Hi,
Shaun alerted us over at the SoundEasy users forum about this thread. I have been using the UE from it's start. My system is a stereo four way dipole. The tweeter and mid are passively crossed at 2000hz then actively crossed using UE to an upper bass driver at 500hz, and then to sub bass at 125hz. So to UE it is a three way crossover.
In my system the UE replaced a Behringer DCX 2496 crossover. With the UE imaging is rock solid and the frequency response is really smoothed out. My tweeter has some rough areas that were impossible to correct passively or with the DCX2496. It's been a great improvement.
I built an Intel i3 2100 fanless system using an M-Audio FireWire 410 out. With a stereo 3 way system the i3 barely breaks a sweat.
For music from the computer I use JRriver along with VAC. Others have had problems with VAC but is works fine for me.
Mike
Shaun alerted us over at the SoundEasy users forum about this thread. I have been using the UE from it's start. My system is a stereo four way dipole. The tweeter and mid are passively crossed at 2000hz then actively crossed using UE to an upper bass driver at 500hz, and then to sub bass at 125hz. So to UE it is a three way crossover.
In my system the UE replaced a Behringer DCX 2496 crossover. With the UE imaging is rock solid and the frequency response is really smoothed out. My tweeter has some rough areas that were impossible to correct passively or with the DCX2496. It's been a great improvement.
I built an Intel i3 2100 fanless system using an M-Audio FireWire 410 out. With a stereo 3 way system the i3 barely breaks a sweat.
For music from the computer I use JRriver along with VAC. Others have had problems with VAC but is works fine for me.
Mike
I have been studying Frequency-Warped FIR (WFIR and WIIR) filters in the literature as a method of combining frequency, time, and phase correction. There are several good papers on the Web, as well as Linux based open source C-code programs for WFIR filters. The experts have developed practical solutions to the real world problems. WFIR libraries for a few DSP ICs are mentioned on the Web.
I just started my WFIR education.
Thanks for the info Pixelpusher.
It is my experience that only about 5% of the audiophile population builds their own speakers (I am one of those).
It is my opinion, after careful research of UE and its capabilities, that the other 95% would also benefit quite a bit from the usage of this product in the following ways:
1. Smoothing and correcting in room frequency response
2. Correcting overall phase response from the music source to the listening position, which should encompass all the components such as the preamp (if the UE computer is inserted between the source and preamp), amp, speakers, various interconnects and speaker wire.
3. This can all be accomplished with basically a good mic purchase, the UE software, and a compatible computer system (my build, in a nice component-like case is around $1500).
4. It should be able to do all this through existing, or retail speakers with their crossovers being used, but with the phase correction basically correcting any deviance introduced by them or any other component in that loop.
In summary, the UE is acting like a large, global feedback loop (although off a generated algorithm instead of real time monitoring) and should provide its improvements regardless of whether it is used as an active crossover or not. If this is true, it should have a MUCH larger group of audiophiles (basically all) that could benefit from its use rather than just speaker builders. In order for those other audiophiles to see the need for this, it will need to be tested under these circumstances (using retail speakers for instance, and their crossovers) and listen tests conducted and the benefits disclosed. If this is not done, it will remain a niche product. I believe it has the capability of benefitting all audiophiles, and think the product will benefit from this much wider perspective for all of us.
It is my experience that only about 5% of the audiophile population builds their own speakers (I am one of those).
It is my opinion, after careful research of UE and its capabilities, that the other 95% would also benefit quite a bit from the usage of this product in the following ways:
1. Smoothing and correcting in room frequency response
2. Correcting overall phase response from the music source to the listening position, which should encompass all the components such as the preamp (if the UE computer is inserted between the source and preamp), amp, speakers, various interconnects and speaker wire.
3. This can all be accomplished with basically a good mic purchase, the UE software, and a compatible computer system (my build, in a nice component-like case is around $1500).
4. It should be able to do all this through existing, or retail speakers with their crossovers being used, but with the phase correction basically correcting any deviance introduced by them or any other component in that loop.
In summary, the UE is acting like a large, global feedback loop (although off a generated algorithm instead of real time monitoring) and should provide its improvements regardless of whether it is used as an active crossover or not. If this is true, it should have a MUCH larger group of audiophiles (basically all) that could benefit from its use rather than just speaker builders. In order for those other audiophiles to see the need for this, it will need to be tested under these circumstances (using retail speakers for instance, and their crossovers) and listen tests conducted and the benefits disclosed. If this is not done, it will remain a niche product. I believe it has the capability of benefitting all audiophiles, and think the product will benefit from this much wider perspective for all of us.
Phase correction
I have listened quite a bit to (non-minimum) phase correction albeit not in SE but similarly implemented on PC. Well, if you expect spectacular audio effects you might be a little dissapointed. My experience is phase has less audible sound impact than FR. But still I think it is quite worthwhile. If combined with flat FR (the other prerequisite for flat phase - this time flat FR means linear minimum phase component) it can give sometimes some discomforting feelings as the sound becomes so spatial and 3D that in some recordings there is a strange impression that e.g. sound comes from behind you or from above you ...
I have listened quite a bit to (non-minimum) phase correction albeit not in SE but similarly implemented on PC. Well, if you expect spectacular audio effects you might be a little dissapointed. My experience is phase has less audible sound impact than FR. But still I think it is quite worthwhile. If combined with flat FR (the other prerequisite for flat phase - this time flat FR means linear minimum phase component) it can give sometimes some discomforting feelings as the sound becomes so spatial and 3D that in some recordings there is a strange impression that e.g. sound comes from behind you or from above you ...
I took time today to test MP vs. LP again. The biggest difficulty is that I cannot do instantaneous switching, something that I think is necessary for detecting differences in something as subtle as phase. I have to say that I cannot detect a difference, not that it isn't there. It takes literally one minute for me to switch MP to LP and vice versa, but that alone makes it unreliable IMO.
My system is close to being physically aligned, so the crossover and phase of drivers in the crossover, used MP, provide excellent response with frequency response correction only.
It's a 3-way dipole woofer and mid with a monopole tweeter. I also pass a full range signal through the other pair for a subwoofer. Each side as 2 10" Peerless (Genelec as buyouts), a single SS 15w/4531 mid and a DXT tweeter. W/M is 250Hz LR8, M/T is 1200 LR8.
One key benefit for me was the rapidity of design/auditioning. I had an idea of what crossover would probably work best for the polar response, only to find that it was just the opposite. I was able to create and measure literally dozens of crossovers to arrive at what I'm using now. All in one evening. My goal was smooth polar response. I have no idea how long this would have taken without the UE.
Dave
There is one controversial aspect of phase correction which is to be precise non-minimumum phase correction. The only physical way it can be realised is to introduce a preresponse. And here comes a question if it is good given the fact that there is high end CD equipment where an upgrade is offered to make linear phase non-linear to get rid of a similar pre-response. The argument goes it "smears" the transients. I have brought it up on the SoundEasy forum but Bohdan Raczynski of SE for whatever reason did not like this rather interesting question.
The only thing that "smears" transients, is phase inaccuracies at one of two points, the source material, of which we audiophiles have no control over except what we choose to buy, and the sound at the listeners ears after the source material has been processed by the audio chain between the source and listeners ears.
Phase response is the measurement of time delay between different sound frequencies to a given position from the speakers. To audiophiles the only position that really matters is the listening position. Many things can induce phase differences in the frequency range we care about, 16hz to 20Khz. Some of the things that cause phase distortion are: Audio circuits in the pre-amp and main amp (tone controls are a biggie here), speaker crossovers, the drivers themselves (inductance in woofer voice coils, weight of cone, etc.), interconnects (capacitance, inductance) just to name a few.
While it is true some high end audio components go to great lengths to avoid phase problems (such as amps designed with no global feedback), what those that understand its importance try and do is match components so that the overall phase response that hits the listeners ears is correct with respect to the source material's phase response. Some may go a bit further, and design their systems so that the phase response CORRECTS there favorite source materials response. Either way, they are using their components to get it correct, and spend a large amount of money to do it (not uncommon at all for some to spend more than $10k on each component).
Phase response is easy to explain. Say you hit a snare drum with the drumstick. It produces sound at many frequencies. For this discussions sake, let's keep it simple and pretend it creates frequencies of 100hz, 1khz and 10khz all beginning at the same time. In any normal audio system, those phase problems mean that those three frequencies will NOT reach the ear at the same time. There will be delays on them, that could vary. Those delays in the sounds not reaching your ear at the same time are the "smear" in phase response, and the thing audiophiles work hard to correct. This software, UltimateEqualizer, has the potiential to eliminate this type of distortion from the point it is introduced in the system (right after the source in my planned implimentation) right up to where ever you place the mic to set it up.
In my opinion, fullfilling every audiophiles dream of eliminating on more thing that stands in the way of accurate reproduction of music in one's listening environment.
There is probably a very simple explanatin for this.
The website and forums for this product show plainly it was conceived, designed and implemented for digital active crossover use with speakers, and this definitely appears to be Bohdan's focus. Very often a designer stays focused on his creation with his intended focus as his guideline and doesn't like to distract from that.
What I believe is that his creation has a great use a little outside its intended purpose in correcting phase distortion and frequency response of any system, in addition to, or outside of its role in digital active crossovers.
So I would not give too much credence to the fact he didn't respond to your question, he was probably just staying focused on his project.
The most important issue is "what is being equalized?".
My experience is that equalizing near field measurements generate more convincing playback. Equalization of 1M measurements result in more damped sound, but the image focus is a bit smeared. I have not tried equalizing in room response, but I would expect more damped sound and more smear of image focus. For this reason, I had asked whether UE3 will allow only equalizing low passed response, and the answer was YES.
Unless I miss my guess, he's referring to the impulse response, the time domain (hence the term used, "preresponse") , not the frequency domain as you are here. His reference to linear/non-linear phase may be confusing. The way I think it should be stated is linear phase vs. minimum phase (i.e. "non-linear"). The term non-linear isn't usually used in this context.
That and the term transient response is also referring to the impulse response, not music "transients". Different context, different aspect altogether.
If what he says is correct I get the impression that there is "correction" for the "correction". The goal being linear phase and its implementation not being perfect, someone else thinks that it introduces errors that need correcting, i.e., return the output back to minimum-phase in the frequency domain so that it "corrects" the problem in the time domain.
My assumption may be wrong, but that's how I read it at the moment. More detail of the "fix" would help, but then I'm not very well versed on details of DSP.
Dave
All versions of the UE going back to the one in SoundEasy V17 EQ only what you specify. If all you do is enter a lowpass, that's what it equalizes. However, I don't believe that you could then use any of the phase linearization capability since that requires that both highpass and lowpass be specified in the target. I suppose, though, that it's possible to "unwrap" the excess-phase to the point that only the highpass phase remains. It seems to me that improving the phase response at the low end would be more beneficial given that we are more sensitive to phase at the low end.
Dave
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I guess it would be a good idea to define what I mean by phase distortion:
phase distortion or phase-frequency distortion is distortion that occurs when a filter's phase response is not linear over the frequency range of interest, that is, the phase shift introduced by a circuit or device is not directly proportional to frequency
Taken from here: Phase distortion - Wikipedia, the free encyclopedia
phase distortion or phase-frequency distortion is distortion that occurs when a filter's phase response is not linear over the frequency range of interest, that is, the phase shift introduced by a circuit or device is not directly proportional to frequency
Taken from here: Phase distortion - Wikipedia, the free encyclopedia
I think what I was addressing are separation of speaker equalization vs room equalization. Certainly want the phase to be flat, but in addition, in order to preserve the image focus, we want to be sure that what we are equalizing is not a combination response of waves with time difference exceeding one wave length.
Audiophile 192
I have a M-Audio Delta Audiophile 192 PCI card that I am using for speaker testing. Good card for that purpose because it handles 5 Volt RMS which is much better than the typical 2 Volt for most good sound cards and even some cheaper cards only go to 1 Volt which is pretty much worthless. Limitation is 4 in and 2 out. I will use my ASUS Zonar D2 PCI card to work with 4 way crossovers.
Ted
I have a M-Audio Delta Audiophile 192 PCI card that I am using for speaker testing. Good card for that purpose because it handles 5 Volt RMS which is much better than the typical 2 Volt for most good sound cards and even some cheaper cards only go to 1 Volt which is pretty much worthless. Limitation is 4 in and 2 out. I will use my ASUS Zonar D2 PCI card to work with 4 way crossovers.
Ted
Hi Ted
i read audiophile 192 has 4 out. do you mean 2 balance out? while advertised as 4 single ended out?
i need only 4 single ended out. do you think its a good choice for ultimate equalizer? i can get this sound card cheap
thanks alot for the asus zonar d2 suggestion. really appreciated. i broaden up the soundcard selection. any more suggestion? juli@?
Do you use ultimate equalizer for your 4 way crossover?
thanks
erwin
i read audiophile 192 has 4 out. do you mean 2 balance out? while advertised as 4 single ended out?
i need only 4 single ended out. do you think its a good choice for ultimate equalizer? i can get this sound card cheap
thanks alot for the asus zonar d2 suggestion. really appreciated. i broaden up the soundcard selection. any more suggestion? juli@?
Do you use ultimate equalizer for your 4 way crossover?
thanks
erwin
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