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Sjef 10th October 2019 02:01 PM

Quote:

Originally Posted by Tranquility Bass (https://www.diyaudio.com/forums/vendor-s-bazaar/264743-hi-dsp-based-multi-channel-integrated-preamp-crossover-dac-project-post5940010.html#post5940010)
I'm curious to know what happens to the phase at the listening position after you take into account the effects of the environment and room acoustics ?? Is it still linear ?

cheers

Well yes and no, off coarse room acoustics messes everything up again but that also counts for every little bit of DSP you'll apply to your system. I pay a lot of attention to room acoustics and even more to loudspeaker/room interaction because that is one of the most important things in the entire playback system IMHO. To realise that you have to start with a controlled directivity, linear amplitude and phase system. With the DEQX I can easily compare linear phase crossovers to linkwitz crossovers. Typically a 60db/oct or even 120db/oct linear phase crossover sounds more like a 6db/oct Butterworth but without the drawbacks of a 6db/oct crossover.

I'm using open baffle loudspeakers (yes they mess up the phase response in the room) and I can definitely hear a difference between crossover types in favour of linear phase crossovers. Take my woofers for instance, they are 2 15" drivers in a w-frame. This w-frame has a profound resonance at 230Hz. I have tried using it with Linkwitz crossovers of 12-24 and 48db/oct and a notch filter at 230Hz. Still, I cannot use them any higher then 100Hz. With 60db/oct linear phase crossover I can use them easily up to 150Hz before any negative influence of the resonance peak start to be noticeable. I'm using 60db/oct linear phase crossovers between mid and highs at 3.5kHz. With Linkwitz or butterworth filters it is easily noticeable in the in-room power response when I move the tweeter one cm. With the linear phase crossover, I can use my tweeters almost anywhere, even 50cm apart from the mids before it becomes annoying. I have tried the same with higher-order linkwitz but they don't sound nearly as good.

All in all I have my reason why I want to use linear phase crossovers. I know the drawbacks but to me, they are overshadowed by the benefits. I know a lot of people vote against them on theory but I have been using them for 15 years now and I have become quite fond of them. It puzzles me that DEQX made it so easy to implement them back in 2001 and even today no-one has been willing or able to do the same. I have tried it with a minidsp and rephase software but it is such a hassle and mistakes are so easily made that I cannot rely on it.

Like I said, I know very little about Audioweaver. It might just be possible, I don't know, that's why I ask. The reason I'm on the lookout for a replacement of my DEQX is because I want more user flexibity. Specially with open baffle loudspeakers I want to be able to eq and delay each output manually, that's it really. I'm not looking for room correction, having tried them all they do more wrong then right once you have a controlled loudspeaker/room interaction to begin with. I'm just looking for a plain simple linear phase crossover with an overall system eq and eq/delay on each output. I might fiddle around with allpass filter now and then but that's really it. After years of using DSP in various forms I have come to the conclusion that less is more.

Still the UP is interting to me. I only want to know how it can implement linear phase crossovers

Tranquility Bass 10th October 2019 11:37 PM

Quote:

Originally Posted by Sjef (https://www.diyaudio.com/forums/vendor-s-bazaar/264743-hi-dsp-based-multi-channel-integrated-preamp-crossover-dac-project-post5940046.html#post5940046)
Well yes and no, off coarse room acoustics messes everything up again but that also counts for every little bit of DSP you'll apply to your system. I pay a lot of attention to room acoustics and even more to loudspeaker/room interaction because that is one of the most important things in the entire playback system IMHO. To realise that you have to start with a controlled directivity, linear amplitude and phase system. With the DEQX I can easily compare linear phase crossovers to linkwitz crossovers. Typically a 60db/oct or even 120db/oct linear phase crossover sounds more like a 6db/oct Butterworth but without the drawbacks of a 6db/oct crossover.

I'm using open baffle loudspeakers (yes they mess up the phase response in the room) and I can definitely hear a difference between crossover types in favour of linear phase crossovers. Take my woofers for instance, they are 2 15" drivers in a w-frame. This w-frame has a profound resonance at 230Hz. I have tried using it with Linkwitz crossovers of 12-24 and 48db/oct and a notch filter at 230Hz. Still, I cannot use them any higher then 100Hz. With 60db/oct linear phase crossover I can use them easily up to 150Hz before any negative influence of the resonance peak start to be noticeable. I'm using 60db/oct linear phase crossovers between mid and highs at 3.5kHz. With Linkwitz or butterworth filters it is easily noticeable in the in-room power response when I move the tweeter one cm. With the linear phase crossover, I can use my tweeters almost anywhere, even 50cm apart from the mids before it becomes annoying. I have tried the same with higher-order linkwitz but they don't sound nearly as good.

All in all I have my reason why I want to use linear phase crossovers. I know the drawbacks but to me, they are overshadowed by the benefits. I know a lot of people vote against them on theory but I have been using them for 15 years now and I have become quite fond of them. It puzzles me that DEQX made it so easy to implement them back in 2001 and even today no-one has been willing or able to do the same. I have tried it with a minidsp and rephase software but it is such a hassle and mistakes are so easily made that I cannot rely on it.

Like I said, I know very little about Audioweaver. It might just be possible, I don't know, that's why I ask. The reason I'm on the lookout for a replacement of my DEQX is because I want more user flexibity. Specially with open baffle loudspeakers I want to be able to eq and delay each output manually, that's it really. I'm not looking for room correction, having tried them all they do more wrong then right once you have a controlled loudspeaker/room interaction to begin with. I'm just looking for a plain simple linear phase crossover with an overall system eq and eq/delay on each output. I might fiddle around with allpass filter now and then but that's really it. After years of using DSP in various forms I have come to the conclusion that less is more.

Still the UP is interting to me. I only want to know how it can implement linear phase crossovers

Yes and you could probably implement them using Audioweaver because of its flexibility which you don't get on a DEQX. Your argument is that you just want a simple button to push to enable them. However other people want to be able to run other software such as Dirac etc (when it becomes available for a PC which they said it would) which they will be able to do under the UP+. That's something DEQX just can't do. In fact there is a whole host of audio apps that run on a PC or MAC which can be run in tangent with the UP+ ;)

cheers

soundchaser 11th October 2019 04:11 PM

I do like the Audioweaver SW. There are certainly a lot of building blocks. I do wish that there was a way of simulating what is being designed if only as a check to see that one (OK "I") hasn't done something silly.

Tranquility Bass 11th October 2019 11:45 PM

Quote:

Originally Posted by soundchaser (https://www.diyaudio.com/forums/vendor-s-bazaar/264743-hi-dsp-based-multi-channel-integrated-preamp-crossover-dac-project-post5941194.html#post5941194)
I do like the Audioweaver SW. There are certainly a lot of building blocks. I do wish that there was a way of simulating what is being designed if only as a check to see that one (OK "I") hasn't done something silly.

Usually you can right click on a block and plot its frequency response ;)

cheers

Sjef 15th October 2019 12:08 AM

No need to tell me what the DEQX can do or not, I own one since 15 years. Please tell me how I can implement linear phase, be it FIR or LIR, crossovers without the need to take a course in creating reliable convolution filters like the Minidsp method. I allready explained why I want FIR crossovers, for one simple reason, because all theory aside it sounds better in my system. Why should I go back to non linear crossovers. Maybe I'm asking it in the wrong place here and I should be looking for it in the Audioweaver forum. I'd just like to know how the UP works, how I can make it do what I want. I also like to know how it's user interface works for instance. Is there any documentation available? Any video of it's user interface?

Tranquility Bass 15th October 2019 02:30 AM

Quote:

Originally Posted by Sjef (https://www.diyaudio.com/forums/vendor-s-bazaar/264743-hi-dsp-based-multi-channel-integrated-preamp-crossover-dac-project-post5944460.html#post5944460)
No need to tell me what the DEQX can do or not, I own one since 15 years. Please tell me how I can implement linear phase, be it FIR or LIR, crossovers without the need to take a course in creating reliable convolution filters like the Minidsp method. I allready explained why I want FIR crossovers, for one simple reason, because all theory aside it sounds better in my system. Why should I go back to non linear crossovers. Maybe I'm asking it in the wrong place here and I should be looking for it in the Audioweaver forum. I'd just like to know how the UP works, how I can make it do what I want. I also like to know how it's user interface works for instance. Is there any documentation available? Any video of it's user interface?

This software tool may help you do what you want to do and there is mention of supporting Audioweaver otherwise there is no harm requesting it on the DSP Concepts forum. The more people that request a feature the better ;)

FIR DESIGNER - Audio FIR filter design tool for speakers | Eclipse Audio

Our website is down at the moment but there is some documentation on how to upload Audioweaver designs to the Preamp.

cheers
david

FreedomJazzDance 15th December 2019 10:33 AM

This product can me amazing!

I wish the Trinnov Amethyst had a 3 way active crossover built in, instead of a 2 way... :(

FreedomJazzDance 15th December 2019 10:37 AM

Another nice idea would be a preamp with analog active crossovers built in :)

As far as I know, just a Kenwood integrated amp fro the 60's, had a 3 way active crossover built it.... amazing!

Kenwood Supreme 1 on thevintageknob.org

mickiboi007 15th December 2019 11:37 AM

Quote:

Originally Posted by FreedomJazzDance (https://www.diyaudio.com/forums/vendor-s-bazaar/264743-hi-dsp-based-multi-channel-integrated-preamp-crossover-dac-project-post6009777.html#post6009777)
This product can me amazing!

I wish the Trinnov Amethyst had a 3 way active crossover built in, instead of a 2 way... :(

Why bother wishing if the Trinov was available in a 3 way when this is already here with a 4 way?????

FreedomJazzDance 15th December 2019 12:59 PM

the amethyst have a 2 way active crossover only


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