edit July 3, 2022: please get 8ohm PRV 5MR450NDY; get the GRS PT2522-4 (open back no cup) planar tweeter, and the GRS 6PR-8 8ohm woofer (8x), per speaker.
This is a group buy for the XSD speaker crossover (XO) and tweeter waveguide discussed here. I think it’s best to keep the original thread for the technical discussion and this for the logistics of the GB. The XSD is 91dB sensitive open baffle dipole speaker with an 8x 6.5in woofer array for bass, a premium 5.25in low distortion high sensitivity midrange and a planar membrane tweeter. It is one of the best sounding speakers I have ever heard. The dynamics are staggering and the distortion is extremely low. You have to be careful how loud you play it because it’s hard to tell how loud it is based on distortion. The dipole nature of the speaker gives it a natural presence that simulates a live band very convincingly. The speaker plays all genres of music well. Especially complex orchestral symphonies and heavy metal that often challenges speakers not capable of nuance or dynamic range. I have voiced it to sound natural and engaging. The midrange level is adjustable through a simple resistor change if you like your vocal presentations more or less forward. The treble is light and airy and since the midrange handles the majority of the telephone band from 500Hz to 5000Hz, the speaker has a coherence and spatial imaging of a point source full range speaker.
The XO Kit will include all the resistor, capacitor, and induxtorcomponents plus a schematic for you to assemble the components to generate a passive XO that provides the following filters at 470Hz and 4700Hz. You will need to follow the dimensioned speaker plans (sketch) which I can provide via email if you PM your request. Note that this is a commercial design so I have been given special permission to provide the XO kits with the requirement that you do not share the schematic or post it publicly.
This is my prototype build:
Renders so you can visualize it in a lighter color scheme. I think satin piano white would be a good look as well:
Measured harmonic distortion:
Predi
Impedance is 4ohms nominal but well
I’m also providing a custom CNC’d aluminum waveguide and bezel for the GRS PTT2522-4 tweeter. It has a satin bead blasted black anodized finish. It’s more than cosmetic as it improves the bandwidth extension, lowers distortion, and smooths the output in addition to providing a nice way to mount the tweeter.
The XSD crossover BOM was developed using quality components. All Mills 12W MRA12 non inductive resistors for the mid and tweeter, and 20w non-inductive wirewound 1% Dayton resistors on the woofer shelving filter. Iron core 18ga inductor for the woofer, 18ga air core for the midrange, and 20ga aircore for the tweeter. All capacitors are MKP film (mix of Audyn Q4 and Dayton DPMC) plus one 100uF 400v bipolar electrolytic. You are welcome to upgrade the electrolytic to a film cap on your own if you choose.
The XO will consist of:
6 Mills MRA12 12W resistors
2 Dayton DPR 20W 1% non-inductive resistors
8 Audyn Q4 MKP caps for midrange and tweeter
8 Dayton DPMC MKP caps for midrange and woofer
2 100uF 400v bipolar electrolytic caps for woofer
2 20ga aircore inductors for the tweeter
4 18ga aircore inductors for the midrange
2 18ga ironcore inductors for the woofer
Here is a photo of an earlier crossover with an electrolytic bipolar cap and film cap bypass for the woofer to give you an idea of how I laid things out:
Here is photo of my prototype XO (with some optional upgrades like all film caps for the woofer section) - the quality of the parts on the Kit offered here are as equivalent otherwise and even better since you will receive all non inductive resistors like Mills MRA and the large 20W Dayton for the woofer shelving filter:
Edit Aug 14, 2022: here is a XO built by member Plott using the actual parts from this GB. Very nice work.
I am offering the XSD XO Kit (stereo pair) as group buy or $375 - majority of this is for the cost of the parts and small amount for my effort to assemble the kits. If you want the CNC waveguides, those are an additional $68/pair.
Photos of the waveguide:
This waveguide is also very handy if you want to use this tweeter in another project as it’s a superb tweeter for many applications.
You can have a listen to the speaker here (recorded with my phone):
Here is the GB interest list so far. Please add your name, qnty of XO kits and WG pairs, and country if you are interested.
Shipping is not included and will depend on your location and be auto calculated through my Etsy shop. Typically circa $15 in USA. Overseas will be higher as there 8 inductors and some large film caps plus aluminum waveguides. My guess is circa $35.
Name / #XO’s (pair) / WG’s (pair) / Country
____________________________________
Bryguy / 1 XO / 1 WG / USA
JHClark / 1 XO / 1 WG / USA
32y0 / 0 XO / 1 WG / Australia
bloqhed / 1 XO / 1 WG / USA
This is a group buy for the XSD speaker crossover (XO) and tweeter waveguide discussed here. I think it’s best to keep the original thread for the technical discussion and this for the logistics of the GB. The XSD is 91dB sensitive open baffle dipole speaker with an 8x 6.5in woofer array for bass, a premium 5.25in low distortion high sensitivity midrange and a planar membrane tweeter. It is one of the best sounding speakers I have ever heard. The dynamics are staggering and the distortion is extremely low. You have to be careful how loud you play it because it’s hard to tell how loud it is based on distortion. The dipole nature of the speaker gives it a natural presence that simulates a live band very convincingly. The speaker plays all genres of music well. Especially complex orchestral symphonies and heavy metal that often challenges speakers not capable of nuance or dynamic range. I have voiced it to sound natural and engaging. The midrange level is adjustable through a simple resistor change if you like your vocal presentations more or less forward. The treble is light and airy and since the midrange handles the majority of the telephone band from 500Hz to 5000Hz, the speaker has a coherence and spatial imaging of a point source full range speaker.
The XO Kit will include all the resistor, capacitor, and induxtorcomponents plus a schematic for you to assemble the components to generate a passive XO that provides the following filters at 470Hz and 4700Hz. You will need to follow the dimensioned speaker plans (sketch) which I can provide via email if you PM your request. Note that this is a commercial design so I have been given special permission to provide the XO kits with the requirement that you do not share the schematic or post it publicly.
This is my prototype build:
Renders so you can visualize it in a lighter color scheme. I think satin piano white would be a good look as well:
Measured harmonic distortion:
Predi
Impedance is 4ohms nominal but well
I’m also providing a custom CNC’d aluminum waveguide and bezel for the GRS PTT2522-4 tweeter. It has a satin bead blasted black anodized finish. It’s more than cosmetic as it improves the bandwidth extension, lowers distortion, and smooths the output in addition to providing a nice way to mount the tweeter.
The XSD crossover BOM was developed using quality components. All Mills 12W MRA12 non inductive resistors for the mid and tweeter, and 20w non-inductive wirewound 1% Dayton resistors on the woofer shelving filter. Iron core 18ga inductor for the woofer, 18ga air core for the midrange, and 20ga aircore for the tweeter. All capacitors are MKP film (mix of Audyn Q4 and Dayton DPMC) plus one 100uF 400v bipolar electrolytic. You are welcome to upgrade the electrolytic to a film cap on your own if you choose.
The XO will consist of:
6 Mills MRA12 12W resistors
2 Dayton DPR 20W 1% non-inductive resistors
8 Audyn Q4 MKP caps for midrange and tweeter
8 Dayton DPMC MKP caps for midrange and woofer
2 100uF 400v bipolar electrolytic caps for woofer
2 20ga aircore inductors for the tweeter
4 18ga aircore inductors for the midrange
2 18ga ironcore inductors for the woofer
Here is a photo of an earlier crossover with an electrolytic bipolar cap and film cap bypass for the woofer to give you an idea of how I laid things out:
Here is photo of my prototype XO (with some optional upgrades like all film caps for the woofer section) - the quality of the parts on the Kit offered here are as equivalent otherwise and even better since you will receive all non inductive resistors like Mills MRA and the large 20W Dayton for the woofer shelving filter:
Edit Aug 14, 2022: here is a XO built by member Plott using the actual parts from this GB. Very nice work.
I am offering the XSD XO Kit (stereo pair) as group buy or $375 - majority of this is for the cost of the parts and small amount for my effort to assemble the kits. If you want the CNC waveguides, those are an additional $68/pair.
Photos of the waveguide:
This waveguide is also very handy if you want to use this tweeter in another project as it’s a superb tweeter for many applications.
You can have a listen to the speaker here (recorded with my phone):
Here is the GB interest list so far. Please add your name, qnty of XO kits and WG pairs, and country if you are interested.
Shipping is not included and will depend on your location and be auto calculated through my Etsy shop. Typically circa $15 in USA. Overseas will be higher as there 8 inductors and some large film caps plus aluminum waveguides. My guess is circa $35.
Name / #XO’s (pair) / WG’s (pair) / Country
____________________________________
Bryguy / 1 XO / 1 WG / USA
JHClark / 1 XO / 1 WG / USA
32y0 / 0 XO / 1 WG / Australia
bloqhed / 1 XO / 1 WG / USA
Last edited:
GB Status Update
Name / #XO’s (pair) / WG’s (pair) / Country
____________________________________
Bryguy / 1 XO / 1 WG / USA
JHClark / 1 XO / 1 WG / USA
32y0 / 0 XO / 1 WG / Australia
bloqhed / 1 XO / 1 WG / USA
Dawa / 1 XO / 1 WG / Sweden
Name / #XO’s (pair) / WG’s (pair) / Country
____________________________________
Bryguy / 1 XO / 1 WG / USA
JHClark / 1 XO / 1 WG / USA
32y0 / 0 XO / 1 WG / Australia
bloqhed / 1 XO / 1 WG / USA
Dawa / 1 XO / 1 WG / Sweden
Do you know if it's possible to remove the cup from the back of the closed version? Those seem to still be in stock and add only a couple dollars more expensive
I haven’t done it myself but they appear to be held in place by an adhesive. I think a putty knife might be able to do it. I would say cut it off with a Dremel tool but that would generate particles that might get caught in the membrane and magnet.
GB Status Update
Name / #XO’s (pair) / WG’s (pair) / Country
____________________________________
Bryguy / 1 XO / 1 WG / USA
JHClark / 1 XO / 1 WG / USA
32y0 / 0 XO / 1 WG / Australia
bloqhed / 1 XO / 1 WG / USA
Dawa / 1 XO / 1 WG / Sweden
Pinnocchio / 0 XO / 1 WG / Canada
jack_b/ 1XO / 1 WG / USA
Name / #XO’s (pair) / WG’s (pair) / Country
____________________________________
Bryguy / 1 XO / 1 WG / USA
JHClark / 1 XO / 1 WG / USA
32y0 / 0 XO / 1 WG / Australia
bloqhed / 1 XO / 1 WG / USA
Dawa / 1 XO / 1 WG / Sweden
Pinnocchio / 0 XO / 1 WG / Canada
jack_b/ 1XO / 1 WG / USA
GB Status Update
Name / #XO’s (pair) / WG’s (pair) / Country
____________________________________
Bryguy / 1 XO / 1 WG / USA
JHClark / 1 XO / 1 WG / USA
32y0 / 0 XO / 1 WG / Australia
bloqhed / 1 XO / 1 WG / USA
Dawa / 1 XO / 1 WG / Sweden
Pinnocchio / 0 XO / 1 WG / Canada
jack_b/ 1XO / 1 WG / USA
veereshai/ 1XO / 1 WG / USA (NoVa)
Name / #XO’s (pair) / WG’s (pair) / Country
____________________________________
Bryguy / 1 XO / 1 WG / USA
JHClark / 1 XO / 1 WG / USA
32y0 / 0 XO / 1 WG / Australia
bloqhed / 1 XO / 1 WG / USA
Dawa / 1 XO / 1 WG / Sweden
Pinnocchio / 0 XO / 1 WG / Canada
jack_b/ 1XO / 1 WG / USA
veereshai/ 1XO / 1 WG / USA (NoVa)
XRK,
I want to augment the quantiies in my GB commitment. I now want three sets of the wave guides total - the other item is unchanged.. I look forward to your findings on alternative sources for the GRS PT2522-4.
Thank You in Advance,
JHClark
GB Status Update
Name / #XO’s (pair) / WG’s (pair) / Country
____________________________________
Bryguy / 1 XO / 1 WG / USA
JHClark / 1 XO / 3 WG / USA
32y0 / 0 XO / 1 WG / Australia
bloqhed / 1 XO / 1 WG / USA
Dawa / 1 XO / 1 WG / Sweden
Pinnocchio / 0 XO / 1 WG / Canada
jack_b/ 1XO / 1 WG / USA
veereshai/ 1XO / 1 WG / USA (NoVa)
Name / #XO’s (pair) / WG’s (pair) / Country
____________________________________
Bryguy / 1 XO / 1 WG / USA
JHClark / 1 XO / 3 WG / USA
32y0 / 0 XO / 1 WG / Australia
bloqhed / 1 XO / 1 WG / USA
Dawa / 1 XO / 1 WG / Sweden
Pinnocchio / 0 XO / 1 WG / Canada
jack_b/ 1XO / 1 WG / USA
veereshai/ 1XO / 1 WG / USA (NoVa)
Hi Folks,
I am running into supply chain issues with some of the parts. The 100uF 100v Nichicon KZ BP cap is not available. I am using the UEP series 100uF 100v bipolar and it sounds great. I’m going to have to make that substitution to this group buy. I’m also going to have to use a 47uF plus 3.3uF MKP Auddyn Q4 as 50uF MKP is almost out of stock.
I am running into supply chain issues with some of the parts. The 100uF 100v Nichicon KZ BP cap is not available. I am using the UEP series 100uF 100v bipolar and it sounds great. I’m going to have to make that substitution to this group buy. I’m also going to have to use a 47uF plus 3.3uF MKP Auddyn Q4 as 50uF MKP is almost out of stock.
The GB is moving favorably towards trigger pull time. I am building shopping carts and getting ready to place orders. I think I will do this the way I always do GBs and that’s to collect funds as pre-orders on my Etsy shop. That way, the fulfillment logistics are much simpler. Especially for shipping to the EU which is now a total nightmare for the average person with all the new regulations.
XRK,
If I independently buy two Dayton Audio DPMC-100 film capacitors and independently substitue them for the Nichicon KZ BP caps - do I gain or lose?
My Thanks in Advance,
JHClark
You can do that and I think it does improve the sound. The effect is subtle - I would describe as more resolving bass detail. That is, low level bass detail comes out more. As the distortion in the bass is so low, these things can matter.
I am now taking pre-orders for the GB in my shop. Please indicate in the list if you have placed a pre-order.
XO only or XO with Waveguide bundle:
https://www.etsy.com/listing/122418...9&ga_search_query=XSD&ref=shop_items_search_1
Waveguide only:
https://www.etsy.com/listing/122420...902&click_sum=35fb7475&ref=shop_home_active_1
XO only or XO with Waveguide bundle:
https://www.etsy.com/listing/122418...9&ga_search_query=XSD&ref=shop_items_search_1
Waveguide only:
https://www.etsy.com/listing/122420...902&click_sum=35fb7475&ref=shop_home_active_1
GB Status Update
Name / #XO’s (pair) / WG’s (pair) / Country
____________________________________
Bryguy / 1 XO / 1 WG / USA
JHClark / 1 XO / 3 WG / USA
32y0 / 0 XO / 1 WG / Australia
bloqhed / 1 XO / 1 WG / USA / Ordered
Dawa / 1 XO / 1 WG / Sweden
Pinnocchio / 0 XO / 1 WG / Canada
jack_b/ 1XO / 1 WG / USA
veereshai/ 1XO / 1 WG / USA (NoVa)
Name / #XO’s (pair) / WG’s (pair) / Country
____________________________________
Bryguy / 1 XO / 1 WG / USA
JHClark / 1 XO / 3 WG / USA
32y0 / 0 XO / 1 WG / Australia
bloqhed / 1 XO / 1 WG / USA / Ordered
Dawa / 1 XO / 1 WG / Sweden
Pinnocchio / 0 XO / 1 WG / Canada
jack_b/ 1XO / 1 WG / USA
veereshai/ 1XO / 1 WG / USA (NoVa)
JHClark has placed his order with the ETSY links aove. 23MAY at 0815 hrs Central +-.