Just saw this. I retrofitted shorting rings to my vintage Polk drivers. Midrange and mid-bass was a noticeable improvement.
Hi, I've been using one as part of a studio monitor design I'm working on. This is flush mounted into a 16.7L cabinet 400mm high by 290mm wide.
Note the two bumps at 2.3kHz and 3kHz are cabinet resonances, they show up on the impedance measurements.
Three plots:
- Free Field response at 1m gated 3.5mS
- Distortion Free Field
- distortion Near Field
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Was about to get cutting some wood for a sig 180 bookshelf, winisd tells me that I'll hit xmax with a 41hz tuning in the suggested reflex box. That seems early to me but I could be wrong. Getting max spl of 102 which is plenty for this.
These will be for my partner's bedroom and she's opted for a typical two way with 104mm faceplate tweeter in walnut veneer. Not what I'd choose tweeter wise but I'm not the decision maker here and I'd like to use what I have on hand, and it'll sound just fine really. I'm going to see how the woofer behaves with a 2.5khz xover with an nd25fw (I love these things) , if that's not good I have plenty of others that will cross lower and fit.
These will be for my partner's bedroom and she's opted for a typical two way with 104mm faceplate tweeter in walnut veneer. Not what I'd choose tweeter wise but I'm not the decision maker here and I'd like to use what I have on hand, and it'll sound just fine really. I'm going to see how the woofer behaves with a 2.5khz xover with an nd25fw (I love these things) , if that's not good I have plenty of others that will cross lower and fit.
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It will depend on the box size and power also, so hard to know exaclty what you modelled.
Here is a model I have saved, using actual T/S measurements of one of the drivers I have on hand. 0.75 cf, tuned to 43Hz, xmax at 30 watts, anechoic SPL 102.8db.
Here is a model I have saved, using actual T/S measurements of one of the drivers I have on hand. 0.75 cf, tuned to 43Hz, xmax at 30 watts, anechoic SPL 102.8db.
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And here is a smaller (0.60cf) box tuned higher to 49Hz. F3 47Hz (F3 was 42Hz in the post above) but can take more power. Reaches xmax at 40 watts and SPL at 104.1db.
Ended up brain storming and decided on a modular speaker setup using the sig180. I'm hoping this build addresses some of the complaints I had with my last speaker. I repurposed the large box from that project and just slapped an mdf baffle on and tossed in the woofer, will port them eventually.
The imaging of my last project was not great, and I contribute that to the wide baffle with hard edges. I opted for a design that keeps the baffle widths sort of optimized for the driver size. I still wanted a 3 way speaker. Filtering will be active.
Just have the little tweeter "boxes" to make, then I veneer stuff. Gotta go get more wood glue because I let my big bottle freeze.... You can see the signs with the white powder dried glue.
The imaging of my last project was not great, and I contribute that to the wide baffle with hard edges. I opted for a design that keeps the baffle widths sort of optimized for the driver size. I still wanted a 3 way speaker. Filtering will be active.
Just have the little tweeter "boxes" to make, then I veneer stuff. Gotta go get more wood glue because I let my big bottle freeze.... You can see the signs with the white powder dried glue.
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Not sure if people track the pricing, but PE has been tweaking a LOT of their drivers over the last month or two. My guess is that they are trying to find a good equilibirium now thtat a lot of the supply chain issues are subsiding. Some of these have come down $20 to $30 if my memory is correct. I think the SIG225 was $90 or more, but for $70 it would make a sweet 8" two way with a robust tweeter in a waveguide. Current Pricing:
SIG120: $30
SIG150: $40
SIG180: $50
SIG225: $70
SIG270: $100
RS125: $45
RS150: $55
RS180: $68-70
RS225: $80-85
RS270: $100-132
I'm going on vacation and when I get back I start a new cabinet making job, but I'll try to get some more in depth data sometime with the 180 in this config, off axis would be nice to see.
This is my LP, just have two filters each on the 12" woofers to account for some room issues, and otherwise just 2nd order 300hz, 2500khz xover points. Definitely the best sounding speaker I've made but is that saying much?
This is my LP, just have two filters each on the 12" woofers to account for some room issues, and otherwise just 2nd order 300hz, 2500khz xover points. Definitely the best sounding speaker I've made but is that saying much?
Because I would like to take advantage of two 8 ohms in parallel = 4 ohms, to make best use of the voltage swing in my amplifiers.
But I did consider exactly what you propose. I'm just curious why they stay away from 8 ohm drivers - that's all.
If you worry about 1.5% K3 of the Sig180 why don't you just filter it out? (passively)
You can even switch it on/off during listening anytime making a cable long enough to your listening position!
Now the BIG AUDIO CONTEST : WHO is able to detect a difference and HOW does it sound?
And WHICH music for testing?
For those who have acute distortion phobia and need a quick solution here's the cure without costing a fortune , Klippel approved : https://www.kartesian-acoustic.com/copie-de-wom165-vhe
(link is correct but the driver name is
https://en.toutlehautparleur.com/speaker-kartesian-wom165-vms-8-ohm-164-5-mm.html
Btw - the 8836(?) from Usher Audio was also very good regarding distortion , stiff Kevlar cone and T-shaped pole piece with thick copper ring , flat response out to 4kHz (see test in Hobby Hifi magazine with B&K equipment) ... reflex alignment needs 30Ltr tuned to 30Hz .
Audio Heaven is not so far away as you might think 🙂
You can even switch it on/off during listening anytime making a cable long enough to your listening position!
Now the BIG AUDIO CONTEST : WHO is able to detect a difference and HOW does it sound?
And WHICH music for testing?
For those who have acute distortion phobia and need a quick solution here's the cure without costing a fortune , Klippel approved : https://www.kartesian-acoustic.com/copie-de-wom165-vhe
(link is correct but the driver name is
Wom165_vMS)
https://en.toutlehautparleur.com/speaker-kartesian-wom165-vms-8-ohm-164-5-mm.html
Btw - the 8836(?) from Usher Audio was also very good regarding distortion , stiff Kevlar cone and T-shaped pole piece with thick copper ring , flat response out to 4kHz (see test in Hobby Hifi magazine with B&K equipment) ... reflex alignment needs 30Ltr tuned to 30Hz .
Audio Heaven is not so far away as you might think 🙂
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