Is anyone using a ULN8 as an active crossover ?

[twist222]

I currently use a DEQX HDP-3 to as an active crossover, for speaker correction and for room correction. Now whilst I am not about to give up my DEQX I am tempted to try a different way of getting there.

For anyone not familiar with the DEQX you are probably best off visiting there web site http://www.deqx.com/aboutdeqx.php But in summary the DEQX can work as a 3 way electronic crossover, apply digital correction to each of the individual drivers to correct for frequency, level, phase and time align the drivers. These corrections are based on actual speaker measurements (the measurements should be as close to anechoic as practical). Once these corrections are applied the corrected speakers are then measured in room and adjustments made (using parametric eq's) to the in room frequency response of the corrected speaker.

All the corrections and measurements are done with a computer connected to the DEQX. Once the correction filters are calculated on the PC the correction filters and room corrections are downloaded to the onboard DSP's in the DEQX.

Sorry if the above sounds like a sales pitch for the DEQX but I do like the way DEQX works.

My current music path is G5 powermac, Amarra, DAC2 (as aes/ebu interface), DEQX, 6 Nuforce V2Ref 9 SE's to ??? still finishing some DIY 3 way speakers using RAAL ribbon tweeters, PHL mids and 12 inch Peerless woofers all in sealed enclosures. Separate TM and bass enclosures.

 

BUT I have been looking at the Metric Halo ULN8 or Sonic Studios model 305 (seems to be the same as the Amarra model 4 but with the mic pre's which I would need for speaker and room measurements).

The hardware side of the ULN8 is what I would I would love to see the in the DEQX. Firewire input, 8 analogue and digital 24/192 channels available both in and out and numerous plugins available for a bit of fun (when you have nothing else to do) and you can record your vinyl to hard disk as well etc. etc lots of options with the ULN8/305.

Yes every-time I look at that hardware I keep getting that upgrade itch.

But I am not so sure about the software side ? I know Metric Halo has SpectraFoo which looks like a great measuring tool. I have seen much less information about its use as a crossover and for correction ? Sonic Studio seems to have a good parametric EQ plugin but I am looking for more than jut a good EQ plugin. I expect they do more ?

I have seen a few windows based programs designed for crossover duties but the ULN8 is Mac only. Many existing programs also run on the host computer. Yes, if it works well, but it would be nice to be able to download correction filters onto the DSP in the ULN8/305 and have it run stand alone as per what the DEQX already does.

Are there other software/ plugin options available that would work with the ULN8 ?

Should I look at a non Mac only hardware option or should I just stick with the DEQX ? Oh so many questions !!!

I expect I should also ask support over at Metric Halo and Sonic Studios/Amarra. I have had a few questions to

Amarra and found there support very good.

But my first preference is to ask here and see what others are doing. I am sure I can't be the first to see the possibilities of the ULN8/305.

I would love to hear from anyone who has already tried it or about to give it a go.

 

Regards Mark

 

 

[bdiament]

Hi Mark,

 

MH support (or their public list, https://mail.music.vt.edu/mailman/listinfo/mobileio ) is probably the best place to get your questions answered. There may be folks there doing exactly what you describe.

 

I'm sure something among the various parametric EQ algorithms included (e.g. MIOEQ6, MIOEQ12) will serve the purpose quite nicely. B.J.'s designs are the most transparent in my experience.

 

If you have a high quality microphone, SpectraFoo can provide complete analysis too (but it is sold separately).

 

Know also, that once set up, you don't always have to have your Mac connected as the ULN-8 can be set to run stand-alone.

 

Hope this helps.

 

Best regards,

Barry

www.soundkeeperrecordings.com

www.barrydiamentaudio.com

 

 

 

 

[twist222]

Barry

Thanks for the advice.

 

Spectrafoo looks like the goods for measurement and analysis.

I currently have an Earthworks M30 measurement microphone that I have been using with the DEQX for measurement duties. Hopefully this would be suitable to use with Spectrafoo ?

 

One area I am not so sure about is using parametric EQ's as crossovers ? I expect they will work but they seem to be a bit of a work around.

 

The software that is part of the DEQX system allows the choice of Butterworth or Linkwitz Riley (at 6, 12, 18, 24, 36+dB/octave) or Linear Phase crossovers at up to 300 dB/ octave. Most people use the linear phase crossovers.

 

I understand that using a different system is unlikely to provide similar options to the DEQX. That could be better or worse ? But it would be good to hear if anyone knows of any Mac based software/ plugins that are designed to work as crossovers.

Or perhaps there is someone out there who has tried using parametric EQ's as crossovers ?

 

 

 

 

[bdiament]

Hi Mark,

 

SpectraFoo is most definitely "the goods".

And your Earthworks mic sounds perfect for the job.

(I'm a big fan or Earthworks mics and use them for my recording work.)

 

I wouldn't say parametrics are a "work around". A parametric simply lets you choose the shape of the curve. The MIOEQ includes high pass and low pass filters within the parametric, selectable for each individual band.

 

Like any crossover, the sound (or lack thereof) of the filters will have a huge effect on what comes from the speakers. If nothing else, it is certainly worth trying, assuming you have access to a ULN-8. You may be very pleasantly surprised.

 

Best regards,

Barry

www.soundkeeperrecordings.com

www.barrydiamentaudio.com

 

 

[twist222]

Barry

 

Thanks for the tip on the different options available using the MH parametric EQ. I thought that only a peak/cut filter was available. I now see that 6 different kinds of parametric EQ are available in the +DSP package.

 

For us home audio blokes who are not used to DAW's if you have a plugin like the 12 point parametric EQ can you use multiple numbers of the plugin ? ie can I use one on each of the 6 channels for 3 way speakers ?

 

One last question, I currently use the full version of Amarra. Do you know if the volume control in Amarra will control the analogue volume in the MH ULN8 or will this only work with the SS model 4 ?

 

And if anyone else is using their computer to control an active crossover, speaker correction or room correction please feel free to chime in and let us know how you have found it.

 

I do like active speakers and for those of us who are using a computer as a source it does seem like a natural extension to have the computer involved in an active crossover, speaker correction and / or room correction.

 

Hope to hear from some others.

 

Regards

 

Mark

 

[bdiament]

Hi Mark,

 

Yes, in the MIO Console software, which comes with the ULN-8 (as well as the ULN-2 and 2882), you can instantiate as many iterations of a plug-in as your CPU and the internal dsp of the MH box can handle.

 

Not sure regarding Amarra's volume control. I use the ULN-8 to control volume.

 

Best regards,

Barry

www.soundkeeperrecordings.com

www.barrydiamentaudio.com

 

 

[twist222]

Hi Barry,

 

Using rowmate I can use my iPhone as a remote to control the volume in Amarra. With most Dacs like my DAC2 this is a software volume control. With the Amarra model 4 dac the Amarra volume control controls the hardware volume control in model 4. Being old fashioned I prefer to option to use a hardware volume control.

 

I am just not sure if the Amarra model 4 uses different firmware to achieve this or if it will also just work withe the ULN8.

 

Not a show stopper but it would be nice to have.

 

Regards

 

Mark

 

[Bob Stern]

The ULN-8 filters are minimum phase, so you don't have the alternative of a linear phase filter as in DEQX. This is because Pro audio equipment seeks to minimize latency, so they use IIR filters rather than FIR filters.

 

[Bob Stern]

If you are considering Metric Halo, you probably have a Mac. In that case, FuzzMeasure is good software for spectral analysis. (John Atkinson uses it.)

http://supermegaultragroovy.com/products/FuzzMeasure/

 

[bdiament]

Hi Mark,

 

If you have an Apple remote, try it with the ULN-8.

 

Best regards,

Barry

www.soundkeeperrecordings.com

www.barrydiamentaudio.com

 

 

[twist222]

Bob,

 

As you point out the software that comes with the ULN8 does not provide any Linear Phase crossovers. I am unsure of what the net effect on the sound will be but I suppose one option is to give it a try and find out.

 

Bob,

I have seen some FIR filters for windows based machines and from memory I believe one of them is available as a plug in that will work in Foobar. But as yet I have not seen any FIR filters available for Mac based systems (with the exception of some that may be able to be compiled to run under the Mac OS - but that is probably outside my league).

 

I am hoping that some of the other CA members who may be using either Minimum Phase or Linear Phase crossovers in their systems and could share how they have found them.

 

Now if only the people at DEQX could be convinced to sell their software to run as a plug in on the ULN8 !!

 

Regards Mark

 

[bdiament]

Hi Mark,

 

"Now if only the people at DEQX could be convinced to sell their software to run as a plug in on the ULN8 !!"

 

It is important to keep in mind it is not simply the type of filter but the overall design. (Reminds me a bit of some folks obsessing about particular chips instead of the entire design in which the chips are used.)

 

After you try the '8, you just might be asking MH to sell their software to run as a plug-in on the DEQX. ;-}

 

Then again, if you do feel that way, there would be no need.

 

Best regards,

Barry

www.soundkeeperrecordings.com

www.barrydiamentaudio.com

 

 

[twist222]

Yes that irrasistable urge to try differnt ways. Often not practical to compare apples with apples or in this case different hardware and software. I expect the answer is to concentrate the final outcome ie how it sounds and worry less about the different ways of getting there.

Of course unless I misunderstand how plugins work other AU plugins should also work with the ULN8 ?

 

Regards

Mark

 

[bdiament]

Hi Mark,

 

"...other AU plugins should also work with the ULN8 ?"

 

Actually, I'm not sure if it works that way. Unlike a typical DAW (which it is not) the ULN-8 may only use its own "plug-ins".

 

Strange to see myself type that I don't know. Well, maybe not so strange insomuch as after comparing the built-ins (part of the 80-bit Console and dsp software) to the rest in my audio toolbox, I never went back to any of the others, which to my ears, sounded "broken" by comparison.

 

Best regards,

Barry

www.soundkeeperrecordings.com

www.barrydiamentaudio.com

 

[twist222]

Looks like it might be something I need to check with Metric Halo. I would expect that no matter how many plugins come with the ULN8 somebody will always want to use a different plugin that is not part of the standard suite.

Even in my case whilst I may never venture past the stadard software one of the appeals of the ULN8 was the flexability of the system and not being tied down to proprietry software (not withstanding that it is Mac OS only)

 

[bdiament]

Hi Mark,

 

The thing is, the ULN-8 is not a DAW.

Folks that opt to use additional or other plug-ins will implement them via a DAW. In fact, there is a feature in the ULN-8 software, called Console Connect, wherein the entire MIO Console and all of its settings can be used as a plug in with the DAW of one's choice.

 

That said, most of the colleagues I've spoken with who use the ULN-8 tend (as I do) to use its own plug-ins. One other feature is its "primitives" which one can use to construct their own plug-ins and effects.

 

As far as a DAW goes, Reaper has turned out to be quite amazing sonically (one of the best sounding, i.e. most transparent apps in my experience) and it costs a tiny fraction of what many other, less transparent DAW apps cost. But that's a whole 'nother subject.

 

To be clear, if it isn't obvious, I am a very happy (an understatement) user of MH products but that is me. You may or may not hear it the same way. Much will depend on what you are looking for sonically and only you can make that call.

 

I hope you find what you're looking for. If you audition the '8, I'd be interested in what you hear.

 

Best regards,

Barry

www.soundkeeperrecordings.com

www.barrydiamentaudio.com

 

[Bob Stern]

Elaborating Barry Diamant's point about using MIO "primitives" to construct a FIR filter:

 

One of the DSP building blocks is a multi-tap delay line. You can cascade several of these to create an FIR filter. I don't know how many filter taps the DSP engine can handle.

 

Also, you would have to use some software to calculate the FIR filter coefficients from a desired frequency response curve and then manually enter each coefficient into the MIO software, which will download it to the ULN-8 hardware DSP engine.

 

[sdevino]

There are Linkwitz-Riley filters implemented in as crossovers (part of the bandsplit primitive) in the primitives. You can easily build your own custom crossover including any number of band splits etc.

 

I use my ULN8 for deriving LR, LCR, Dolby 5.1 with and without crossovers depending on the speakers I am using.

 

Steve

 

 

 

[bdiament]

Hi Steve,

 

Nice to "see" you here.

 

Best regards,

Barry

www.soundkeeperrecordings.com

www.barrydiamentaudio.com

 

 

[sdevino]

Thanks Barry. I am looking forward to learning what I can.

 

Steve

 

[twist222]

Bob,

 

Thanks for the pointer to Fuzzmeasure. I have added a bookmark to my favorites. A quick look shows that it does have capabilities to measure speaker component properties which would be most useful in trying to fine tune the DIY speakers I am currently trying to finish off for this active system.

The program does seem to be well explained with a fairly easy to use interface.

 

Regards

 

Mark

 

[twist222]

Thank you to Bob and Steve for the extra information about implementing other forms of crossover/ FIR filters with the MH software.

Sorry about the slow reply but I wanted to spend a little time trying to research primitives to better understand how it works. At this stage it looks like I will have to do some further research.

If anyone could provide any links to somewhere that may provide additional information on the use of "primitives" that would be great.

 

Regards

Mark

 

 

[sdevino]

Here is a link to all the DSP plugins which we have been referring to as primitives up to now. Unfortunately it doesn't seem to include some of the newer plugins including the band split.

 

http://www.mhsecure.com/technotes/v5MixerOverview/MIO+DSP_Plugin_Index/index.html

 

Happy Reading!

 

Steve

 

[twist222]

Steve,

 

Thanks for the link to the DSP plugins.

 

I managed to stumble across this link a few days ago. It was very useful for showing the options available for the parametric eq's. ie single channel. stereo, 6 point, 12 point, high pas, low pass, band pass, high self, low self etc.

 

As you say unfortunately it does not include band split. Still a useful link.

 

Regards

 

Mark

 

[rajupatel]

Hi, I am not a techie. nor do i understand the technical language being discussued. HOWEVER if room and speaker correction is what is needed then i would like to share my experience as below.

i am a music lover and took great pride in my earlier setup of EMM LABS CDSD SE Transport and EMM LABS DCC2 SE DAC, REVEL Ultima SALON speakers, GamuT monoblocks, Clearaudio turntable, transparent interconnects and Bi Wire cable etc. This is till I saw and heard a live performance of the Nutcracker Suite Ballet. Thereafter i played the same suite cd by Phillips- Valery Gergiev. LIFE CHANGED. My setup was representing only 5% of what i had heard live. Mind you it was very well set up.

 

I tried a lot of stuff and things to achieve better sound. BUT NO LUCK. Till i met a friend who has a very good pair of ears. He told me that there is a guy who can help to setup a custom room with electronics and speakers. He also told me that he HAS SETUP A system in a studio in Europe way long back and it can be auditioned. I did audition that and i was nothing short of a revelation. THE STUDIO WAS FULLY ACOUSTICALLY TREATED AND WE WERE LISTENING TO A HIGH END CD PLAYER PLAYING THROUGH THE STUDIO'S AMPLIFICATION AND SPEAKERS. Please read http://www.rayofsound.com/gamut.tas.html

 

I am not a technical guy, but i will try to explain certain issues which every music lover should understand. Sound below 300 Hz created the greatest anomaly in a listening environment. High frequency sound waves are comparatively easier to control or diffuse. For eg. the sound wave lengths are:

300Hz 45"

250 Hz 54"

200Hz 67"

150Hz 135"

100Hz 135" or 11'- 3"

80Hz 169" or 14'

60Hz 226" or 18'+

How in the world can bass trap 15" or 20" diameter or maybe 12" thick solve/absorb these waves. Beats me!! Unless somebody has changed the laws of Physics.

 

I have taken the plunge long time back and i am grinning ear to ear every time i play a cd/vinyl. And i am using reasonable priced interconnects/ and mediocre speaker cables and power cables.

 

I FEEL THAT EVERY AUDIOPHILE/MUSIC ENTHUSIAST SHOULD INVEST FIRST AND FOREMOST IN THE ROOM THAN ANYTHING ELSE.

 

Incidentally i have also tried and tested DEQX correction in my room and i felt the sound had lost it's life. Tried bass traps too. Nothing helped. I am now able to ENJOY music all over again. ALL THE TIME.

 

You might want to look at HOLM Acoustics too. Tried it in my room. It can do good things but still cant beat my setup. CHEERS....