Please review the site Rules, Terms of Service, and Privacy Policy at your convenience. Rules, TOS, Privacy
Get familiar with the reaction system: Introducing the Reaction System

Purveyor; a dynamite small 3-way with concussive tendencies....

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:

  • 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.

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.

Place all into blender and pulse 3 times....







I included the sim as I've not taken a final impedance plot yet and it should be very close.

Thanks for looking...

Steve_LeejhollanderBillet6thplanetsquamishdroc

Comments

  • Xover points were 650/5k, not as pictured in the last sim-snap.
    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.

  • Cool. Thanks for sharing.

  • I was hoping you would drop the particulars on these and you did not disappoint.

    Thanks for another interesting design, Wolf!

    :)

  • One of a few small scale speakers that sounded well above average at the InDIYana meet. Nice job Ben!

  • Thank you!

    I did have some practice. I built the Xenoliths awhile back in the same box volume using the DC160S/W3-315E/XT25SC50, but they just didn't dig all that deeply. The F3 was closer to 60Hz, and the xover HAD to be mounted on the backs externally. It was a good result as far as builds go, but I feel the Purveyor are both better and more of a success.

    6thplanetBillet
  • Those heavy SLS woofers are one of my favorites and a fantastic woofer in my novice mind. I use them crudely in table top radios and the 6” always shocks people.

    Highly interested in building this design Wolf, great alternative to many other designs including sound bars and bose systems, most likely way better than budget 5.1’s in small spaces.

  • Glad you like what you see, JB! I'm enjoying them. They are not as good as the Attitudes, but that is to be expected with a box 1/4 the volume.

  • These were good sounding fun little speakers.

Sign In or Register to comment.