moved this from the Purifi driver thread
Brand new here, this would be my first foray into DiY speakers. I have a set of Dynaudio bookshelf speakers that have been backordered forever so I started looking through DiY options. I do quite like the Dynaudio house sound fwiw. I have basically zero experience designing speakers, but I do have a woodshop and some skill in that area. If this is enjoyable, and has a good result, the next step would be to design a 3-way to replace my front 3 HT speakers.
The goal is to upgrade my current 5.25" 2-way desktop speakers (Dynaudio Emit 10). The speakers are located in my "cloffice" which is quite small at 9 x 5.5', but opens up into my larger media room 18.5 x 16 on one of the narrow ends. Current equipment is a Denon receiver for 4.1 and an external Purifi stereo amp (VTV build). My subwoofer is the SVS 3000 Micro. The speakers are nearfield (1m) and have very little room behind them due to the size of the room (toed in, the near corner is 1" from the rear wall).
Speakers in Red -
The Purifi drivers looked pretty interesting, so I've read through all 1525 posts in the driver thread over the last 2 days 🤓. The thread and articles linked throughout were informative, as was the 2 hour interview of Lars on Erin's youtube (great video btw).
The most interesting designs to me are small form factor with passive rads similar to @kims build. After running some numbers, I think the 6.5" models will be too large for my desk, so I'm going to patiently wait for the 5.25" drivers to be released. I've been taking notes throughout this thread as to the tweeters folks have been using and the BlieSMa T25B-6s look to be pretty popular.
I need to sort out the crossover. Minidsp looks very interesting, but if I go active, I'd be short 2 amp channels.
Edit: Added a pic of the space so it's easier to see the constraints.
Brand new here, this would be my first foray into DiY speakers. I have a set of Dynaudio bookshelf speakers that have been backordered forever so I started looking through DiY options. I do quite like the Dynaudio house sound fwiw. I have basically zero experience designing speakers, but I do have a woodshop and some skill in that area. If this is enjoyable, and has a good result, the next step would be to design a 3-way to replace my front 3 HT speakers.
The goal is to upgrade my current 5.25" 2-way desktop speakers (Dynaudio Emit 10). The speakers are located in my "cloffice" which is quite small at 9 x 5.5', but opens up into my larger media room 18.5 x 16 on one of the narrow ends. Current equipment is a Denon receiver for 4.1 and an external Purifi stereo amp (VTV build). My subwoofer is the SVS 3000 Micro. The speakers are nearfield (1m) and have very little room behind them due to the size of the room (toed in, the near corner is 1" from the rear wall).
Speakers in Red -
The Purifi drivers looked pretty interesting, so I've read through all 1525 posts in the driver thread over the last 2 days 🤓. The thread and articles linked throughout were informative, as was the 2 hour interview of Lars on Erin's youtube (great video btw).
The most interesting designs to me are small form factor with passive rads similar to @kims build. After running some numbers, I think the 6.5" models will be too large for my desk, so I'm going to patiently wait for the 5.25" drivers to be released. I've been taking notes throughout this thread as to the tweeters folks have been using and the BlieSMa T25B-6s look to be pretty popular.
I need to sort out the crossover. Minidsp looks very interesting, but if I go active, I'd be short 2 amp channels.
- Subjectively do the T25B-6s sound bright? If so, are there other options to consider (i.e. RS28F-4)?
- Are they suitable for use in nearfield or are there objective characteristics I should be looking for instead?
- Should I use a waveguide for this type of setup or what would be the +/-'s of one at 1m?
- Rather than use 2x 5.25 PR (which haven't yet been announced @lrisbo maybe can confirm if they plan to produce that size?), is it sufficient to use a single 6.25" PR?
- If the rears of the speakers are that close to the wall, is it more optimal to place the rads on the sides?
Edit: Added a pic of the space so it's easier to see the constraints.
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Purifi let me know the 5.25s would be available in about a month, and the matching passive rads will follow, so once they publish the specs on the rads, I can get started designing.
I originally did once I realized the 6.5" would require a larger box than would be comfortable. Having said that, a smaller box than what I have currently (~9L) isn't a requirement, is there another advantage with 4s vs 5.25s (price not withstanding)?
Does anyone have any feedback on the tweeter questions or point me in the direction of a good read on the topic? Are some tweeters objectively better at nearfield than others? Thank you!
Edit: Genelec has an informative doc.
Edit: Genelec has an informative doc.
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Then build a proven design. The chance your first design is successful is basically zero, and it doesn't get better if you use expensive drivers.
Ralf
That's actually why I read through 1500+ posts on the Purifi thread. I'd like to model after one of those builds, albeit at a smaller scale with the 5.25" drivers. If that's a recipe for disaster, then I'd be interested in hearing what ~10l proven designs would be an upgrade to my current setup. I'd like to avoid assembling a pre-packaged kit as I'm not sure how much I'd learn with that process.
Your main problem is the current setup. Any speaker will sound bad against a wall if not specifically designed for that location. I highly doubt that you can achieve something better than what you have now, without changing the location. Your best bet is to build an in-wall speaker, see here for a good candidate, although it needs a sub: http://www.zaphaudio.com/ZA5/
Ralf
Ralf
Check out the GR-Research NX-Studio speakers. These are designed too be placed close to the wall but have a very open, airy sound. They also work quite well for nearfield listening. I built a pair for my bedroom system and am driving them with a DIY Purifi amp. They sound glorious. If these are too big for your desk, check out their LGK2s.
Definitely thinking outside the box there. Unfortunately it's a sit / stand desk, and while I don't listen to music or game while standing, I do use the speakers for video calls frequently so in-wall wouldn't be an option. I hadn't heard of Zaph Audio before though, so will bookmark it as it looks like they have some interesting designs for HT.
NX-Studios looks pretty interesting... Are they really 10" wide? The pictures on the site don't look it, but that's the listed dimension. If so I'd probably mock some up out of cardboard, that would be pushing the space limits. The height and depth are similar to what I have in place now.
Nice work on the build, the veneer looks great! I planned to do something similar on the entire speaker, but I dig the contrasting black on the front baffle.
Could I bother you for the other 2 measurements? That pic has me questioning the 10x depth listed on the GR site.
Mine are 17" tall and 16" deep. There is some flexibility in box dimensions, but the volume for the woofer has to be more-or-less the same. You may be able to reduce the volume a little by adjusting the amount of stuffing that you use.
I own a t25b. No waveguide on mine but I do have a 44mm edge radius.
The center to center spacing between your tweeter and mid really defines how far it will take to integrate. For my t25b + 3" I chose less than 1/2 wavelength spacing for the crossover frequency and driver spacing to increase the vertical directity. This was done because I am sitting close. I have the drivers 4mm apart.
This. If you can.
Check these out-
https://meniscusaudio.com/product/viva-voce-speaker-kit/
There is slight dip in the 300-500 Hz range works very well on a desktop.
I built a pair for the wifes computer and the sound great.
https://meniscusaudio.com/product/viva-voce-speaker-kit/
There is slight dip in the 300-500 Hz range works very well on a desktop.
I built a pair for the wifes computer and the sound great.
These could work in a sealed config.
I also found the Bagby Continuum II design on Meniscus which is intended to be placed near a wall.
That he's looking at Purity drivers and considering the desktop placement nearfield listening, would the
PTT6.5M08-NFA-01 6.5" Ultra Low Distortion Midrange- 8 ohm
https://www.madisoundspeakerstore.c...a-01-6.5-ultra-low-distortion-midrange-8-ohm/
91db fs 57Hz be able to go low enough to work in a 2-way (monitor) with an equally high-end tweeter such as the:
Satori TW29BN-B-8 Beryllium Dome Tweeter
https://www.madisoundspeakerstore.c...ers/satori-tw29bn-b-8-beryllium-dome-tweeter/
or
Mundorf AMT19CM1.1-C Air Motion Tweeter (AMT)?
https://www.madisoundspeakerstore.c.../mundorf-amt19cm1.1-c-air-motion-tweeter-amt/
PTT6.5M08-NFA-01 6.5" Ultra Low Distortion Midrange- 8 ohm
https://www.madisoundspeakerstore.c...a-01-6.5-ultra-low-distortion-midrange-8-ohm/
91db fs 57Hz be able to go low enough to work in a 2-way (monitor) with an equally high-end tweeter such as the:
Satori TW29BN-B-8 Beryllium Dome Tweeter
https://www.madisoundspeakerstore.c...ers/satori-tw29bn-b-8-beryllium-dome-tweeter/
or
Mundorf AMT19CM1.1-C Air Motion Tweeter (AMT)?
https://www.madisoundspeakerstore.c.../mundorf-amt19cm1.1-c-air-motion-tweeter-amt/