Grant and Dave
Despite the technical prowess of the Dirac software, I am not yet sold on leaving any DSP in my system all the time, and still find that an all analogue speaker crossover can let more dynamic range through.
but...
I did have a ha ha! moment while Grant was playing with the Dirac and we were switching it on and off on the fly on my speakers.
What a wonderful tool for crossover design! Being able to play "what if" and hearing the difference before replacing components to tweak the analogue crossover is really useful. It would be straightforward to arrive by trial and error to a target curve for specific drivers, room, listening position, and taste. Then one can use this target curve as the reference to aim for when voicing the passive - or active - crossover for tone. This would have saved me so much time...
The tonal changes available are infinite and pretty obvious to hear. I think we will have a good time playing with this at our get together.
Many thanks again Grant.
Despite the technical prowess of the Dirac software, I am not yet sold on leaving any DSP in my system all the time, and still find that an all analogue speaker crossover can let more dynamic range through.
but...
I did have a ha ha! moment while Grant was playing with the Dirac and we were switching it on and off on the fly on my speakers.
What a wonderful tool for crossover design! Being able to play "what if" and hearing the difference before replacing components to tweak the analogue crossover is really useful. It would be straightforward to arrive by trial and error to a target curve for specific drivers, room, listening position, and taste. Then one can use this target curve as the reference to aim for when voicing the passive - or active - crossover for tone. This would have saved me so much time...
The tonal changes available are infinite and pretty obvious to hear. I think we will have a good time playing with this at our get together.
Many thanks again Grant.
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Pierre. An active processor like a Behringer processor would be more suited for setting up xovers since they let you choose xover points, phase, delay, type of xover, gain, etc. Your aha with quick prototyping is REALLY on the money though. It could be just a normal day with the system though
. Dave. It would be neat to set up on your system because you already know the sound of it which would give you an idea if you really do like Dirac or not. It's basically a Windows like driver though so I only use it for streaming. Pierre would have liked to have hooked up the turntable. I don't know what kind of signal quality I'd get with a USB to RCA dongle or what option other people use to hook up RCA plugs.
Pierre laughed when I walked in with the desktop, keyboard, mouse, 25 inch monitor. He was expecting me to show up with a laptop. It was a fun night.
Grant.
The ability to play CDs would be nice
I should have written above "crossover voicing" instead of "crossover design". Xover points, etc., are all manageable using REW, common sense and standard measurements. Getting a flat response on axis is tedious but again, manageable. The challenging next step is tweaking this response to taste at the listening spot(s). This is where the Dirac comes in and shine IMO.
For example... Jim Smith recommends trying a modest hump (0.25 to 0.5 dB) an octave wide centered on 256 Hz. Easy to try on the Dirac. Same for baffle step compensation, top end EQ, etc. And I liked the "couch" measurements that blend in nine locations. Also, the Dirac interface is very intuitive. For instance it handles the two speakers individually at the same time. Below 200 Hz, it produced the best bass I ever heard in my room.
I should have written above "crossover voicing" instead of "crossover design". Xover points, etc., are all manageable using REW, common sense and standard measurements. Getting a flat response on axis is tedious but again, manageable. The challenging next step is tweaking this response to taste at the listening spot(s). This is where the Dirac comes in and shine IMO.
For example... Jim Smith recommends trying a modest hump (0.25 to 0.5 dB) an octave wide centered on 256 Hz. Easy to try on the Dirac. Same for baffle step compensation, top end EQ, etc. And I liked the "couch" measurements that blend in nine locations. Also, the Dirac interface is very intuitive. For instance it handles the two speakers individually at the same time. Below 200 Hz, it produced the best bass I ever heard in my room.
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It sure would be nice to not have to build 10 iterations in passive before settling on a design! 
I think I would use it similar to Pierre, to refine the target response, then get as close as possible in passive. I think it's OK to still leave it in for digital sources as a final clean up of non minimum phase stuff passive can't deal with. I'm especially curious to see what it can do about the floor bounce in the time domain (add a secondary delayed canceling impulse, suitable filtered in frequency?).
I think dynamic range would be OK if everything can be kept to 24 bits and eq modest (< 20 dB)
For crossover work, the Bozio ultimate equalizer concept is the way to go:
Bodzio Software
Ultimate Equalizer
It provides simultaneous optimization of both on and off axis to any target within capability of the driver layout and radiation patterns, with independent control of phase and amplitude. Trouble with deriving a target on axis alone is it subtly changes as soon as the crossover is changed, so this has a great advantage over dirac.
A couple things make it unattractive. I like the differences a high end amp and dac bring and it would be insanely expensive to use UE full time. This is why dirac is more attractive to me. Then there's the chorus of lamentations from many experienced builders frustrated with its UI.
Grant, it would be great if we could set a 2 hour session aside at the event for your UE. I think it would blow allot of us away!
I think I would use it similar to Pierre, to refine the target response, then get as close as possible in passive. I think it's OK to still leave it in for digital sources as a final clean up of non minimum phase stuff passive can't deal with. I'm especially curious to see what it can do about the floor bounce in the time domain (add a secondary delayed canceling impulse, suitable filtered in frequency?).I think dynamic range would be OK if everything can be kept to 24 bits and eq modest (< 20 dB)
For crossover work, the Bozio ultimate equalizer concept is the way to go:
Bodzio Software
Ultimate Equalizer
It provides simultaneous optimization of both on and off axis to any target within capability of the driver layout and radiation patterns, with independent control of phase and amplitude. Trouble with deriving a target on axis alone is it subtly changes as soon as the crossover is changed, so this has a great advantage over dirac.
A couple things make it unattractive. I like the differences a high end amp and dac bring and it would be insanely expensive to use UE full time. This is why dirac is more attractive to me. Then there's the chorus of lamentations from many experienced builders frustrated with its UI.
Grant, it would be great if we could set a 2 hour session aside at the event for your UE. I think it would blow allot of us away!
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"Crossover voicing..." that phrase has a wonderful musical (organ) sound to it.It sure would be nice to not have to build 10 iterations in passive before settling on a design!
So the notion is how to arrive at a suitable house curve. For sure, naive to think ruler-flat freq response has any special validity.
Let's say by twiddling the knobs of your DSP, you arrive at a good house curve for your ears. And for reasons I can't understand, you want a passive crossover rather than a wonderful Behringer DCX2496 and bi-amps. But you still can't just translate the house curve into the two-dozen elements of a passive crossover (even calculating to three decimal places) and expect it to result in the drivers and the speakers yielding the house curve at your seat.
The crossover voicing has to be done on the crossover breadboard because so many speaker and room elements interact in complex ways downstream of the crossover.
Ben
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Hi Ben.
I don't think ruler flat is the goal as much as it used to be but if you did set up the speakers that way and then started playing music through them the recording has all kinds of bumps the recording engineers put in. Plus you have different rooms (including treatments or lack of).
It's interesting to look at a system with a sine wave, then look at the same system playing music. Eq it flat at the system level. You'll likely notice "bumps" when looking at a graph of music playing. Pierre's system is interesting. It doesn't look ruler flat but has the bumps are pretty much smoothed out when music is playing. His explanation: "I like a smooth sound." This is the way it works in his room the speakers live in usually.
Add different taste in music and ears that have different abilities/ tastes and this leads to a flexible system making the most sense to me.
That being said DSP has a certain amount it can change the sound but the characteristics of the system still dictate a lot of what the final sound will be. The question becomes if not looking for ruler flat any more what should we be looking for. My car isn't blue. It doesn't help say what color the car is and it's REALLY obvious it isn't blue. Saying I like sensitivity in the 90's when listening to a home system is more useful. At concerts they want higher.
I'm very happy to spend some time listening to a good passive system though. And there are some very good passive systems.
Grant.
Q
I'm lucky. As a snobbish listener to only "serious" music, I can align by REW to a pretty flat curve and then crank up the subs some to voice the system.
But if I ever listened to pop-music AM radio, I'd have to drastically cut the bass or get headaches from the male announcers.
So my good luck is that serious music is produced with a minimum of tonal distortion and my EQ holds across pretty much all recordings and classical radio stations. Of course for late night quiet listening, I'd have to add more bass. Funny about Fletcher-Munson, I don't hear folks talk about that obvious and necessary adjustment even as they strut about as Olympic athletes of hearing.
Trying to out-guess the EQ present on other media and recordings... you need luck.
In 1967, I had a Stromberg-Carlson amp with continuously variable settings for recording cutting EQ for both slope and "turnover" point. That was before RIAA became the standard. So you develop a good ear. At least back then.
B.
A house curve is simply what you like.
I'm lucky. As a snobbish listener to only "serious" music, I can align by REW to a pretty flat curve and then crank up the subs some to voice the system.
But if I ever listened to pop-music AM radio, I'd have to drastically cut the bass or get headaches from the male announcers.
So my good luck is that serious music is produced with a minimum of tonal distortion and my EQ holds across pretty much all recordings and classical radio stations. Of course for late night quiet listening, I'd have to add more bass. Funny about Fletcher-Munson, I don't hear folks talk about that obvious and necessary adjustment even as they strut about as Olympic athletes of hearing.
Trying to out-guess the EQ present on other media and recordings... you need luck.
In 1967, I had a Stromberg-Carlson amp with continuously variable settings for recording cutting EQ for both slope and "turnover" point. That was before RIAA became the standard. So you develop a good ear. At least back then.
B.
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You've been doing this for a while so, like you say, house curve
. Gotta love toys. Best wishes.
Grant.
Absolutely inconceivable to me today how you'd ever want to develop an ambitious system without REW measurements and DSP. Invaluable at least for the EQ set-up but on an ongoing basis also for time adjustment if needed.
B.
Someday in the future, I'll be at this event!
Interested in seeing some gears and speakers.Will there be some blind tests for Dirac vs PEQ?
Hello from the West side!
Hello back West side.
I watched some videos from the B.C. get together. You guys/gals got one of the best together's around. That's one I'd like to make it to. I don't know how much the single driver scene is using DSP though ;-).
I don't know that anyone else is bringing a comparison but more and more DSP is becoming mainstream. I expect it will become easier to get comparisons in the future. For now I'm enjoying what I've set up/am still setting up.
Thanks for posting.
Grant.
Partly because of what people are comfortable with. And partly because of what they are uncomfortable with. Dave is a skilled crossover designer. But I charge big bucks to do what he does. And a heck of a lot smaller bucks to do a similar if not superior thing in the active domain.
I'll bring Dave over to the dark side eventually
Partly because of what people are comfortable with. And partly because of what they are uncomfortable with. Dave is a skilled crossover designer. But I charge big bucks to do what he does. And a heck of a lot smaller bucks to do a similar if not superior thing in the active domain.
I'll bring Dave over to the dark side eventually
Thanks for the compliment and right back at ya Mark!
For the record, I first wrote my first audio algorithms for DSP in ~ 1994 (and signal processing for optical in FPGA in 2000), so this certainly isn't a comfort level issue. I would much prefer to do all filtering in digital with multi dacs and amps but I just think high end dacs and amps sound better than multichannel budget dacs so prefer the dirac approach. Class D amps and dacs are improving fast, so this may change soon. Just in time for me to be old enough to not hear any difference at all.
Sorry Ron, I missed this. Yeah, let's discuss at the meet, or before then should I happen to get to it.