Does DSP belong in State of the Art Systems?
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my speakers use a first order crossover and are time and phase aligned including my bass towers. in my system i can align the bass towers and passive towers to my listening position. but that's not always practical with smaller rooms.
completely agree that at certain price points dsp does move things higher. the trade-offs are favorable. but it's not the only way.
i have no doubt that's true at particular levels of dac performance. horses for courses.
but my opinion is that at the highest level of dac performance that is not true. it can't keep up with that level of transparency.
never tried to use the Trinnov with 2 channel. it's definitely heavy handed and designed for Home Theater object based multi-channel. for movies it is unsurpassed. i do know serious Trinnov users who would disagree with you.
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Being half deaf and almost blind is a blessing in these discussions, and i always have a F.Toole quote from Francisco to fall back onLagonda, if your reading skills is like your hearing skills (avatar) Tool´s work is best left alone.
Measuring and reading other peoples responses to audio equipment is almost as good as hearing it myself I can't comment your speakers, but I would say that any loudspeaker with a passive crossover can be upgraded by an active one. How much will clearly vary.
Time alignment with passive are normally done with physical distances between drivers. However, that leads to diffraction issues, which can be very audible.
Or the typical slanting backward design leads to a higher degree of specular energy from the ceiling. Which even in a room with some broadband ceiling absorption in a AB test we did was very audible. Prototype design below.
Signal alignment with delay is simply a better tool. It does the job without any compromises And with most drivers, if not all, going from a first order crossover to a steeper one with linear phase with result in lower driver distortion.
Removal of the passive components, generally leads to purer signal path with lower distortion besides better dynamics. Many who have removed the passive crossover and replaced it with an active, have had the experience of the "washing of the window" with a higher resoloution. And there are other benefits to active as well.
I should add here that Trinnov is offering an upgrade of the DAC now and that might bring it to become "inaudible".
No !Maybe time for another hobby, "enhanced" pipe smoking perhaps, to suspend your beliefs?
I am not giving up the hobby ! My solution is to buy bigger speakers ! Easier to see in the room, and feeling the bass waves somewhat substitutes not hearing them !In a purely two channel system where the Altitude performs either straightforward preamp functionality, or, also acts as an active crossover, performance is very (very) good.
It’s not quite as good as an upper end MSB (Premier) or VTL (7.5 II), but it’s pretty close - I’ve had all of those in my signal chain with various speakers and amps. When used as a digital crossover augmented with light basic PEQ I found the net gains made for a better result than either a Premier/VTL alone or in combination.
If I could find someone uber-competent I’d mod the Altitude and suspect the performance could be improved materially.
it seems you are quite absolute in your views. there is only one case for you. always this or always that. and maybe you are right.
my room is purpose acoustically designed and built. that was 18 years ago. i spent 10 years working with the room to optimize it passively. certainly it's not perfect, no room is. but it's really good. my speakers were essentially designed for my room. and they work well. i'm happy.
dsp is answering a question i'm not asking. and i've yet to have a sense that i need to.
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The bottom line boils down to, that no matter how good a listening room one have, the speakers itself will not have an even FR. At least not one that can't be improved with EQ. On top of that, run the speakers active and harvest the benefit from that also. The end result will surely better the non-EQ/non-active version. And that is not an opinion, but a fact.
What I mentioned are can be backed up by theory and measurements.
I work with acoustics, so I know very well the importance of the room. But it doesn't change weaknesses in the speaker design. Diffraction from cabinets are basically like early arriving specular reflections from the room. But they are worse, because they arrive earlier. No treatment of the room can remedy this.
A young Micro casually browsing his personal bible by F. Toole !
In fact, I only bought the F. Toole book after reading about it in the very early days of WBF. By that time I was not young anymore!
but you cannot measure musical refinement and flow.
numbers are a small aspect of the result.
i spent 9 months treating every wall surface. i know what that did. adding dsp to improve the count of angels on heads of pins is not productive. unless the signal path quality is not at risk. again; price point relevant. but nothing absolute.
Cabinet diffraction from the speaker cabinet isn't a good thing. It brings harshness, frequency deviations and skews the imaging. It's actually very detrimental to what you describe as musical refinement and flow.
Seems like you're now discussing "room correction". That's wasn't what I was making points about. I was referring to improving the speaker design with active crossover/DSP. I don't believe in room correction. The description itself is mysleading, since you can't EQ the room. One can only correct the speaker and make a speaker fit a room better, which is something entirely different. The only way to correct a room is with physical acoustic treatment.
Typical auto correction systems which corrects the response of room brings in a lot of aberrations. The reason is what I've mentioned before; it correct's what non minium phase behaviour and that doesn't work well. That's adding phase distortion and sounds very unatural to us.
But DSP isn't the same as "room correction". As previously mentioned, just swappting the passive crossover with an active and copying the same settings would be a use of DSP. Most people here have been debating "room correction" instead of DSP and that's unfortunate because it brings confusion.
Bjorn
As someone who has just experienced what acourate can do for a pretty well setup system I think the line between room correction and dsp crossovers is pretty vague especially when measured in the room
It corrected for a room dip plus correlated right and left speakers.. quite minor adjustments for the latter.. plus it may have smoothed out crossover a bit .. its hard to know when its in room
The result exceeded my expectations.. esp in the detailed phantom image .. clearly the program has some very smart software to remove enough "room effect" to keep it from being destructive in the calcs . Uli says he uses a breakthrough phycoacoustic method
I have a clio measrement system and lspcad software program and can design an accurate dsp crossover but I could never achieve this.
Like others I would find it hard to believe it would not improve even the most fastidious room and speaker design in an all digital system .. analogue is another story
Phil
Yes. If you measure the speakers in the listening positiont it can be difficult knowing what is the response of the speaker and what is the room. One can use gating of course, but using a lot of gating will leave out a majority of the response and resolution is lost. This is why we measure speakers anechoic.
Many speakers have a deviation in the response between the left and right speaker due to driver variations. This can some cases be of several dBs in certain areas. It's a great example of where DSP could solve this, making the left and right speaker measure indentical. Something a passive crossover can't do.
I wouldn't argue that correcting for certain room anomalies can make an improvement, especially low frequency peaks. But it's a compromise compared to dealing it with physical treatment. But I think in most cases when one is running an auto correction and experience an overall improvement, it's because one is correcting the speaker. If we look at how most speakers measure, it's very evident that they can be improved considerably by DSP.
The best correction software out there, is based on frequency dependent windows (FDW), for both frequency and time domain. What does this mean? Lets take an example with an impulse response window of 10 cycles (FDW of 10). A full cycle at 20 hz takes 50 ms, so at 10 cycles the time window (gating) is open for 500 ms (0,5 sec). Sound travel at 340 m/s. so the sound at 20 hz, will travel 170 meters in the room before the measurement window shuts. That should be enough time to capture an entire room. At 1000 hz with 10 cycles the sound will travel 3,4 meters before the window is shut. (1 ms x 34 cm x 10). At 10.000 hz the sound will travel 34 cm before the window shuts. See a pattern here? So the point is, that at low frequency we have long time windows, relative to high frequencies. What does the mean, well at low fr the correction works as what we refer to room correction, or we could say that we adjust the speakers low end bass below Schroeder (below 200 hz) to the room. As we move up through the rooms transition frequency (above 500 hz) less and less of the room impact is corrected for. Above a certain frequency the EQ will be all speaker EQ. This will of cause vary with the number of cycles FDW, was set at. So by changing FDW cycles at different frequencies, we can control how much room information we want to correct for and where to only correct the speaker, pretty neat.
For some audiophiles the subjective sonic detriment to running a full-range signal through DSP easily could outweigh the theoretical benefit of an objectively even frequency response.
Having heard many such systems in the past and even owning one now I would say that your view is too absolutist because you ignore the impact of the specific system on sound quality through the distortion it introduces.
My own all active system uses separate outboard DACs to combat the inferior implementation in nearly all of these DSP correction systems. Then I get something approaching my very fine sounding passive system.
We hear frequencies (surprise) so why would anyone not want an even FR. Granted if people are used to hear a skewed FR, it will take some time to adjust to the new norm. And it is possible to get DSP, or a soundcard running from a laptop, that is sonic transparent.
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