• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Is there Interest in a dedicated DIY Speaker subsection?

ROOSKIE

Major Contributor
Joined
Feb 27, 2020
Messages
1,916
Likes
3,394
Location
Minneapolis
Hello everyone,

My name is David and I am a speakerbuilderaholic.

While there are a number of forums on the Internet for people with my affliction, most of them are cluttered up with old information and old ways of doing things.

Kimmo Saunisto has written VituixCAD, what has to be the best piece of XO/Speaker design software available to the average person.

It basically allows you to see the Spin-O-Ramma in the XO software as you design your speaker/crossover, it just requires that proper measurements be made that are pretty simple to do.

I was wondering if there was any interest in a sub DIY forum for speaker building, the proper use of VituixCAD and crossover design?

Kimmo looks like he is going to pack it in on Diyaudio with frustration over the simple view/method people take to speaker/crossover design despite the free tools he has provided for us.

Any interest?

Thank you,

David - London, Canada.

P.S. here is the speaker/XO I am working on with the 108 measurements I took with my automatic turntable for designing the XO.

View attachment 115734View attachment 115737View attachment 115738View attachment 115740View attachment 115741View attachment 115742View attachment 115743View attachment 115745View attachment 115746View attachment 115747View attachment 115748
I have not used that software.
I just downloaded it and will deff be interested in exploring it more.

I am very interested in a strong DIY community here. Let's do it.

By the way seriously nice DIY turntable and Mic apparatus. Seriously nice. wow.
 

Trdat

Addicted to Fun and Learning
Forum Donor
Joined
Sep 6, 2019
Messages
967
Likes
396
Location
Yerevan "Sydney Born"
Hey Dave,

I am also a speakerbuilderaholoic and have made many passive builds(proven designs) and now I am a fan of digital crossovers with DSP(my designs) I can't say I mastered designing a passive crossover which is disappointing but I just never felt the need for it especially after realizing that DSP does magic. In saying that I account for most variables before putting together a speaker, drivers and cabinet then use DSP to tie it all in.

I would love to learn vituixcad to help me build better active DSP speakers. If there is no crossover pardon the pun with vituixcad to digital crossovers than I can't say I would be interested in vituixcad as DSP is the future. Audiolense is automated and I am not far from understanding time domain sub windows, impulse responses and how to correct them manually, this would be my goal.

But if we are still discussing speaker DIY design concepts, drivers, QTC, distortion or anything related to designing a top speaker I would be participating whole heartedly.
 

OrionX76

Member
Joined
Nov 20, 2020
Messages
7
Likes
0
I have been learning measurement methods (REW) and simulating the results using VituixCAD. I am completely on board to add what I can to the conversation. At this point I have definitely had some success using the software but many, many questions remain. If we can approach best practices and recommendations for the community I think it would be well worth it.

... And that is a SWEET measuring set up! Prost!
 

Attachments

  • 4th order 03012021 Directivity (hor).png
    4th order 03012021 Directivity (hor).png
    62.1 KB · Views: 87
  • 4th order 03012021 Power+DI.png
    4th order 03012021 Power+DI.png
    32.2 KB · Views: 93
OP
D

DaveFred

Member
Joined
May 26, 2020
Messages
32
Likes
44
Location
Southwestern Ontario, Canada
I have been learning measurement methods (REW) and simulating the results using VituixCAD. I am completely on board to add what I can to the conversation. At this point I have definitely had some success using the software but many, many questions remain. If we can approach best practices and recommendations for the community I think it would be well worth it.

... And that is a SWEET measuring set up! Prost!

One thing I would strongly suggest is setting up for dual channel measurement.

This *cannot* be done with a USB mic.

If you use a USB mic, time of flight is not recorded and you must jump through hoops to set your drivers Z offset.

I was using REW with one of several USB mics, but now that I have ARTA and a dual channel external USB sound card with XLR mic, I will never go back to the USB mic.
 

Rick Sykora

Major Contributor
Forum Donor
Joined
Jan 14, 2020
Messages
3,518
Likes
7,028
Location
Stow, Ohio USA
While this seems like a good idea, ASR runs lean and it would take effort to find other related threads and move them. Then there is the question of what other items should have comparable status as well (amplifiers,streamers, etc.).

Perhaps a more targeted subsection like a Speaker Builds might be an easier sell. :)
 

Rick Sykora

Major Contributor
Forum Donor
Joined
Jan 14, 2020
Messages
3,518
Likes
7,028
Location
Stow, Ohio USA
One thing I would strongly suggest is setting up for dual channel measurement.

This *cannot* be done with a USB mic.

If you use a USB mic, time of flight is not recorded and you must jump through hoops to set your drivers Z offset.

I was using REW with one of several USB mics, but now that I have ARTA and a dual channel external USB sound card with XLR mic, I will never go back to the USB mic.

I recall this issue being called out in the VituixCAD docs, but just bought a new minidsp HD and found this:

https://www.minidsp.com/applications/dsp-basics/time-alignment

Still not sure about ARTA, but this clearly indicates the time alignment can be done in REW. Does not look like much work. Perhaps it is no longer an issue?
 
OP
D

DaveFred

Member
Joined
May 26, 2020
Messages
32
Likes
44
Location
Southwestern Ontario, Canada
While this seems like a good idea, ASR runs lean and it would take effort to find other related threads and move them. Then there is the question of what other items should have comparable status as well (amplifiers,streamers, etc.).

Perhaps a more targeted subsection like a Speaker Builds might be an easier sell. :)

Speaker design/building section is more or less what I would like to see.

A Clean one, without all the leftover baggage of "standard" staid outdated measurement techniques and crossover design tools.

Some methods that while they were great in their time, time has passed them on with new tools and techniques.

I would say 95%+ of North American speaker builders are using single channel USB measurements and only taking a single on axis measurement of their drivers.

A speaker design/building forum where part of the focus is breaking these steadfast North American traditions encouraging people to use new tools and retire the old ones.
 

Rick Sykora

Major Contributor
Forum Donor
Joined
Jan 14, 2020
Messages
3,518
Likes
7,028
Location
Stow, Ohio USA
Not sure about the numbers, but I do know we have this (and other threads) already...

https://www.audiosciencereview.com/...uilding-better-diy-speakers.11228/post-318933

While I can see encouraging "best practices", as long as there is innovation, regional and economic differences, there will be multiple ways to get good results. On the Directivia project team, individuals are using LspCAD, VACS, Bassbox and other tools, but we use VituixCAD as a common tool.

I am relatively new to ASR as well and agree there is room for improve the ability to find key topics. I suggest the easier solution is to get some topics pinned within the DIY Audio forum area for starters.
 

xarkkon

Active Member
Joined
May 26, 2019
Messages
228
Likes
338
would be interested in such an area! I've built 2 kits so far but have to confess i've no idea what i'm doing design-wise apart from blindly following instructions. heh.
 

Trdat

Addicted to Fun and Learning
Forum Donor
Joined
Sep 6, 2019
Messages
967
Likes
396
Location
Yerevan "Sydney Born"
I would say 95%+ of North American speaker builders are using single channel USB measurements and only taking a single on axis measurement of their drivers.

Here here, I am a culprit myself. I have built a large Horn based 15 inch speaker, sounds great cannot be more than happy but still haven't taken any off axis measurment. Would love to learn more in general.
 

tktran303

Addicted to Fun and Learning
Forum Donor
Joined
Mar 27, 2019
Messages
683
Likes
1,181
Hi Dave from Canada.

Count me in for a speaker-builder-holic forum.

I’m a kit builder for 1.5 decades including from Troels Gravesen, Dennis Murphy, John Krutke, Jim Mitchell, John Krevskovsky, Jim Holtz / Curt Campbell, Siegfried Linkwitz, Jeff Bagby.

All amazing people who’ve shared so much.

Due to Covid I was stuck in Hotel quarantine, taught myself VituixCAD, read Toole’s book, and simulated a few of my own kits in the past to verify that I know how to drive VituixCAD.

Then I simulated, built and then measured, and through iterations refined my crossover, all from within VituixCAD; DATS, a simple 2 way vented box with drivers I had on hand:
Purifi PTT 6.5 / SEAS T25CF002

Now I’m thinking about getting a Klippel NFS for design.

“What?!” I hear you say

“But it’s cheaper than a car”, I say...

Let’s get with the times and not just use DOS, or just on-axis measurements!
I’ve got the speaker building affliction bad...

Regards,
Thanh from Australia
 
Last edited:

Phorize

Major Contributor
Forum Donor
Joined
Apr 26, 2019
Messages
1,533
Likes
2,060
Location
U.K
While this seems like a good idea, ASR runs lean and it would take effort to find other related threads and move them. Then there is the question of what other items should have comparable status as well (amplifiers,streamers, etc.).

Perhaps a more targeted subsection like a Speaker Builds might be an easier sell. :)
A thread with inclusion rules for evidence based/validated designs or other resources would be useful. Basically a library. I’m not sure I need to see 00’s of pics of people’s projects-there are other communities that cater well for that. I see a thread with a lot of graphs.
 

tktran303

Addicted to Fun and Learning
Forum Donor
Joined
Mar 27, 2019
Messages
683
Likes
1,181
Btw Dave,

Kimmo pokes his head in and out of HTGuide.
A lot of very experienced speaker designers used to go there...if we don’t get any action we can migrate there...
 
Last edited:

OrionX76

Member
Joined
Nov 20, 2020
Messages
7
Likes
0
One thing I would strongly suggest is setting up for dual channel measurement.

This *cannot* be done with a USB mic.

If you use a USB mic, time of flight is not recorded and you must jump through hoops to set your drivers Z offset.

I was using REW with one of several USB mics, but now that I have ARTA and a dual channel external USB sound card with XLR mic, I will never go back to the USB mic.

I absolutely agree. I currently use the Scarlet 2i2 interface with loop back and it seems to be working well. I did have about 3 months where I wondered in the desert using a USB microphone. Some good people over at the diyaudio.com helped me out and set me on the right path. The problem that I see is that there doesn't seem to be a central collection of posts on using VituixCAD with REW (or ARTA). The forum threads that do exist are so scattered it is painful and time consuming to glean the useful information you need.

The VituixCAD software does have a PDF for setup and measurement with REW but it can be hard to follow and many questions emerge from the process. I would welcome the OP's suggestion of a dedicated thread... especially if he shares plans for that sweet turn table setup! ;-)
 

Adam_M

Member
Joined
Jul 23, 2020
Messages
45
Likes
32
One thing I would strongly suggest is setting up for dual channel measurement.

This *cannot* be done with a USB mic.

If you use a USB mic, time of flight is not recorded and you must jump through hoops to set your drivers Z offset.

I was using REW with one of several USB mics, but now that I have ARTA and a dual channel external USB sound card with XLR mic, I will never go back to the USB mic.

Jeff Bagby has a nice white paper on determining the Z offset that I can't find online in a quick search but have saved on my build computer. I've used it and it works quite well. Basically, you take 3 measurements: Raw woofer, Raw Tweeter, and W+T in parallel. You then input the driver X-Y coordinates in Jeff's spreadsheet, import the driver responses & sum the raw responses and adjust the z-offset in very, very small increments until they sum to match the W + T in parallel measurement. It's uncanny how well it works. You can repeat for additional pairs of drivers (for example, in a 3-way).

Would it be slightly faster if I had a dual channel mic? Yep. Does Jeff's method work and provide accurate results? Absolutely.
 

dwkdnvr

Senior Member
Joined
Nov 2, 2018
Messages
418
Likes
698
I'm not entirely sure there is enough traffic in the DIY section to warrant splitting out the speaker stuff into a sub-forum - there may not be much left in the remaining DIY discussion. It probably would provide a focused spot to put up some stickied threads on tutorials, designs, resources etc.

We had some good discussion on a DIY speaker effort here about a year ago before my world exploded and I had to go dark for a while. I've now moved but am still getting settled - no shop space for a while, and probably no space for additional speakers limiting the motivation to get too deep into the design discussions. I might have some mindshare for some associated/adjunct projects/discussions though.

One idea I did have at that time and which may be relevant in the context of the the 'Open Source Streamer' discussion was taking an active crossover model from VituixCad and using it to generate the biquad DSP filter configurations for the runtime platform - I believe Vituix will spit out the raw filter coeffs but not the full structure for a working config. Nothing ground-breaking here, but a nice convenience assist that makes iterative design easier.

You can extend the above to passive xover auralization too - just export the transfer function impulse responses as FIR filters and run through the same type of multi-channel setup as above - an RPi 4 outputting HDMI to an AVR would probably work just fine for this. Once again not exactly ground-breaking, but something that might make the design process more efficient. I think this would have to be accompanied by an ability to easily switch between different configs to be able to evaluate passive xover iterations/versions.
 
Top Bottom