Now that InDIYana 2022 is post-op, I figured I post the details to this little marvel that impressed quite a few last weekend.
The name is appropriate, as Purveyor means to "provide what is required or necessary".
Goals:
Xover points were 650/5k, not as pictured in the last sim-snap. I did not measure impedance and save it yet, so this should be close.
Xover board is 6" x 6.25". I ended up upgrading to the Cebo caps on the tweeters after the photo was taken. Much better, IMO.
Current prices:
P830945 = 36.98
PC83-4 = 12.98
DSN25F-4 = 18.98
SB15SFCR-00 = 35.70
Denovo 0.23ft^3 knock-down box = 26.98
Xovers as built: ~$115.20 each. I used the $4.00 75uF caps from ApexJr, and est a $1/resistor. The rest of the amounts are from Meniscus' website.
Total/cab comes to $247.14 including the cabinet, or $494.98; not bad for a compact 3-way! (My cost was $300 from discounts, salvaged upwound coils, used and free drivers, FWIW.) Most of the time, by the time you have xovers factored in with drivers on a 3-way, you're already in the $500+ category without even thinking about cabinets.
The name is appropriate, as Purveyor means to "provide what is required or necessary".
Goals:
- Use a 0.23ft^3 knock down cab with a 3-way. This meant very careful driver selection, and a W-T/M orientation.
- Make it easy to assemble for those with fewer tools. All but tweeters are surface mount.
- Make it more affordable compared to most 3-way designs.
- Yield great performance for the modest cost. All drivers have a magnetic shorting turn via a cap or ring.
- Make a simplistic 3-way xover that is easy to assemble and would fit in the box with all of the drivers.
- Peerless SLS 5" P830945; This is working in a 6 ltr net volume to produce F3/10 of 52/38. It also has higher sensitivity than ANY other 5.25" that can accomplish this bass extension feat. Being that, it has a lower Zmin above tuning at 150Hz of 2.3 ohms. This means the woofer lowpass coil has to be an air-core, and I was able to yield a Zmin of 2.6 ohms without speaker wires. This means it should be of a roughly stable 3 ohms by the amplifier sight, and a fairly stable 4 ohm load over all. It's a very minute area, and approaching 0 in terms of phase. Aluminum shorting ring, and long Xmax.
- To accomplish this response in a small box such as this, there is no way you can use a port and tune low enough. It is just not possible. I was able to fit the SB Acoustics SB15SFCR-00 5x8" PR on the back of the cab. This involved using a midrange chamber of specific orientation to allow the PR to fit, albeit offset in one direction horizontally. 2x 0.5" x 1/8" thick washers and a stainless steel Allen-head M6x1 bolt were used to tune the PR to roughly 20Hz.
- The Dayton Audio PC83-4 was used as the midrange. Being this is a 4 ohm driver, the xover landed at 650Hz to meld with the woofer to both keep impedance and xmax in check. Being the woofer is a 5.25", the off-axis response is really not impacted heavily. The tweeter and it landed at 5kHz, and the 83 has good enough off-axis response to make this just fine and keep the vocal range centered in the mid driver. The 83 also has a very benign breakup, likely due to its coated woven fiber cone, and it sounds fantastic. A decent xmax and copper cap keep it clean. 1 ltr sealed is all it needed, and this is a benefit here to give the woofer all the volume I could. (I used this midbass in the OSFA blue tooth speaker, and really liked its qualities. I also paired it with the following tweeter as a 2-way. I liked the results.)
- The Dayton DSN25F-4 Designer Series 1" was chosen to finish off the top 2 octaves, 5k+. Paired with the PC83-4, the acoustic offset seems to be really similar, the CTC is small, and the frame is tiny. Sensitivity is 95dB, so it is heavily padded -13dB, and is loafing with a very easy living. On axis, there is a small rise at 12kHz of about 3dB, but most won't notice it. Just above the tweeter axis about 15* or +4", the rise disappears and the response is really smooth and flat. A copper cap keeps it clean. FF damps the Fs. Possible bonus? These tweeters have been known to be slightly leaky. If yes- then the midrange is in a slightly aperiodic box. If not- it does not impact the performance. Of note; I had a bad unit and PE replaced it. They are on back-order until July currently.
Xover points were 650/5k, not as pictured in the last sim-snap. I did not measure impedance and save it yet, so this should be close.
Xover board is 6" x 6.25". I ended up upgrading to the Cebo caps on the tweeters after the photo was taken. Much better, IMO.
Current prices:
P830945 = 36.98
PC83-4 = 12.98
DSN25F-4 = 18.98
SB15SFCR-00 = 35.70
Denovo 0.23ft^3 knock-down box = 26.98
Xovers as built: ~$115.20 each. I used the $4.00 75uF caps from ApexJr, and est a $1/resistor. The rest of the amounts are from Meniscus' website.
Total/cab comes to $247.14 including the cabinet, or $494.98; not bad for a compact 3-way! (My cost was $300 from discounts, salvaged upwound coils, used and free drivers, FWIW.) Most of the time, by the time you have xovers factored in with drivers on a 3-way, you're already in the $500+ category without even thinking about cabinets.
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PurveryorSim2Final&VoicedXover.jpg62 KB · Views: 324
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PurveyorSim2_TweeterAxis_+15DegVRight_12thoctaveSmoothed.jpg67.8 KB · Views: 571
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SubtletySim1.jpg246.8 KB · Views: 609