Budget Directiva Project

[Rick Sykora]

Well, it is not a Purifi, but the new Dayton SIG180 looks promising. The motor structure is definitely more comparable to its competitors than the older Reference Series. I also have some the the Esoteric Series around though and they were solid performers but are no longer available. The SIG180's outer diameter is slightly larger than the Purifi, so will not simply drop in. Will have to break out the router and cut a new baffle before I can measure it. In comparison to the Wavecor, the spider is considerably stiffer and likely accounts for the SIG180's much higher resonant frequency.

More to come…

 

[D!sco]

maeby a fast/waw with full rage like alpair 5 or chp50, cheap coaxial like cx120 or omni cx 3.1...plus a 8 woofer..

XRK has this covered very comprehensively. One seems very easy (and tempting) to build.

10F/8424 & RS225-8 FAST / WAW Ref Monitor

Some sound clips of this speaker recorded with my phone and powered by my SuSyLu 100w Class A amp: Test of SuSyLu 100W Class A Amp - YouTube Example of speaker in dark “espresso brown” stain and satin lacquer with Duratex coated baffle. Example of beautiful build by as8912: Another Example...

www.diyaudio.com

And a very comprehensive but complicated build. Both sacrifice the top octave.

A Bookshelf Multi-Way Point-Source Horn

This originally started in this thread which asks the question "why aren't we building a bookshelf synergy monitor" and answers it with "we are" or at least "let's try and see what we get." I got inspired back in the Trynergy thread to build a semi bookshelf point source horn The results with...

www.diyaudio.com

And his professional projects have decent chops, so his fun projects have credibility: https://www.diyaudio.com/community/threads/lsa-signature-80-speaker.383959/

 

[Rick Sykora]

Here is my find of the day. Rather than route a new baffle, only needed to expand the outer bevel about 2mm for the SIG180 to fit the cutout for the Purifi. The most a typical rabbeting router bit will cut is about 12mm. Here is the dremel jig I used…

Using my cordless dremel as a micro router with the straight edge jig, neatly trimmed 2mm from the circumference of the woofer recess. Using this approach allowed me to keep the same center to center distance to the tweeter and the screw holes from the Purifi woofer.

 

[Trdat]

Rick, I am not sure if a system exists and I do know you make a real effort in keeping us updated but it seems its very easy to lose where we are up to in amongst all the desicion making as the thread continues. Can you update the first post with edits letting us know changes or desicions made? Or let
us know what is your preferred method so we keep an eye out according. I know its easy enough to follow the thread but sometimes you take a nap and the thread is up to 77 pages. Lol!

 

[Rick Sykora]

Rick, I am not sure if a system exists and I do know you make a real effort in keeping us updated but it seems its very easy to lose where we are up to in amongst all the desicion making as the thread continues. Can you update the first post with edits letting us know changes or desicions made? Or let
us know what is your preferred method so we keep an eye out according. I know its easy enough to follow the thread but sometimes you take a nap and the thread is up to 77 pages. Lol!

I will do a build thread eventually that should be cleaner and maybe that is what you really would like. Unfortunately, I cannot control the posts that others make. As stated, I am currently evaluating the set of woofers I have in the order posted earlier. So have fitted the SiG180 into the r1 cabinet and plan to measure it over the weekend.

Otherwise, if I am mistaken, you may need to be more specific about what you want. Editing my previous posts will only slow me down so keep that in mind. You can expect the project to follow a conventional path.

Currently the project is in the planing stage. So hope this helps!

 

[Trdat]

Otherwise, if I am mistaken, you may need to be more specific about what you want. Editing my previous posts will only slow me down so keep that in mind. You can expect the project to follow a conventional path.

I am keen to know once the design is decided, are the cabinets going to be an available flat pack that exists or have to be made as part of the DIY routed, cut and made and all? Any chance of CAD file to get them CNC'ed?

I suppose if there isn't any flat packs available for our driver choices we have to DIY the whole cabinet I am just asking as I think you mentioned that a simple flat pack would be preferable. Anyway, just curious where we are up to with this...?

And of course I don't want to slow you down so I will keep up with the thread, I just thought there might be a simple way but there isnt, no problem at all.

 

[Rick Sykora]

I am keen to know once the design is decided, are the cabinets going to be an available flat pack that exists or have to be made as part of the DIY routed, cut and made and all? Any chance of CAD file to get them CNC'ed?

Yes, but flat-pack may take some time as need to find another supplier. CAD files would be part of getting a pre-cut baffle made.

I suppose if there isn't any flat packs available for our driver choices we have to DIY the whole cabinet I am just asking as I think you mentioned that a simple flat pack would be preferable. Anyway, just curious where we are up to with this...?

Tbd as, until cabinet design/designs are finalized, not much point in engaging a vendor. There are plenty here so main concern would be getting a good price. Have not discussed with Parts Express yet so may find they have plans too.

 

[ernperkins]

I stopped following the original Directiva project when they decided on the Purifi driver, but this thread has my attention. Will be interesting to see what you think of the SIG-180. Dayton Audio does provide a distortion graph for it. They (unfortunately) don't specify the test conditions, but it may alert you to look at specific areas. I do have a couple of alternative drivers to suggest, but will wait to see what you find.

 

[Wolf]

I did some brief testing of the SIG180 in plans for my Hancocks build for the Versabox saga. My measurements were considerably different than spec.

Build Precursor, "Hancocks"...

This will be another VersaBox build, using the SIG180-4 and AMTHR-4.

diy.midwestaudio.club

Ignore first set as I left the films on the magnets by accident. However, my Qms were still 9.8 and 10.5, considerably different.

 

[Rick Sykora]

I did some brief testing of the SIG180 in plans for my Hancocks build for the Versabox saga. My measurements were considerably different than spec.

Build Precursor, "Hancocks"...

This will be another VersaBox build, using the SIG180-4 and AMTHR-4.

diy.midwestaudio.club

Ignore first set as I left the films on the magnets by accident. However, my Qms were still 9.8 and 10.5, considerably different.

Thanks. was not going to run by DATS, but now think I will!

 

[Rick Sykora]

Here is a quick and dirty measurement of the SIG180 in the Directiva r1 chassis. Measurement is gated at 1m...

This is with an untuned SB passive radiator and the f3 looks to be about 68 Hz. Good to see no nasty ringing until well beyond where the crossover will take effect.

 

[Wolf]

My HD plots would be valid, but how I did the FR is not really that viable. Even so, the average response of yours and mine are very close.

 

[617]

Here is a quick and dirty measurement of the SIG180 in the Directiva r1 chassis. Measurement is gated at 1m...

View attachment 349048

This is with an untuned SB passive radiator and the f3 looks to be about 68 Hz. Good to see no nasty ringing until well beyond where the crossover will take effect.

Quite civilized. Love these well damped drivers.

 

[Trdat]

Here is a quick and dirty measurement of the SIG180 in the Directiva r1 chassis. Measurement is gated at 1m...

This is with an untuned SB passive radiator and the f3 looks to be about 68 Hz. Good to see no nasty ringing until well beyond where the crossover will take effect.

So crossover low 2000hz...?

And were still using the SEAS DXT Tweeter? Has this been decided?

 

[Rick Sykora]

So crossover low 2000hz...?

And were still using the SEAS DXT Tweeter? Has this been decided?

For the first pass would prefer to keep the DXT tweeter. This should allow me to get the design updated faster. Will not know exact crossover frequency until am further along.

 

[Trdat]

For the first pass would prefer to keep the DXT tweeter. This should allow me to get the design updated faster. Will not know exact crossover frequency until am further along.

Great, I am really excited about this project.

Apologise for the questions just want to folow the entire process without mising a beat.

Good news about the SEAS.

 

[mcdn]

For the first pass would prefer to keep the DXT tweeter. This should allow me to get the design updated faster. Will not know exact crossover frequency until am further along.

This has to be the right approach. It’s not a cheap unit but it’s got the directivity sorted and proven. There’s no benefit for this project in trying to get similar performance with a cheaper tweeter and custom waveguide.

Even removing the PR doesn’t help cost much, except in so far as it reduced cabinet machining costs a bit.

Cheaper woofer and passive XO is all you need for a budget directiva!

 

[Rick Sykora]

Btw, my quick measurement was done without any break-in. The spider is pretty stiff so will redo after exercising the driver a bit. Was reminded of this as I unboxed the other woofer and ran DATs on it. The fS was significantly higher than the Dayton spec. Am off to help my son with house projects so may not get back on this until tomorrow.

 

[Rick Sykora]

Not much progress today as my wife was home and good measurements are more problematic. I did spend some time exercising the SiG180. This made a slight fS improvement but still a 10 Hz higher than claimed. My TSP results are almost identical to @Wolf’s.

 

[Rick Sykora]

Did chat with Part Express today and the knock-down cabinet for Directiva r1 is changing supplier, however replacement will be available in March.

Also asked about precut baffles through them and MOQ starts at 1000. Sure we can find some shops with lower requirements. Am continuing to investigate.