Hmmm, looks interesting, I'll investigate more thoroughly when I get home from work.
Linear phase is the main feature not available in MiniDSP's lineup. That's sufficient to keep me using a PC crossover.
It's been a while since I checked the balanced kit thread but depending on MiniDSP's spec you might or might not find better op amps in an audio interface. Same for the DACs. I haven't seen distortion and noise data for MiniDSP kits, but few audio interfaces are that well characterized either. It's unlikely there are significant differences but in the price range you're looking at the audio interface may be better. In the warped phase space the Motu Ultralite's the primary competitor to MiniDSP.
The Focusrite Saffire 24 and 40 are good starting points for interfaces to support a linear phase PC crossover.
MiniDSP is a stand-alone product; does not need a computer to function, apart from programming. If you're going to use it as an I/O card for a computer, then I agree that external sound cards become the competition.
What about ringing in linear phase vs. minimum phase?
My reason for using MiniDSP, is that I found it really hard to get at PC based crossover to function seemlessly, unless you dedicate at PC for that task. I also think it would be possible to make phase correct speaker output, with a DSP filter, and some software on the PC (Acourate or the likes).
I must admint i read about minimum phase and linear phase with great interest, but it will take some years until I have the time to really investigate this area.
I'm also a follower, not a pioneer (today it requiers a engineering diploma/ph.d., and I'm just a finance guy 🙂 ), so I wait until someone have a more or less out of the box solution.
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Very capable, There are two threads in this forum onit, Geddes has made some very good comments about it being the first measurement package has has switched too in 20 years but the author has disappeared so I doubt there will be upgrades to it in the future.
Its a great measurement tool though, easy to setup and use. Very accurate. HOLM and ARTA (Free Demo Mode) are a perfect combo in the windows world.
MiniDSP boards are equivalent to an audio interface operating standalone. One could keep, say, a Motu Ultralite tethered to the PC after programming its EQ but I'm not sure why one would want to.
Depends on the implementation and how it's used. I have only anecdotal data, but in my experience it's not much of an issue with Thuneau Frequency Allocator or Refined Audometrics PLParEQX. cuibono reported preringing problems with Waves LinEQ in the Violet DSP thread. I use Allocator and am mostly able to use the laptop for other things while it's running the crossover though using Adobe Acrobat or significant disk activity tends to knock the audio stream offline. Helps to have a VST host like Bidule where you can just double click the on/off button to bring the stream back.
Oh... I didn't put any pictures of the 15" sub.... I didn't think it was noteworthy because I didn't built it myself. 🙂
For now, I'm simply reusing my home theater sub. Its the slightly older version of this one from Paradigm.
DSP-3400 - Welcome to the New Official Paradigm® Website.
Eventually, maybe my wife would let my build some the massive array of 15" or 18" dipole subs... but probably not in our existing house. 🙄
Yeah.. Linear phase and better filters could be one of the biggest improvements over my existing setup. This would keep me moving toward the Computer based setup as optimal and most flexible solution. Maybe an outboard soundcard like the Profire2626 would provide better OpAmps and DACs?
I'm not an expert at this level of investigation so I would appreciate insights or more details on what you are running.
I read StigErik's tread with great interest but a $20k DAC + $1k software probably isn't going to happen anytime soon for me. But I have lots of PCs kicking around. 😛
Some interesting reading about FIR filters.
http://www.acoustics.hut.fi/~mak/PUB/AES124-000056.pdf
A commercial speaker using FIR filters, where ringing can be seen on the graphs (audible or not).
Stereophile: Cabasse La Sphère powered loudspeaker
http://www.acoustics.hut.fi/~mak/PUB/AES124-000056.pdf
A commercial speaker using FIR filters, where ringing can be seen on the graphs (audible or not).
Stereophile: Cabasse La Sphère powered loudspeaker
I've been reading a bunch about these computer interfaces. There are just soo many options out there that all seem like they would work quite well.
MOTU 828mKII (Great feature set, nice looking interface, software)
Presonus (ClassA preamps)
Focusrite ("known for the preamps")
M-audio (looks comprehensive)
But I'm thinking the quality of the preamp is perhaps most important? All of the manufactures think their pre-amp is great. I just don't feel like spending a bunch of money to find out for myself. Can someone help me?
With regard to the Saffire Pro, do you know if we can use the EQ plugin in standalone mode on the outputs or would it have to stay plugged into the computer??
Perhaps the biggest question. Will any of these pre-amps sound substantially better than the preamps in my DCX2496?
thanks for any advise
Josh
And probably easy to modify to better opamps (and capasitors) Like LME 49710 or dual 49720.
LME49710 - High Performance, High Fidelity Audio Operational Amplifier
LME49720 - Dual High Performance, High Fidelity Audio Operational Amplifier
With the high output and low output impedance of many sources a passive preamp is enough.
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For most folks the main audio playback flows are digital from the PC or SPDIF from a CD player, in which case mic preamp or line ADC aren't relevant. I've seen a lot of discussion about modding Behringers but have not seen before or after measurements, layout pics, or information on the components. Makes it difficult to reason about the performance tradeoffs, particularly as most audio interfaces aren't well characterized either. Basic loopback data on the Saffire 40 is here---I should go back and check the THD but as I recall it was negligible. Board on the 40's well done and the CS4272 codecs are good chips. The NJM 2122s on the mic inputs and NJM 4565s elsewhere are decent but unexceptional. Modding to 49722s or 49720s is an option but is low priority for me---moving source, crossover, EQ, and preamp functionality to digital eliminates most op amps in the signal chain so I'm content to leave the stock Saffire outs for the time being and focus on other projects.
As of this writing Focusrite's VSTs run PC side. The 24 DSP supports some onboard processing which could be handy for phono EQ but lacks the resources to operate a crossover. If I didn't have a requirement for linear phase I'd probably be using a Motu Ultralite.
In my experience pro audio's DC coupled so likely no caps.
As of this writing Focusrite's VSTs run PC side. The 24 DSP supports some onboard processing which could be handy for phono EQ but lacks the resources to operate a crossover. If I didn't have a requirement for linear phase I'd probably be using a Motu Ultralite.
In my experience pro audio's DC coupled so likely no caps.
Interesting paper; thanks for the link. I'm not aware of any rigorous comparisons but my anecdotal experience is the current ranking for performance and ease of use in linear phase options is---from best to worst---time reversed IIR, FFT, and FIR.
Thanks for the options and reminding me...I know that does not help you but now Im considering the MOTU 828mKII USB (mini notebook, Thuneau allocator/XO software) choice for my next project to replace my DCXs.
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I should have said, "MOTU 828mKIII" and FIREWIRE. But for our type of processing D/A, probably the lag time of the USB type isn't a problem.
I don't have personal experience yet, but I would remind you of twest820's comments.
I would really like to get to the bottom of this and if someone can help me ensure I am understanding this correctly I would appreciate it:
- Motu828mKIII and traveller etc can do onboard EQ without PC attached but it would be phase warping.
- Both Motu and Focusrite (and others) can be configured to do what we need (ie. EQs, shelving filters etc) but this would need to occur PC side using VST plugins in order for this solution to be linear phase. But this solution must maintain PC in the loop for processing.
Between these 2 choices, my understanding is that _maybe_ Focusrite gear has better pre-amps but in the sub $1000 range they may all be very similar.
If you would be so kind, I have a couple more questions that I hope are not to ignorant:
- I can appreciate we don't care about the ADC processes but aren't the same DAC and preamp used for the DA conversion and output circuit? 😕
- Couldn't the Motu be used just like the Focusrite interface? Just need to use the proper non-phase warping VSTs?
- Your comments seem to indicate but I would like to confirm; Are the provided Focusrite EQ VST's the non-warping linear phase type?
And finally, can you provide a subjective opinions on the sound quality of Focusrite + PC + VST solution compared to DCX solution? It seems you have had both?
The Focusrite gear definitely seems like a great price/performance and if the VSTs are good, it could be a winner for me.
Thank you very very much for your insights.
Josh
If I had the guts to do it, I would. But I would not know where to begin to undertake that kind of modification. 😱
/Josh
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