Does DSP belong in State of the Art Systems?

tony22

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There are two sets of graphs, the darker ones are before DSP, the lighter ones after. I don’t see any peaks in the after DSP graph, just the dips that are caused by the room and a gradual Harmon curve slope
Right. I'm referring to the area circled in black. It looks like a bit of boost was used to correct these dips.

DSP WBF.jpg
 

PGA

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If you look closely at the magnified chart the light blue and red lines are pretty much at the Harmon target curve. Also there is no boost. Just attenuation in the DSP. Notice there is quite a lot of attenuation in the deep bass. This translates into additional headroom. And even above the Schroeder frequency the DSP is helpful.
 

schlager

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tony22, it is quite unproblematic to flatten the frequency response below 100 Hz, as it is primarily what is called minimum phase issues and can thus be corrected for without a penalty. You will of course have to keep an eye on not over powering the speakers and in this example it is only a mild boost above aprox. 50 Hz. In generel, well done EQ, will not require more power from the amp, than a non corrected speaker.
 
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PGA

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tony22, it is quite unproblematic to flatten the frequency response below 100 Hz, as it is primarily what is called minimum phase issues and can thus be corrected for without a penalty. You will of course have to keep an eye on not over powering the speakers and in this example it is only a mild boost above aprox. 50 Hz. In generel, well done EQ, will not require more power from the amp, than a non corrected speaker.
 

PGA

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The two Benchmark amps driving the dual 10” woofers are wired directly to the drivers in each TAD R1 with no passive LPF in the way. The amps are in bridged mono mode and don’t ever clip. The LPF for the woofers is implemented in the Pass XVR1. Andrew Jones set this up for me.
 

tony22

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If you look closely at the magnified chart the light blue and red lines are pretty much at the Harmon target curve. Also there is no boost. Just attenuation in the DSP. Notice there is quite a lot of attenuation in the deep bass. This translates into additional headroom. And even above the Schroeder frequency the DSP is helpful.
Head smack! :rolleyes: I did miss seeing the light blue line amidst the others. Sorry for the confusion!
 

Don Reid

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I really don't see DSP technology being useful beyond being a crossover. Its not like your living room is a stadium and you need a DSP to time align speaker clusters together.
With my DIY fully horn loaded speakers the bass is reproduced by folded corner horns back in the room corners where they need to be. Mids and highs are reproduced by by horns out in the room where they image better. This is essential to my design of the speakers. Counting the horn path inside the folded bass horns plus the physical separation between the bass horns and the mid range drivers the two are separated by over sixteen feet. My DEQX DSP corrects this to sound as though the acoustic centers of the woofers and mid range drivers are within less than 3 mm (less than 1/8") of each other. This is only one of the important functions DSP provides in addition to crossovers.
 

sparkie

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With my DIY fully horn loaded speakers the bass is reproduced by folded corner horns back in the room corners where they need to be. Mids and highs are reproduced by by horns out in the room where they image better. This is essential to my design of the speakers. Counting the horn path inside the folded bass horns plus the physical separation between the bass horns and the mid range drivers the two are separated by over sixteen feet. My DEQX DSP corrects this to sound as though the acoustic centers of the woofers and mid range drivers are within less than 3 mm (less than 1/8") of each other. This is only one of the important functions DSP provides in addition to crossovers.
Strange setup, but never the less, the DSP has always been the go to to correct the situation since the mid 80s. Its only been recently the technology has been trickling into other areas of audio. Its only been recently that its price to build the circuit has gone down enough to be integrated into powered speakers.
 

Lagonda

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I think it is really telling that none of the systems that credit dsp for their "great" sound are state of the art and mostly some version of digital/ diy ! :rolleyes:
 

schlager

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Lalongo, what criteria do you have, as premise for state of the art equipment?
 

Lagonda

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Lalongo, what criteria do you have, as premise for state of the art equipment?
The equipment the rest of us talk about ! I do not se anyone with top of the line Dartzeel, Ch ,Dagostino MBL, Koda or any of the high quality SET systems using active dsp on treble and midrange. ;)
 
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schlager

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Lagonda, I hope your hearing is better than your avatar :D
 

PGA

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I think it is really telling that none of the systems that credit dsp for their "great" sound are state of the art and mostly some version of digital/ diy ! :rolleyes:
I would have thought TAD R1s, Berkeley Reference DAC and Constellation Centaur Mono were close enough to state of the art, at least back when I first owned them.

My sample size is just one, but in my case judicious application of DSP made a huge difference. Switching cables, amps and DACs made small differences.

I prefer the Benchmark Meitner combo over the Constellation Berkeley. Some may argue I took a step down. I disagree

The modifications to the TADs and the set up of the Pass crossover were all as specified by the man that designed the R1s, so I would hardly call that DIY.

I owned over the years top of the line MSB, Pass and Spectral gear. Again the differences were subtle. Mostly a waste of time to switch from one to another as they were all quite good.

Most importantly none of these changes addressed the issues regarding frequency response that can now be much improved with proper DSP.
 

Lagonda

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Lagonda

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I would have thought TAD R1s, Berkeley Reference DAC and Constellation Centaur Mono were close enough to state of the art, at least back when I first owned them.

My sample size is just one, but in my case judicious application of DSP made a huge difference. Switching cables, amps and DACs made small differences.

I prefer the Benchmark Meitner combo over the Constellation Berkeley. Some may argue I took a step down. I disagree

The modifications to the TADs and the set up of the Pass crossover were all as specified by the man that designed the R1s, so I would hardly call that DIY.

I owned over the years top of the line MSB, Pass and Spectral gear. Again the differences were subtle. Mostly a waste of time to switch from one to another as they were all quite good.

Most importantly none of these changes addressed the issues regarding frequency response that can now be much improved with proper DSP.
And what are you using now, in your dsp'd system ?
 

schlager

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Lagonda, you may be an audiophool......sorry audiophile, that was a typo,
but at least you have humor :p
 
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PGA

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And what are you using now, in your dsp'd system ?
Roon, Meitner MA3 (source via Ethernet), Pass XVR1, 4 Benchmark AHB2 amps in mono, TAD R1s with the woofer LPFs bypassed. Pass XVR1 was set up by Andrew Jones, as a personal favor. This is a very complicated thing to do, I would not try to DIY this step. The passive HPF for the coax TAD driver remain stock. Convolution filter was designed by Mitch Barnett. Room treatments are all RPG with setup designed by RPG.

Coincidentally the AHB2s were designed by Andrew's twin brother. These are fantastic amps. I much prefer them to all my previous amps and they were a fraction of the price, weight, heat and power consumption (in Florida this matters).

Andrew Jones preferred we implement the crossover in the analogue domain. This simplified things somewhat (just need one DAC). Digital purists may disagree and there are things we could have done in the digital domain that cannot be done with a Pass XVR1. Maybe at some point I'll try a fully digital crossover, but for now this sounds fine.

In my experience, you need a professional setting up your DSP and the stuff that's built into consumer products doesn't even come close to what can be done now with a proper convolution filter running in a computer (in my case in the Roon NUC).
 

Lagonda

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Roon, Meitner MA3 (source via Ethernet), Pass XVR1, 4 Benchmark AHB2 amps in mono, TAD R1s with the woofer LPFs bypassed. Pass XVR1 was set up by Andrew Jones, as a personal favor. This is a very complicated thing to do, I would not try to DIY this step. The passive HPF for the coax TAD driver remain stock. Convolution filter was designed by Mitch Barnett. Room treatments are all RPG with setup designed by RPG.

Coincidentally the AHB2s were designed by Andrew's twin brother. These are fantastic amps. I much prefer them to all my previous amps and they were a fraction of the price, weight, heat and power consumption (in Florida this matters).

Andrew Jones preferred we implement the crossover in the analogue domain. This simplified things somewhat (just need one DAC). Digital purists may disagree and there are things we could have done in the digital domain that cannot be done with a Pass XVR1. Maybe at some point I'll try a fully digital crossover, but for now this sounds fine.

In my experience, you need a professional setting up your DSP and the stuff that's built into consumer products doesn't even come close to what can be done now with a proper convolution filter running in a computer (in my case in the Roon NUC).
Nice system ! You prove my point, no dsp in the higher frequencies, and the XVR1 is a state of the art analog crossover, i don't understand why they stopped making it, to bad :)
 

SeagoatLeo

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May I suggest an additional non-DSP product for enhancing even the best dispersing speakers like my Legacy Signature IIIs and Von Schweikert VR9 SE Mk2s. I have been using a pair of Shakti Hallographs for several decades, one pair in the corner front walls and the other pair close to the middle of both side walls. Angled correctly, they enhance both the open and direct sound of the speakers. Set up by the manufacturer.
 

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