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My latest creation. A 3-way speaker using Scan-Speak Discovery 22W/8534 woofer, Eton 5-880 midrange, and Vifa XT250TG30 in a Visaton WG148R waveguide. The woofer is in a transmission line cabinet
Baffle is solid Sapele with a maple stripe. OCD may kick in with this one a bit, the boards chosen weren't a great match so there is a colour difference between the two speakers, also some natural wood features break the perfect symmetry. Hardwood is finished with Tung oil, cabinet is painted flat grey with a quality washable wall paint. I used the scraps from the driver cutouts to make some terminal cups on the back side. I still have to make some feet for these, I have plans to do something nice with the leftover sapele off-cuts.
The Scan-speak 22W/8534 woofer is excellent. Smooth response right up to 1.5kHz where it starts beaming. Larger than average cone surface area for a driver of its size.
In-cabinet response shown at 15 deg increments.
HD was tested at 3V and 30cm distance. Very little to complain about with this woofer.
The Eton 5-880 presented a bit of a challenge. It's response takes a 5-6dB steep drop at 2kHz, which limits what can be easily done with it using a passive filter, and a bit unfortunate for a small 5" driver. It is a fibreglass honeycomb cone, and this response is not that different from what you get with the Dynavox yellow honeycomb drivers as well. It's funny that the Discovery 8" woofer provides a smoother response up past 2kHz here.
In-cabinet response shown at 15 deg increments.
HD was tested at 3V and 30cm distance. Eton has a simple motor, so distortion results are not the best, but far from the worst. Cone breakup shows up as 3rd order peak at 2.2kHz.
The Vifa XT25TG30 used here is an old stock tweeter, from the pre-Tymphany days, these were "made in Denmark". Even with the waveguide, there is still some baffle diffraction showing up on-axis in the 2-3kHz range, but it's still a very usable response overall.
In-cabinet response shown at 15 deg increments.
HD was tested at 3V and 30cm distance.
Bringing it all together, I arrived at the following result. Some compromises were made to keep parts count and cost at a reasonable "mid-tier" level.
Overall it actually an excellent sounding speaker, very enjoyable sound, great kick drum punch, nothing really to complain about, just enjoyable music
Baffle is solid Sapele with a maple stripe. OCD may kick in with this one a bit, the boards chosen weren't a great match so there is a colour difference between the two speakers, also some natural wood features break the perfect symmetry. Hardwood is finished with Tung oil, cabinet is painted flat grey with a quality washable wall paint. I used the scraps from the driver cutouts to make some terminal cups on the back side. I still have to make some feet for these, I have plans to do something nice with the leftover sapele off-cuts.
The Scan-speak 22W/8534 woofer is excellent. Smooth response right up to 1.5kHz where it starts beaming. Larger than average cone surface area for a driver of its size.
In-cabinet response shown at 15 deg increments.
HD was tested at 3V and 30cm distance. Very little to complain about with this woofer.
The Eton 5-880 presented a bit of a challenge. It's response takes a 5-6dB steep drop at 2kHz, which limits what can be easily done with it using a passive filter, and a bit unfortunate for a small 5" driver. It is a fibreglass honeycomb cone, and this response is not that different from what you get with the Dynavox yellow honeycomb drivers as well. It's funny that the Discovery 8" woofer provides a smoother response up past 2kHz here.
In-cabinet response shown at 15 deg increments.
HD was tested at 3V and 30cm distance. Eton has a simple motor, so distortion results are not the best, but far from the worst. Cone breakup shows up as 3rd order peak at 2.2kHz.
The Vifa XT25TG30 used here is an old stock tweeter, from the pre-Tymphany days, these were "made in Denmark". Even with the waveguide, there is still some baffle diffraction showing up on-axis in the 2-3kHz range, but it's still a very usable response overall.
In-cabinet response shown at 15 deg increments.
HD was tested at 3V and 30cm distance.
Bringing it all together, I arrived at the following result. Some compromises were made to keep parts count and cost at a reasonable "mid-tier" level.
- The midrange high pass is just a single cap, which results in a bump in the low end response from the driver Fs. I compared to a 2nd order filter that provided a smoother filter roll-off and better phase alignment, decided it wasn't worth the effort as overall response was not really affected much at all and the Eton is capable of handling a little low frequency output without strain.
- The tweeter filter is 3rd order to match the fast cliff in the midrange response.
- The woofer filter would need some big parts to avoid the 30-40Hz dip and 80-200Hz bump, so I decided to live with it as-is.
- Rising response >10kHz will be un-noticed by most, only observable on-axis. I focus more on listening window response that single on-axis results, and listening window response is very good.
Overall it actually an excellent sounding speaker, very enjoyable sound, great kick drum punch, nothing really to complain about, just enjoyable music
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