Build a DIY Speaker for a fraction of the cost of Commercial Designs?

[haraldo]

Thers's some issues using the Behringer Ultradrive as an x-over in a music system..... and that's the issue of volume control

If you employ the digital inputs you need
a) a volume control in the digital domain before the Behringer, not a simple thing to do as you may lose resolution here, not all streaming players have this function too
b) You can use a multichannel analog volume control after the Behringer, most likely you'll then end up with a full av receiver with tons of functions you don't need if it's solely for music

If you employ the analog input of the Behringer you will have:
a) DAC => Preamp => ADC => DAC or (last two conversions inside the Behringer Ultradrive)
a) DAC with Preamp => ADC => DAC (last two conversions inside the Behringer Ultradrive)
I would like as few of these conversions as possible as any conversion may or will imply losses, they may be big or small but still some losses...

So the use of the Behringer is a bit tricky.... any good suggestion here Gentlemen?

 

[jinjuku]

Signal processing is much more involved then a digital volume control and bit depth definitely plays a role in the results. Theoretical differences versus what the listener practically hears is a topic of long standing debate.

Check out:
Second-Order Digital Filters Done Right

Using digital input to a DSP based crossover definitely eliminates the extra A/D->D/A. In the case of the MiniDSP and my experience with Analog Devices BlackFin DSP, the results just do not sound as good to my ears as a well implemented analog crossover. I'm not sure what to attribute that to, maybe it has to do with IIR phase characteristics. FIR would be better but the delay may not be OK depending on the number of taps needed. Digital is a funny thing, I can clearly notice a difference between different input types on the same ESS9018 based DAC.

Maybe a DCX2496 would change my mind?

I've heard systems both active and passive sound awesome. Which way one goes is all about the individual goals. For a die hard DIY'er I think an active setup with 6-8 channels of line and amp level is needed.

My upcoming project is going to be a wave guide loaded Dayton RS28F, RS180's in an MTM with transmission line cabinet. I hope to have it final by November. Going to try to have an Active and Passive version available.

 

[jinjuku]

So the use of the Behringer is a bit tricky.... any good suggestion here Gentlemen?

You have to use the Behringer in the realm it was designed for: Pro-Audio. So you need to run a pro-audio mastering interface. This in turn is driven by a computer via ASIO. Outputting over AES/EBU. I find having a computer solves all my source and streaming problems and no stepped digital attenuation problems.

 

[GranteedEV]

Signal processing is much more involved then a digital volume control and bit depth definitely plays a role in the results. Theoretical differences versus what the listener practically hears is a topic of long standing debate.

Check out:
Second-Order Digital Filters Done Right

Using digital input to a DSP based crossover definitely eliminates the extra A/D->D/A. In the case of the MiniDSP and my experience with Analog Devices BlackFin DSP, the results just do not sound as good to my ears as a well implemented analog crossover. I'm not sure what to attribute that to, maybe it has to do with IIR phase characteristics.

Actually... I would consider the possibility that the issue is in the analog circuitry of the minidsp..................

 

[haraldo]

I had a good read about minidsp platform and I'm shocked to the center of my spine.... this is really good stuff at a price that is breathtaking
The OpenDRC platform is really wow.... and the best is the price

 

[lsiberian]

Maybe a DCX2496 would change my mind?

I don't see it as a viable option. The minidsp works because of form factor and price. At the very least it can be used to get a preliminary design for the passive.

 

[lsiberian]

I had a good read about minidsp platform and I'm shocked to the center of my spine.... this is really good stuff at a price that is breathtaking
The OpenDRC platform is really wow.... and the best is the price

It's versatile for sure, but I'm not sure the price is breathtaking. It is really on par with what I would expect.

 

[Joel Foust]

Joel Foust, I have the Loudspeaker Design Cookbook, and numerous bookmarked internet sites for information. What other resources would you recommend to continue my education?

Loudspeaker design cookbook and D'Appolito's Testing Loudspeakers are good printed resources. Get involved with the DIY community, I've learned more from peers than anywhere; I still have much to learn too. When you feel ready, get a speaker design suite like SoundEasy and start playing around and model some ideas. You can simulate an entire design in SoundEasy without ever cutting a cabinet.

The SoundEasy users guide is 500 pages of material that will help you learn many design concepts. If that's a bit long, musicanddesign.com sells a SoundEasy tutorial that is condensed and provides a couple design walk throughs.

 

[Joel Foust]

I've heard systems both active and passive sound awesome. Which way one goes is all about the individual goals. For a die hard DIY'er I think an active setup with 6-8 channels of line and amp level is needed.

My upcoming project is going to be a wave guide loaded Dayton RS28F, RS180's in an MTM with transmission line cabinet. I hope to have it final by November. Going to try to have an Active and Passive version available.

My reference loudspeakers, the Linkwitz Orions, are fully active but use an analog signal processor (ASP). I'm modest enough to admit that none of my passive or DSP DIY speaker designs have urged me to move the Orion's from my main listening room.

 

[haraldo]

You have to use the Behringer in the realm it was designed for: Pro-Audio. So you need to run a pro-audio mastering interface. This in turn is driven by a computer via ASIO. Outputting over AES/EBU. I find having a computer solves all my source and streaming problems and no stepped digital attenuation problems.

Can you provide examples that work well?
In your case, what are you employing?

 

[slipperybidness]

Loudspeaker design cookbook and D'Appolito's Testing Loudspeakers are good printed resources. Get involved with the DIY community, I've learned more from peers than anywhere; I still have much to learn too.

I like the AudioXpress mag. It is speakers, amps, pres, tubes, etc.
audioXpress Magazine | AudioAmateur

 

[jinjuku]

Can you provide examples that work well?
In your case, what are you employing?

EMU 1212M {AES/EBU} <aes-ebu> <aes ebu="">Behringer DCX 2496<xlr> {XLR}Amplification (This I've done)

EMU 1212M routed through
{PatchMix}X-over routed through {PatchMix}
PEQ<adat> {ADAT} <adat>Behringer ADA 8000 preamp {XLR} <xlr> Amplification</xlr></adat></adat></patchmix></patchmix></xlr></aes>. This you could do. Good for subs for example.</aes-ebu>

 

[jinjuku]

Youtube is a great place to learn about RC / RCL filters, phase, phase angle, slew, damping etc... The math will get heavy and then it's on to Kahn Academy.

 

[slipperybidness]

Youtube is a great place to learn about RC / RCL filters, phase, phase angle, slew, damping etc... The math will get heavy and then it's on to Kahn Academy.

I have had several people, professors, bosses recommend Kahn Academy, so I will give it another +1.

Luckily for me, I have been doing that math since high school, so I am comfortable in applying it to these concepts.

 

[TheWarrior]

Loudspeaker design cookbook and D'Appolito's Testing Loudspeakers are good printed resources. Get involved with the DIY community, I've learned more from peers than anywhere; I still have much to learn too. When you feel ready, get a speaker design suite like SoundEasy and start playing around and model some ideas. You can simulate an entire design in SoundEasy without ever cutting a cabinet.

The SoundEasy users guide is 500 pages of material that will help you learn many design concepts. If that's a bit long, musicanddesign.com sells a SoundEasy tutorial that is condensed and provides a couple design walk throughs.

Totally need to pick up D'Appolito's book as I am most interested in his work with Seas.

Soundeasy looks fantastic, but I am mac user which seems to be a problem. Any other suggestions?

 

[haraldo]

Soundeasy looks fantastic, but I am mac user which seems to be a problem. Any other suggestions?

Why don't you install windows on a virtual machine on your mac?

 

[jinjuku]

Totally need to pick up D'Appolito's book as I am most interested in his work with Seas.

Soundeasy looks fantastic, but I am mac user which seems to be a problem. Any other suggestions?

Get VMWare Fusion or Parallels for Mac and then install the free 90 day evaluation of Windows 7. Less than a $100 bucks all in. When the 90 day eval expires. Reinstall. Or find a used copy of XP Pro out there.

 

[BoredSysAdmin]

Get VMWare Fusion or Parallels for Mac and then install the free 90 day evaluation of Windows 7. Less than a $100 bucks all in. When the 90 day eval expires. Reinstall. Or find a used copy of XP Pro out there.

Free https://www.virtualbox.org/wiki/Downloads is also will do the trick, but not as feature rich as other hypervisiors mentioned.

 

[jinjuku]

I like VirtualBox and I personally use it. But for the cost of VMWare Fusion the included 1 year support is REALLY a big selling point for the uninitiated.

 

[TheWarrior]

You mean I have to give Microsoft money?