is a misunderstanding.... The subwoofer's low pass must be set to at least the highest of the triple crossover settings, even when connected to a 950, to avoid creating a bass hole. The subwoofer's low pass frequency affects the highest frequecy that passes out of the subwoofer.

Will

Well, I guess that's what they said, when you get down to it (if the paraphrase was correct) but it's a confusing bit of advice and should be well explained. HK usually has things done right, but you never know.

http://manuals.harman.com/hk/Owner%27s%20Manual/AVR%20325,525,4550,5550%20insert%20(FINAL).pdf

I read that as they have high pass settings for the mains, center, and surrounds, and a seperate low pass for the sub. Nowhere does it say to set the sub's own crossover above the highest crossover frequency. It says the H/K has a seperate sub crossover.

This sounds like exactly what they're saying to me [from the linked manual page]:

It sounds to me like they provide one on the H/K. It does not say the sub's crossover...it says "a seperate setting is provided to tailor the output of the AVR"

Hmm. It is ambiguous, but it could easily be interpreted to mean they did the right thing [that's actually what I would have read into it] so, given the level of technical ability, attention to detail and quality generally associated with H/K I would assume they got it right until shown different.

Is there other info or manual pages that lead you to to believe it's as badly done as you suspect, or was this just the first impression you got from the linked page?

Will- It still is as I found:

If you adjust the sub to be in phase with the mains when using the digital crossover on the 950, and then switch to the 80 Hz analog crossover for the 5.1 inputs, the sub is now approx 180 deg out of phase. About 4 other people have confirmed this (you being one ).

My sub has a variable phase knob and an inverted input. For now, I've been twiddling the knob back and forth when switching between CD/DVD-V and SACD/DVD-A. But I have one of those A/B/C RCA switches on the way, and I'll just switch between the 2 inputs on my sub. A little bit more convenient. The C position, no output to the sub, will take care of the "double bass" when using 2 channel bypass.

Also, the *best* way I've found to check this is with this disc:

http://www.chesky.com/catalog/body_catalogdtl.cfm?PRODUCT=100274&CATEGORY=1

Has phase tests for the specific crossover you're using, for DVD-A and DVD-V. Actually easier to use than the discrete test tone disc I was using.

[This message has been edited by Kevin C Brown (edited February 15, 2003).]

As you know, it can get quite obvious when the sub is phase inverted from the other speakers: the sound seems to drift all over the place.

This was a problem in the original 950. I hoped they'd fix it in the blue dot, but I guess not.

I have to physically walk to my sub and invert my sub's phase switch in back, when I switch mode in the 950, or else the sound is drifty.

I'm thinking I'll just do everything between the preamp and amps, since there seems to be little hope of a universal solution in a can in the forseeable future. A few active crossovers, a mixer ot two, I think I can get what I want. What a PITA though.

It probably won't happen in this house, or at least not for a long while.

Kevin...I also am getting a phase reversal when switching from my ICBM analog BM and the A/V receivers digital BM. Where can I get one of those A/B/C RCA switches?

Mike Sloan
solomon57@aol.com

Mike- I'm getting something like this:

http://www.mcmelectronics.com/Home/level_5.jhtml?PRODID=35624&SKUID=34868

The picture has 4 inputs, but if you read the description, it's 3 inputs.

any time there is a summing, discrete status is lost. the filters in digital bass management are just that...NOT crossovers.

the HPFs applied to the satellites allow highs to pass, 1 filter applied to each of the 5 (thus, the 5 retain discrete status).

a duplicate signal is sent to a summing block where the LPF is applied (in the case of the triple crossover, three seperate summing blocks).

a final summing block sums the composite redirected bass signal with the LFE signal. thus, the lfe is no longer a discrete channel. the newly created composite signal is called subwoofer.

and then there is the genius who decided to place all of the sub's controls on the BACK panel.

Or, if you really want to dig into it, at some level a set of data buffers (addresses and size, probably) are passed to a sub-routine that sums them, then the resulting buffer is passed to a routine that performs the LPF.....

Only the CVS guy knows for sure.

Welcome to digital audio.

If someone had asked a few minutes ago to define a cross-over I would have said an assembly consisting of one or more filters. What is your definition? Or did I not understand the point?

Yeah, the term gets misused sometimes, but I always thought of a crossover as the combination of a HPF and a LPF splitting the signal between a sub and high(er) freq speakers...

Well, that would certainly be an example of a crossover (from my understanding) but the common case of a passive network that splits signal into 2 or more bands in a typical loudspeaker was a crossover last time I checked. After careful thought I'm guessing maybe it's the act of signal summing that BoB feels prevents the typical BM setup from being a true crossover?

I'd submit for consideration the classic passive stereo satellites plus a DVC sub-woofer as a litmus test - is it or is it not a crossover, if so or not, why?

I've always had a liberal view of the term, but I'm willing to be educated. I suspect it's maybe one of thise things that there may be no hard and fast rules for use of the term.

it's just easier to get a handle on digital bass management if you use the term 'filters' instead of a crossover.

actually it's an infinite impulse response (IIR)filter that sets the slope and corner frequencies for the high and low pass filters. the 5 full range signals are high passed and then sent to the respective satellites (where they are then passed through a passive 2 way or 3 way crossover in most cases). that full range signal is not passed through a crossover network.

5 duplicate full range signals are summed and level adjusted to create a composite signal. this composite signal is then low pass filtered and then summed with the LFE signal, which has also been level adjusted and low pass filtered. this creates a single digital bass signal which is now called subwoofer.

if that's a 'crossover', then i don't know what kind it is. i prefer to call it a virtual routing scheme of volume knobs, y jacks and filters. it's main selling point is that it's smaller than analog circuits. i suspect that's because the only other points are negative ones.

If it's ever easy.

The current state of things is more complicated IMO due to poor design rather than implementation. The basic concept is flawed at the core, so all the other stuff we do end up being more like bandaids than fixes.

You guys are a great read. This thread has certainly opened my eyes.

I have read about crossovers but now I am beginning to understand.

Keep this up and Outlaw will have a solution and maybe pay you guys royalties.

What if we had a configuration like this:

Settings:

Front speakers set to Large.
All other speakers set to small.
Front: N/A (bypassed because of Large setting)
Center: 80Hz
Surrounds: 100Hz
Sub: OFF

What happens to the frequencies below the crossover points for the Center and Surround speakers?

In that scenario, all low frequency material from center and surrounds is redirected to the front speakers, along with the LFE channel information.

------------------
gonk -- Saloon Links | Pre/Pro Comparison Chart | 950 Review

I'm wondering how or if the EPROM fix will get delivered to customers who bought Outlaw 950 clones from Sherbourn and Atlantic. How are the clone resellers handling this?

Does anyone here in the Outlaw Saloon have Atlantic Technology's or Sherbourn's clone of the Outlaw 950?

Will:

Why don't you ask the people in the Atlantic Technology or Sherbourne user forums? Opps, don't they have those sorts of things?

But what do I know, I'm only a dog!

ARF ARF says Iggy

Iggy,

I have not heard of any Atlantic Technology or Sherbourn forum. But what do I know?

Will