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Improving IPL M4s

Even today, your CA0W1 use some of the very best drivers available. Why not try and improve on the original design?
 
Even today, your CA0W1 use some of the very best drivers available. Why not try and improve on the original design?

That had occured to me. The problem is that it means I lose my reference... and as we know, a new floozie can easily turn one's head!
 
Many thanks! However I have a couple of concerns with those:
1) (Sorry should have said) my max baffle width is 200. To match my bass extenders.
2) No FR curves on the PHL website.
I don't think the baffle width would be an issue, they're pretty compact. I have some data, including fr from magazine tests somewhere. Plenty of other good options of course- just thought I'd mention them given that they do have relatively high sensitivity for a small driver, along with the inevitable trade-off with bass extension.
 
I think I'm going to buy a set of SB drivers: MW16P-8 and TW29RB

My plan is to implement an LR2 crossover on a stepped or sloped (200mm wide) baffle.

These drivers were selected for this design and the logic seems sound:
https://meniscus.lightningbasehosted.com/wp-content/uploads/2016/02/Kairos-Write-up.pdf

Any comments?
Excellent drive units- I very nearly ordered a Kairos crossover or kit from Meniscus several times. The late Jeff Bagby really knew his stuff. At some point I may still get a pair of MW16Ps to try out in a pair of Munrosonic Eggs...
 
I will probably go with the SB drivers. Just waiting to hear if Meniscus can offer options without drivers. If not, I'll go it alone.

The modded IPLs sound really good in the kitchen. Initially I thought I'd overdone the BSC, but listening at a more sensible level, I think they are well balanced.
One disturbing thing is that they play one particular recording better than my main system :eek:.

Even my wife noticed the huge improvement in sound quality, with an unprompted "that sounds good". Can't do better than that, eh? :)
 
I think I'm going to buy a set of SB drivers: MW16P-8 and TW29RB

My plan is to implement an LR2 crossover on a stepped or sloped (200mm wide) baffle.

These drivers were selected for this design and the logic seems sound:
https://meniscus.lightningbasehosted.com/wp-content/uploads/2016/02/Kairos-Write-up.pdf

Any comments?
Other than the tweeter being a 4R whilst the mid woofer is 8R, no I don't see any problems.

For an acoustic LR2, I'd allow at least two octaves away from Fs, which means nothing lower than 2,500Hz for the tweeter. The mid woofer seems reasonably clean and even up to 2kHz.

Good luck with the design and build!
 
TBH I'm vacillating on the choice of bass/mid. Compounded by my severe lack of experience :(.

According to box sims the MW16P-8 doesn't work all that well in my smallish 9L box. The MW13P-8 works better in the box and has better off-axis behaviour, but I'm struggling to sort the rising response at 8KHz whilst keeping phase aligned, when using it with a low-order XO.

I would like to try to push the XO freq up to 3KHz. But this is based on hearsay that the 2 - 3K area should be avoided.

I'm also struggling to get the sims to give the right results for the Joachim Gerhard version, the Kalasan:
https://www.diyaudio.com/community/threads/sb-acoustics-satori-monitor.220330/page-23
It looks like this never made it to a kit at SB and they seem to have gone with a different design, the ARA. Which makes me suspicious that the kalasan didn't sound quite right:
https://sbacoustics.com/product/ara/

I never heard back from Meniscus on the Bagby Kairos :(.

This looks like the most convincing design, but i don't want to go with the 4 Ohm bass/mid and the box is too wide for my situation:
http://www.audioexcite.com/?page_id=4219

Looks like I'm stuck in procrastination mode!
 
For a nine-litre box and a choice of free-space or wall-mount crossover, you don't need to look further than the Ergo E-IX. Let's see if you can better it.
 
For a nine-litre box and a choice of free-space or wall-mount crossover, you don't need to look further than the Ergo E-IX. Let's see if you can better it.

I'm not quite sure how to reply to this, so I think honesty is the best policy.

I have heard the E-IXs 3 times at Wam shows. Somebody had a pair of corian CAOW1s at one of the shows, and they sounded a bit better to me (ports'n'all :eek:).
Of course there are plenty of caveats to this: rooms, systems, music, brief audition, no idea which XO etc etc. And the biggest caveat of all, things that are not immediately impressive can turn out to be best in the long term!!

I also admit to being biased against Scanspeak midwoofers after my experience with Proac R2.5 clones many years ago. Maybe it's the older carbon fibre drivers that have a characteristic dark sound? Maybe the newer paper cones sound more lively?

Sorry.
 
I take no offence; I did not know you've already heard the E-IX on more than one occasion. The one caveat I'll make about the E-IX is they need a fairly beefy amp to give their best due to very low sensitivity. The 15W Revelator is a very different sounding driver than the 18W8535-00 used in the Proac 2.5s.

I appreciate your honesty, and I appreciate the E-IXs may not be everyone's cup of tea. Good luck with your quest.
 
Still cogitating on driver selection!

I'm coming round to thinking that the 15W8530K01 might be the most suitable bass/mid, based on its clean waterfall, even response and no breakups. The only negative seems to be the raised 2nd HD... but my CA15RLYs are rather worse in this regard, and I been happy with those for 10 years.

My concern with the MW13P-8 is that it needs a notch filter for the 8K breakup and probably another to deal with the baffle step in my narrow baffle. I want to avoid complex XOs.

I like this site for comparing drivers. Easy to open 2 tabs and compare 2 drivers:
http://www.dibirama.altervista.org/...-15w-8530k00-mid-woofer-5-8-ohm-120-wmax.html
http://www.dibirama.altervista.org/...s-mw16tx-8-mid-woofer-6-5-8-ohm-120-wmax.html

Unfortunately they haven't tested the MW13.

I think I've ruled out these two based on the messy waterfalls:
http://www.dibirama.altervista.org/...-sph-145hq-mid-woofer-5-5-8-ohm-100-wmax.html
http://www.dibirama.altervista.org/...tal-5fe120-8-mid-woofer-5-8-ohm-160-wmax.html
 
Still cogitating on driver selection!

I'm coming round to thinking that the 15W8530K01 might be the most suitable bass/mid, based on its clean waterfall, even response and no breakups. The only negative seems to be the raised 2nd HD... but my CA15RLYs are rather worse in this regard, and I been happy with those for 10 years.

My concern with the MW13P-8 is that it needs a notch filter for the 8K breakup and probably another to deal with the baffle step in my narrow baffle. I want to avoid complex XOs.

I like this site for comparing drivers. Easy to open 2 tabs and compare 2 drivers:
http://www.dibirama.altervista.org/...-15w-8530k00-mid-woofer-5-8-ohm-120-wmax.html
http://www.dibirama.altervista.org/...s-mw16tx-8-mid-woofer-6-5-8-ohm-120-wmax.html

Unfortunately they haven't tested the MW13.

I think I've ruled out these two based on the messy waterfalls:
http://www.dibirama.altervista.org/...-sph-145hq-mid-woofer-5-5-8-ohm-100-wmax.html
http://www.dibirama.altervista.org/...tal-5fe120-8-mid-woofer-5-8-ohm-160-wmax.html

Troels said somewhere that the 15w-853xxxx produced the best midrange of any 5" driver he had tried, but I appreciate your comment that he says almost every new build is the best one. It does look excellent on paper though, and after lots of messing around with drivers, a linear frequency response is my number 1 priority. It's such a pain trying to hammer the frequency response into shape with loads of components.

I like Dibirama, you just have to watch out for those large, 10db divisions. My measurement of the Ciare HM500 looks a bit worse, mainly because of the divisions used, and perhaps less smoothing. I'm pretty sure that dip/peak (4 to 5 khz) is due to the distance from the basket to the cone. It's a shame the back can't be removed to make something better.

ciare-hm500-raw-frequency-response-on-baffle-png.1051402
ciare_hm500_risp.jpg


Peerless 830991 might be worth a look. I realise it's not paper, but it's supposed to produce an excellent midrange IIRC.
 
Peerless 830991 might be worth a look. I realise it's not paper, but it's supposed to produce an excellent midrange IIRC.

That's an excellent suggestion! Works really well in a 7.5L closed box and not far off the SS in terms of FR and waterfall. Price is decent, but not sure if I can find a pair in the UK.
 
No, I don’t need Revelator bass and the Rev has a little bump in the FR right in the middle of the frequency where my baffle step reinforcement takes place! The Disco trades off bass extension for efficiency. Distortion seems fairly similar.

http://www.dibirama.altervista.org/...-15w-8434g00-mid-woofer-5-8-ohm-120-wmax.html

http://www.dibirama.altervista.org/...-15w-8530k00-mid-woofer-5-8-ohm-120-wmax.html

The only negative with the Disco is the ridge of stored energy at ~7KHz. Hopefully this will be inaudible with an XO at <3KHz.

And I’m a tight arse and the Disco is cheaper :)
 
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