Does DSP belong in State of the Art Systems?

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 :)
DSP is applied full bandwidth. This was contrary to Andrew Jones’s advice. That said, the TAD coax did benefit from a little smoothing and shaping.

Having gone through this experience, selling a $20,000 system without educating the customer on DSP and offering a basic convolution filter to them is nothing less than malpractice. I agree that you’re not going to tranform a poor system to a great system, but without DSP you’ll never know how good a great system actually will sound.
 
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DSP is applied full bandwidth. This was contrary to Andrew Jones’s advice. That said, the TAD coax did benefit from a little smoothing and shaping.

Having gone through this experience, selling a $20,000 system without educating the customer on DSP and offering a basic convolution filter to them is nothing less than malpractice. I agree that you’re not going to tranform a poor system to a great system, but without DSP you’ll never know how good a great system actually will sound.
In a very difficult room maybe. In a decent sized room without big problems in the low frequencies, using mostly high quality analog sources i don't want the degradation that digital brings to the high frequencies. Using some dsp on the bass amplifiers is not out of the question if it can be done seamlessly.
 
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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 :)
They stopped making XVR-1 because they ran out of some critical parts that couldn’t be obtained from another supplier.
I’ve had one and when wanted to buy a second unit, that’s what Kent English told me.
 
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What's your RT60 and Clarity measurements look like in that room? My experience is that for a really smooth response to sound natural the room has to be pretty tight with a very fast RT60. A more lively room I've found must be allowed to have the ups and downs it naturally does, at least for my tastes. I'd definitely get after that peak at 30 Hz because it's broad. But those narrow ones seem to be required to keep the vibrance alive. I've gotten response to look like that too but it's just too tight sounding for me. It's interesting and beautiful in it's own way but it just feels like the speakers are getting pinched too much. Maybe it's Stockholm syndrome and I've come to identify with room effects. Of course I haven't done it with Mitch's expertise. I don't have that software. I use a Mac Mini and I don't think that runs on a Mac.
 
Tim Link, Audiolense don't run an a Mac, but the convolution filter can. So you can have your filters generated by Mitch Barnett or any other providing that service and then run it from your Mac. Or simply buy a Windows PC, even an old cheap one would suffice, but you will have to check with the Audiolense requirements.
 
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They stopped making XVR-1 because they ran out of some critical parts that couldn’t be obtained from another supplier.
I’ve had one and when wanted to buy a second unit, that’s what Kent English told me.
True, but they surely could make a modern version of it using modern parts. The real answer I suspect is there is very little demand. Every now and then used ones show up for around 5000. That’s how I got mine. Kent checked the unit to make sure it was working to spec. All no charge,

Pass had single ended crossovers under the First Watt brand available until a couple years ago. I believe they still white label these for a speaker manufacture. When I spoke with Nelson he suggested I buy the circuit boards for the single ended units and make one myself …. with my soldering skills, that would not have worked out!
 
What's your RT60 and Clarity measurements look like in that room? My experience is that for a really smooth response to sound natural the room has to be pretty tight with a very fast RT60. A more lively room I've found must be allowed to have the ups and downs it naturally does, at least for my tastes. I'd definitely get after that peak at 30 Hz because it's broad. But those narrow ones seem to be required to keep the vibrance alive. I've gotten response to look like that too but it's just too tight sounding for me. It's interesting and beautiful in its own way but it just feels like the speakers are getting pinched too much. Maybe it's Stockholm syndrome and I've come to identify with room effects. Of course I haven't done it with Mitch's expertise. I don't have that software. I use a Mac Mini and I don't think that runs on a Mac.
I don’t have the numbers, but if anything the room is a little on the over damped side. Mitch Barnett did look at the RT60 and waterfall plots. His assessment was that the room was on the dry side but within spec for what you’d have in a mastering studio. It sounds great with R1s. It was not great with Mágico Q5s.
 
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Tim Link, Audiolense don't run an a Mac, but the convolution filter can. So you can have your filters generated by Mitch Barnett or any other providing that service and then run it from your Mac. Or simply buy a Windows PC, even an old cheap one would suffice, but you will have to check with the Audiolense requirements.
Thanks! So that's an option as I'm already setup to run the convolution filter. My system is a strange one so it'd be interesting to see what he would come up with.
 
Tim, if you want to get your feet wet, I can generate some filters for you, free of charge :D All you need to do is take left and right measurements of your speakers in the listening position and export them as wav files. REW can do that, or just send me the mdat REW file.Then I can generate different filters with different time windows. PM me if you are interested.
 
DSP/EQ crash course for Dummies.

EQ is for adjusting the room impact in the bass and correct the speakers near field response over aprox. 500 Hz. It sounds most natural, if the sound from the speakers has approximately the same timbre as live musicians would get when performing in the same room. It is also important that the dispersion pattern from the loudspeakers is fairly constant with frequency, so that reflected sound and reverberation do not have a completely different timbre to the direct sound. A good target curve falls by about 1 dB/octave, but is room, speaker and listening distance dependant. This tilt is the normal frequency response in a normal listening room, of a loudspeaker with a flat on-axis frequency response, when measured in an anechoic chamber and with a fairly normal dispersion characteristic. If you eq it to a flat response in the listening room, it is the same as a speaker with a rising frequency response on the axis in an anechoic room - i.e. thin and shrill sound, and then definitely a speaker that "measures poorly". Again, this is very well known, and no one who has played with eq and understands a bit of what they are doing, would set up a system like this.

So what EQ can do for your frequency response, is to even out the room impact and the often relatively nonlinear near field response from the speaker. If we translate it to the more traditional part of hifi where you share listening impressions, we can perhaps compare it to a sound were "nothing sticks out". When people write this about a sound experience, it is usually a positive characteristic.

But then again, in this idiosyncratic hobby, for many it is precisely a point, that the system should produce a sound, in addition to the original signal, aka all these buzzwords as "warmth", "soul", "human connection", "musicality" that should be added to all parts of the playback.
The rest of us who just wants to listen to the music and not the system, we want to have it reproduced as it was intended/recorded.
 
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Good write up. Personally I've seen (among those who've done EQ) far too many rooms that measure dead flat in FR. To my ears they've all sounded terrible.
 
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Yes, hence the room target curve becomes a critical point, where small adjustment of 0,1 dB over the entire audio frequency band, aka very broad Q (small number Q), is audible. This room tilt is paramount, to get the right overall sound balance, but is often overlooked or ignored. One will have a hard time changing the room tilt without the use of EQ. Knowledge is your hifi friend.
 
Tim, if you want to get your feet wet, I can generate some filters for you, free of charge :D All you need to do is take left and right measurements of your speakers in the listening position and export them as wav files. REW can do that, or just send me the mdat REW file.Then I can generate different filters with different time windows. PM me if you are interested.
I think I'd be a fool to not take you up on this.
 
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Yes, hence the room target curve becomes a critical point, where small adjustment of 0,1 dB over the entire audio frequency band, aka very broad Q (small number Q), is audible. This room tilt is paramount, to get the right overall sound balance, but is often overlooked or ignored. One will have a hard time changing the room tilt without the use of EQ. Knowledge is your hifi friend.
Much more effective and predictable to tweak your target curve to dial in your system versus swapping cables, interconnects, DACs and amps.
 
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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:
That's absolutely right. Few high end systems include "room correction DSP" because they are likely to be feeding similarly high end speakers. The better the system (provided it's set up properly in a sympathetically furnished room), the less the need for DSP.

Also as you say, it's a boon to DIY speaker builders who don't have the R&D and testing facilities for multiple prototypes to get an ideal response from their home-builds. Here DSP will be of enormous help. It also helps with poor / mediocre branded speakers where corners are cut, although it still won't match a well constructed and designed branded one of much the same size.

The other place where DSP may be helpful is with Home Theatre multi-speaker systems where the owner is unlikely to have the skills to set up his system for best performance. It's not easy, so resorting to DSP is almost forgivable, particularly because in HT system the audio is only part of the performance and our brains are less critical of less-than-perfect sound if they are also processing the video sensation.

However, DSP can be beneficial without spoiling the delicate signal if it's used in an active system where only the bass frequencies are sent to a dedicated bass-only amplifier that serves the bass drivers. My own speakers have this DSP facility though the software is not intuitive so I am not even using this - let alone Dirac Live.

In your later post referring to analogue, surely no one who is a true analogue fan would ever use DSP in their system as it involves analogue to digital conversion, then DSP, then digital to analogue conversion? Better perhaps to ditch the analogue source and start off with digital and thus cut out the ADC. The more a signal is processed, the more it will suffer damage.

Others (users of DSP) will disagree of course!
 
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That's absolutely right. Few high end systems include "room correction DSP" because they are likely to be feeding similarly high end speakers. The better the system (provided it's set up properly in a sympathetically furnished room), the less the need for DSP.

Also as you say, it's a boon to DIY speaker builders who don't have the R&D and testing facilities for multiple prototypes to get an ideal response from their home-builds. Here DSP will be of enormous help. It also helps with poor / mediocre branded speakers where corners are cut, although it still won't match a well constructed and designed branded one of much the same size.

The other place where DSP may be helpful is with Home Theatre multi-speaker systems where the owner is unlikely to have the skills to set up his system for best performance. It's not easy, so resorting to DSP is almost forgivable, particularly because in HT system the audio is only part of the performance and our brains are less critical of less-than-perfect sound if they are also processing the video sensation.

However, DSP can be beneficial without spoiling the delicate signal if it's used in an active system where only the bass frequencies are sent to a dedicated bass-only amplifier that serves the bass drivers. My own speakers have this DSP facility though the software is not intuitive so I am not even using this - let alone Dirac Live.

In your later post referring to analogue, surely no one who is a true analogue fan would ever use DSP in their system as it involves analogue to digital conversion, then DSP, then digital to analogue conversion? Better perhaps to ditch the analogue source and start off with digital and thus cut out the ADC. The more a signal is processed, the more it will suffer damage.

Others (users of DSP) will disagree of course!

Have you ever used DSP? I think that your fears of analog to digital and digital to analog conversions are overblown and the benefits of DSP greatly outweigh any minuscule loses suffered in these conversions. You should try it, I bet that you would be surprised by your own findings.
 
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That's absolutely right. Few high end systems include "room correction DSP" because they are likely to be feeding similarly high end speakers. The better the system (provided it's set up properly in a sympathetically furnished room), the less the need for DSP.

Also as you say, it's a boon to DIY speaker builders who don't have the R&D and testing facilities for multiple prototypes to get an ideal response from their home-builds. Here DSP will be of enormous help. It also helps with poor / mediocre branded speakers where corners are cut, although it still won't match a well constructed and designed branded one of much the same size.

The other place where DSP may be helpful is with Home Theatre multi-speaker systems where the owner is unlikely to have the skills to set up his system for best performance. It's not easy, so resorting to DSP is almost forgivable, particularly because in HT system the audio is only part of the performance and our brains are less critical of less-than-perfect sound if they are also processing the video sensation.

However, DSP can be beneficial without spoiling the delicate signal if it's used in an active system where only the bass frequencies are sent to a dedicated bass-only amplifier that serves the bass drivers. My own speakers have this DSP facility though the software is not intuitive so I am not even using this - let alone Dirac Live.

In your later post referring to analogue, surely no one who is a true analogue fan would ever use DSP in their system as it involves analogue to digital conversion, then DSP, then digital to analogue conversion? Better perhaps to ditch the analogue source and start off with digital and thus cut out the ADC. The more a signal is processed, the more it will suffer damage.

Others (users of DSP) will disagree of course!
That would be throwing the baby out with the bath water, ditching the analogue source ! :eek:
 
Have you ever used DSP? I think that your fear of analog to digital and digital to analog conversions are overblown and the benefits of DSP greatly outweigh any minuscule loses suffered in these conversions. You should try it, I bet that you would be surprised by your own findings.
In fact I've used Dirac Live (in my current NAD amp), RoomPerfect (in a Lyngdorf amp), MARS (in a Micromega amp) Anthem (in the bass amp of Martin Logan speakers) and XD (in my Avantgarde speakers bass amps). I owned all of these apart from the home demo Lyngdorf.

The only ones I'd consider using are those built into bass amps - Anthem in Martin Logan and XD in Avantgarde, as the top end is sent un-DSP'd directly to the mid and top speakers.

My numerous filters taken after either the supplied mic or a calibrated UMIK-1 mic changed the sound a little and I don't deny that the curve may have been flattened, but in all cases involving DSPs built into full-range amps, critical listening has shown that the top end loses some of its sparkle / goosebump factor. And this despite the DSP not adjusting frequencies over 500K. The trouble is that the entire full-range signal has to endure this signal processor whether the top end is adjusted or not.

This finding was not just my own opinion but all visitors with an interest in music commented the same. With high quality speakers, DSP built into full-range amps has always adversely affected the important top end. This is the part that doesn't need correction as it's not significantly affected by room anomalies, but it can't avoid the circuit in this type of system. I'm all in favour of bass-only correction provided it is separated from the upper frequencies before the DSP is applied, leaving the rest of the frequency range un-DSP'd. So OK in fully active or hybrid speakers such as ML and AG.

PS - I don't use analogue sources, but I presume those who do, do so because they value their analogue signal and don't want it digitised and processed time and again.
 
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That would be throwing the baby out with the bath water, ditching the analogue source ! :eek:
But wouldn't my last paragraph above mean that the analogue baby should remain safely in the bath and clean as a whistle? ;)
 
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In fact I've used Dirac Live (in my current NAD amp), RoomPerfect (in a Lyngdorf amp), MARS (in a Micromega amp) Anthem (in the bass amp of Martin Logan speakers) and XD (in my Avantgarde speakers bass amps). I owned all of these apart from the home demo Lyngdorf.

The only ones I'd consider using are those built into bass amps - Anthem in Martin Logan and XD in Avantgarde, as the top end is sent un-DSP'd directly to the mid and top speakers.

My numerous filters taken after either the supplied mic or a calibrated UMIK-1 mic changed the sound a little and I don't deny that the curve may have been flattened, but in all cases involving DSPs built into full-range amps, critical listening has shown that the top end loses some of its sparkle / goosebump factor. And this despite the DSP not adjusting frequencies over 500K. The trouble is that the entire full-range signal has to endure this signal processor whether the top end is adjusted or not.

This finding was not just my own opinion but all visitors with an interest in music commented the same. With high quality speakers, DSP built into full-range amps has always adversely affected the important top end. This is the part that doesn't need correction as it's not significantly affected by room anomalies, but it can't avoid the circuit in this type of system. I'm all in favour of bass-only correction provided it is separated from the upper frequencies before the DSP is applied, leaving the rest of the frequency range un-DSP'd. So OK in fully active or hybrid speakers such as ML and AG.

PS - I don't use analogue sources, but I presume those who do, do so because they value their analogue signal and don't want it digitised and processed time and again.

For some reason many members here believe that DSP = Room Correction. I was speaking of DSP for implementing digital crossovers for instance or format conversions. Room Correction is a separate discussion on its own and should be addressed as “Digital Room Correction” and not as “DSP”.
 

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