LS-9 and LS-6 digital crossover interest

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shotoons

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Re: LS-9 and LS-6 digital crossover interest
« Reply #20 on: 4 Jun 2015, 12:37 am »
guess I'm a bit daft so how does this work?

Digital source only, built-in dac, output 4 channels analog to amps, separate tweeter/woofer amping?
Volume control handled by?

HAL

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Re: LS-9 and LS-6 digital crossover interest
« Reply #21 on: 4 Jun 2015, 12:58 am »
Takes a stereo signal feed from either an analog source like a preamp, S/PDIF coaxial digital or USB2 asynchronous audio data from a PC or Mac.

There is a floating point DSP chip doing the signal processing for up to a 4 way crossover with time delay if needed.  Also other processing is available like parametric EQ.    Think of it as a Behringer DCX2496 digital crossover on steroids.  All 8 output channels are independently programmable.

Has four stereo 24bit/192KHz DAC's for 8 analog outputs that is balanced.

The analog outputs feed the power amps directly.  The amps then directly tie to the speaker drivers.  All the amplifier damping factor is now controlling the speaker motion.

Does that help?

Jerrin

Re: LS-9 and LS-6 digital crossover interest
« Reply #22 on: 4 Jun 2015, 02:02 am »
Add me to the list of interested folks HAL.   I'd like to hear some folks impressions of these verses their normal crossovers.

HAL

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Re: LS-9 and LS-6 digital crossover interest
« Reply #23 on: 4 Jun 2015, 02:14 am »
Will do. 

Might take awhile since volunteers with LS-9's and LS-6's with external crossover connections are needed for this one. 


Hugh

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Re: LS-9 and LS-6 digital crossover interest
« Reply #24 on: 4 Jun 2015, 03:22 am »
I may be able to help with this. :)

Will do. 

Might take awhile since volunteers with LS-9's and LS-6's with external crossover connections are needed for this one.

HAL

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Re: LS-9 and LS-6 digital crossover interest
« Reply #25 on: 4 Jun 2015, 03:34 am »
Hugh,
If it is the LS-9's, I can start the process. 

You just need to be able to biamp directly to the driver wiring inputs that would normally go to the crossover outputs.

Setting levels between tweeter and woofer amps, if they are different, should be doable with REW and a UMM-6 mic that I can send with the MS-2 demo computer.

Syrah

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Re: LS-9 and LS-6 digital crossover interest
« Reply #26 on: 4 Jun 2015, 03:13 pm »
Sorry for joining the party so late, but I'm very interested.  I have LS9s with external crossovers and I'm biamping them with 4 * Dodd 120 monoblocks - so consider me the perfect patient.

My initial plan when building these was to use a DEQX to crossover and EQ the bass arrays and use the stock passive crossover on the tweet arrays.  Danny talked me out of this as he was completely dead set against DEQ, but said that he would be open to it if someone could make one that was any good.  Danny built me a custom passive line level crossovers (really just one cap in the signal) to roll off the deep bass before going to the bass amps, this helped the overly exuberant bass that the LS9s were pumping out in my room.

Have you considered designing this for the bass section only?  Isn't that where the real room problems happen, and where less harm is done by a ADC/DAC conversion?  Although I suspect the issue could be creating a time delay if it is used for the bass only.

PS I've tried biamping with a pair of 200 CI Audio class D amps I have kicking around, and the 120 monoblocks sounded substantially better in my system.

Thanks,
Fraser

HAL

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Re: LS-9 and LS-6 digital crossover interest
« Reply #27 on: 4 Jun 2015, 03:26 pm »
I have done one install for bass only and it worked really well.

Danny has heard the dspMusik in his system with the latest BG driver two way with servo subs.  He was very impressed from what I discussed with him.  I had both a DCX2496 and DEQX and this is in a different level than either system.

The system can do time delay as well if needed.  Did that at Danny's with excellent results.

Syrah

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Re: LS-9 and LS-6 digital crossover interest
« Reply #28 on: 4 Jun 2015, 03:49 pm »
Thanks.  I suppose it can only create delay - it can't move time forward.   :scratch:

So if it's only hooked up to the bass drivers, and it has any inherent processing delay, it could lag the bass drivers behind the treble.

I've often worried about this issue using the DEQX - the extent to which processing through the unit creates delay, such that it doesn't work well unless it's hooked up to the tweeters as well.

I'm happy to be the guinea pig on this.

HAL

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Re: LS-9 and LS-6 digital crossover interest
« Reply #29 on: 4 Jun 2015, 03:53 pm »
That is why if it is used as the entire crossover it is not an issue. The processing time is very low for delay.

Will keep everyone posted

nickd

Re: LS-9 and LS-6 digital crossover interest
« Reply #30 on: 4 Jun 2015, 06:20 pm »
If I still had my LS-9's I would be considering the Lyngdorf TDAI 2170 to drive the NEO 8's and the SDA 2400 2 channel amp to drive the woofers. You get "room perfect" digital correction, Digital Crossover, time delay and tons of clean, cool running power. With built in state of the art on board DAC including USB and HDMI inputs. It seems like a dream come true.

HAL

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Re: LS-9 and LS-6 digital crossover interest
« Reply #31 on: 4 Jun 2015, 06:46 pm »
Considering the Lyngdorf system (processor and amp) you mention is $6499 for the two units and the dspMusik is $1500, would be an interesting comparison. 

I am still a proponent of correcting the room first with minimal digital correction.   A few PEQ's here do very well.   I put REW on the MS-3 PC Music Server and use a UMM-6 USB mic for the room measurements.  I make the measurements using the dspMusik as the output DAC for REW.


Danny Richie

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Re: LS-9 and LS-6 digital crossover interest
« Reply #32 on: 4 Jun 2015, 07:47 pm »
If I still had my LS-9's I would be considering the Lyngdorf TDAI 2170 to drive the NEO 8's and the SDA 2400 2 channel amp to drive the woofers. You get "room perfect" digital correction, Digital Crossover, time delay and tons of clean, cool running power. With built in state of the art on board DAC including USB and HDMI inputs. It seems like a dream come true.

Keep in mind that the digital "room correction" or "room perfect" correction is a bit misleading. I really see it more as a marketing gimmick than a real product. It is basically just an amplitude EQ. It doesn't correct room related reflections in any way. The reflections are all still there disrupting the sound stage and imaging. They have just been tuned down in the heavy areas.

Correction in this manor or in any regions above 200Hz or so is placement sensitive. In other words you can correct it for one point in space, but if you move over a foot in any direction it could be just as bad as it was before.

Syrah

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Re: LS-9 and LS-6 digital crossover interest
« Reply #33 on: 4 Jun 2015, 08:03 pm »
I've always prefered to first get my room as flat as possible with corner bass traps, first reflection absorbers, etc. and then to use DEQ for bass only.  That way it keeps all that processing out of treble regions that are more sensitive to digital corruption (ie. ADC/DAC).

But I'm curious as to how bad a delay is created by using a device like this on the woofer arrays (and subs) only.  That's why I stayed away from it last time.  It would be good if we could measure the delay that it creates (when the delay function is not used, obviously).  I recall your telling me that any small delay created when dealing with very low frequencies, like the sub, is unlikely to be a big deal because those waves are bigger - but it might be a big deal when we're up around the LS9 crossover point if the DEQ is delaying the woofers.

I couldn't find any figures for the DEQX, Berringer, etc. since all of the manufacturers contemplate the devices being used on every driver.

Danny Richie

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Re: LS-9 and LS-6 digital crossover interest
« Reply #34 on: 4 Jun 2015, 08:27 pm »
Let me just give you guys my feedback on Rich's product and what I learned from the listening comparatives we made.

First off, when comparing all of the digital crossovers out there to one another it is clear to me that what Rich has is a cut above all of the rest. There is no question about it. The quality of the DAC alone in Rich's unit is better than any of the others and compared to the lower cost units out there the difference is very significant. Rich's unit is the first and only digital crossover out there using a top level DAC.

The listening session we had also confirmed to me that passive crossovers are not the detriment many people would like to believe. Using Rich's DAC just as a passive DAC (like any other DAC) driving the speakers through the passive crossovers and then comparing it to Rich's DAC and digital crossover revealed very little differences.

The digital crossover had a slight disadvantage of having to use more amps and more interconnects and more speaker cable verses the passive crossover and single amps. Still I thought there were a few times that some things were a little farther outside the sound stage using the digital crossover, but not by much. Since the digital crossover allowed a finer adjustment of the phase between the main speakers and the servo subs towers there was better integration of the servo subs.

We used the digital crossovers to match the passive crossovers slopes and made them identical for the comparisons. However, the digital crossover could have been used to create different slopes and lower crossover points without any negative effects. Passive crossovers don't allow that kind of flexibility. So there is a lot of possibilities with the digital crossovers that can allow it to excel over a passive crossover in a lot of ways. 

Again it all came back to the quality of the DAC much more than whether the crossover was passive or digital. We had two other high level and really similar DAC's to compare to. My personal DAC shared some of the same guts as Rich's but there are a few things done to mine that took it up a notch. So for me the best overall sound was still with my DAC and a passive crossover. But the quality of the DAC in Rich's unit alone will make it a big improvement over 95% of everything out there even if you aren't using the digital crossover.

My recommendation for anyone with an LS-6 or LS-9 wanting to try Rich's unit is to get one from him and just try it as a stand alone DAC first. That's real easy to do. And chances are really high that it will be an improvement over your current DAC. If you like what you're hearing then you'll also like it as a crossover. Using it as a crossover will give you some slight improvements in a few areas and some powerful tools to correct room loading below 200Hz as well. But you will need more interconnects, more speaker cables, and more amplifiers.

HAL

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Re: LS-9 and LS-6 digital crossover interest
« Reply #35 on: 4 Jun 2015, 08:50 pm »
Thanks Danny for posting your observations! 

Syrah,
The time delay through the dspMusik is 0.000333 seconds.  It is a fixed delay time for all channels the way it works.

At the speed of sound in air at 1130ft/sec, that is 4.5" of distance offset. 

The system that uses the dspMusik for bass crossover are VMPS RM40 speakers and four subs.  The dspMusik runs the two woofers and four subs, and an active analog crossover runs the mids and tweeters.  At the crossover point of 309Hz in use, it is only a few degrees of phase difference.  No issues in that setup. 

At 800Hz and above, the phase offset starts coming into play.  That is around the frequency of the LS-9 crossover from woofers to tweeters.  That is why I recommend using it as the full crossover and not a bass management system.  That is well into the midrange.

The other way to do it is to use two channels of the dspMusik as just a DAC and run that to the amps driving the tweeter crossovers.  That way the time delay is maintained correctly to the original passive crossover to the tweeter if that is the preference.  You can still use all the features on the woofers like adding PEQ for mild room tuning without affecting the tweeter response. 

nickd

Re: LS-9 and LS-6 digital crossover interest
« Reply #36 on: 4 Jun 2015, 10:38 pm »
Quote
Keep in mind that the digital "room correction" or "room perfect" correction is a bit misleading. I really see it more as a marketing gimmick than a real product. It is basically just an amplitude EQ. It doesn't correct room related reflections in any way. The reflections are all still there disrupting the sound stage and imaging. They have just been tuned down in the heavy areas.

Correction in this manor or in any regions above 200Hz or so is placement sensitive. In other words you can correct it for one point in space, but if you move over a foot in any direction it could be just as bad as it was before.

I agree with Danny that EQ dos not correct room all room related reflections. However, I have heard it do amazing things in my room. I had a builder make a pair of 3 way loudspeakers with Digamoda amplifiers a couple of years ago. being able to dial in the bass with slope, Time delay and EQ all in the digital domain changed my mind quite a bit on DSP and ICE powered amps. Done right, it is quite amazing to hear what is possible with that technology. The user interface is a bit advanced and not really DYI friendly for the average builder. Best left to an experienced engineer IMOP. I had quite a bit of help in that area.

bdp24

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Re: LS-9 and LS-6 digital crossover interest
« Reply #37 on: 4 Jun 2015, 10:58 pm »
Okay, I'll admit that a lot of what is being said on this subject is over my head. But let me speak up for guys like me.....guys who have gone to great lengths to keep their music reproduction as "organic" (tubes yes, op-amps no) as possible. And we are now supposed to put a digital crossover in our music system? Ain't gonna happen. Yes, digital has improved, and perhaps when it gets above a certain bit rate/sampling frequency/whatever it is transparent. I send one of my tube pre-amp's outputs to my tube power amp which powers my loudspeakers from 180Hz up. The other pre-amp output goes to a DSPeaker 2.0 Dual Core (a digital room mode correction device) and on to Rythmik A370 amps which power GR Research 2-12 OB dipole subs from 180Hz down. The DSP 2.0 Dual Core is confined to frequencies of 180Hz and below, for which digital is fine. But a digital crossover through which frequencies above 180Hz pass? Surely you jest!

HAL

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Re: LS-9 and LS-6 digital crossover interest
« Reply #38 on: 4 Jun 2015, 11:14 pm »
No jest involved.

Until you hear a fully implemented no linear phase digital processing system including DAC's, you have not heard this capability. 

The only linear phase part are the A/D converters.  That is not used with the full digital system from Music Server to DAC outputs, just the analog inputs. 

At this point I use the MS-3 to dspMusik to PA's directly driving OB BG NEO3's, NEO10's drivers and GR-Research/Rythmik servo subs.  Sounds better than all the speakers I have tried in my setup and there have been many. 

In Danny's setup we used his small Dodd tube monoblocks on the tweeters and had Class D amp on the midranges and it sounded excellent with his new line arrays. 

So far it has been used with VMPS RM40, RM50, Sanders 10D, GR-Research N2X and moded V1's speakers with reported improved sonic results.   





HAL

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Re: LS-9 and LS-6 digital crossover interest
« Reply #39 on: 5 Jun 2015, 01:11 pm »
Setting up my CLIO measurement setup today and have the LS-9 crossover on the bench. 

Will get the setup working and see what I can do.