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Droogne

A large synergy horn

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They are finished for now, with a single woofer each, and I have everything for a loner thread. However, I'm still not happy with them so I keep on tweaking and measuring etc till I'm satisfied.

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So you currently have a single 12P80Fe in each? Did you ever decide on a cd? Also do you still have your K-402's? 

I picked up a set of K-402's last year to replace my JBL 2360's with 2445J's. Ended up deciding on the Axi2050 and picking those up too. I had it narrowed to those vs the Radian 950bePB. I was set to try the Radian but it turned out to be much more expensive and with a longer lead time than the Celestion. Unfortunately I haven't gotten my shit together and made the switch yet. 

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1 minute ago, Ricci said:

So you currently have a single 12P80Fe in each? Did you ever decide on a cd? Also do you still have your K-402's? 

I picked up a set of K-402's last year to replace my JBL 2360's with 2445J's. Ended up deciding on the Axi2050 and picking those up too. I had it narrowed to those vs the Radian 950bePB. I was set to try the Radian but it turned out to be much more expensive and with a longer lead time than the Celestion. Unfortunately I haven't gotten my shit together and made the switch yet. 

I never had the K402, because they were so goddamn expensive over here in Europe. 

 

For CD I just use a JBL 2447, but I'm definetly gonna replace them. Same for the 12P80Fe. Good drivers I'm sure, but both very heavy (10+ kg each) which limits the portability. Getting the 110x80x60cm cabin down will be extremely difficult to start with, the weight will make it a lot harder to manouver them.

 

However, I would probably go for a BMS4595 (I need a 1.5" throat..). The Radian if I can find a second hand. Maybe make a 1.4 to 1.5" adapter so I can have a wider pick of drivers.

The celestion look pretty cool! A more high end version of the BMS? (or at least when looking at the price ;) ). 

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At this moment I have enourmous trouble making them sound good. They are OK, they 'work'. Inteligibillity is fine, and better than most of the speakers I have had, but not superb. At least not to compensate for their size. 

Bass is also very poor. However I should not be mad about that ;) It's because of the 12P80Fe driver. It modelled very poorly under 100hz. However, they are incredibly strong from 120-700hz (126dB; 2pi, RMS)

image.png.b05e7bb83cd510a519dbb83a58b19190.png

A port might help (firing from sides, or top when they stand vertical.), especially if I can block them of so I can keep them 'sealed' too.

image.png.39d5fb1e9160f2adbdce37959e12f109.png

Maybe I can just sacrifice part of the horn (5-10cm from the width on each side). At the sides (horizontal definetely) the horn is almost completely flat. 

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Any of you guys sufficiently experienced with REW to have a look at my measurements to see what I might be doing wrong? 

I particularily am dissatisfied about the bass part, even when EQd flat to 80hz (with subs). 

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I am dangerous enough with REW. What are you looking for or concerned with specifically? Measurements? Response? Filter simulation? Etc. 

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4 hours ago, Droogne said:

I never had the K402, because they were so goddamn expensive over here in Europe. 

 

For CD I just use a JBL 2447, but I'm definetly gonna replace them. Same for the 12P80Fe. Good drivers I'm sure, but both very heavy (10+ kg each) which limits the portability. Getting the 110x80x60cm cabin down will be extremely difficult to start with, the weight will make it a lot harder to manouver them.

 

However, I would probably go for a BMS4595 (I need a 1.5" throat..). The Radian if I can find a second hand. Maybe make a 1.4 to 1.5" adapter so I can have a wider pick of drivers.

The celestion look pretty cool! A more high end version of the BMS? (or at least when looking at the price ;) ). 

Gotcha...I thought I saw 402's in some pictures you posted. They are expensive. I bought a used pair and they were not cheap. I got quoted a new pair and it was much more. I hate to think what it would cost to get them landed over in the EU after VAT. Luckily I don't really care about looks for the warehouse system. 

I do like the weight savings of neo drivers. The 2445 JBL "tweeters" are over 30lbs. 

The Axi2050 is different from any of the other cd's out there. It's a relatively newly patented diaphragm shape. Supposedly it gets really wide bandwidth with no crossover and less breakup than normal diaphragm shapes / materials. I've heard that as usual for a 2" exit cd the air above 14 or 15kHz isn't as good as a smaller cd or a Be unit but the midrange is supposed to be very good. Also it has huge surface area and claims to be able to get down to 300Hz. 

What is slightly irritating is I contacted PE about the Axi2050 6 months ago and they said it could not be special ordered from Celestion due to it being OEM only. Now it is on their website for sale. 😒 Oh well...I still paid less for it delivered all of the way from the UK. 

What kind of help are you needing with REW? 

 

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4 hours ago, klipsch said:

I am dangerous enough with REW. What are you looking for or concerned with specifically? Measurements? Response? Filter simulation? Etc. 

Just basic stuff, I can EQ till I get a +-1dB flat response, but thats it. I dont require anything fancy for now. Can I maybe mail you the measurements, than you can maybe make some suggestions (mic setup, crossover choice and what not)? Normally I'm in contact with Chris A (if you know him), but I dont want to impose too much on him.

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Cool topic, I wonder why I haven't discovered it yet.

For speaker measurements I'd recommend doing those in a anechoic room (outside for us plebs). I think speakers with a native flat response over ~500Hz sound better than speakers which have been EQ'd flat indoors. Our brain basically filters out reflections to a degree, which the measurement mic does not. Even if you end up measuring a spike and EQ'ing that away, you might percieve it as lacking in that region then.

If you have enough amp channels/dsp channels you could go with the B&C DCX464 as alternative to the BMS. It will have higher dynamic range (111db sensitivity+almost 400W power handling?! dear god...) and probably have a wider operating range due to the dedicated mid. It's priced similarly. I'm planning on doing a build with those and possibly something like a 12NDL88 or some 10" drivers.

I'll also play around with the DE360. It won't go ultra loud but the HF response is super smooth with the new diaphragm material. Plus that one is only like 60€!

 

3 hours ago, Ricci said:

I've heard that as usual for a 2" exit cd the air above 14 or 15kHz isn't as good as a smaller cd or a Be unit but the midrange is supposed to be very good.

B&C have optimized phase plugs inside their CD's to help with that issue and if you built some into your horn throat it should help. Would probably be too much effort for a single DIY project thou and I have no clue what those would look like.

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2 hours ago, Ricci said:

Gotcha...I thought I saw 402's in some pictures you posted. They are expensive. I bought a used pair and they were not cheap. I got quoted a new pair and it was much more. I hate to think what it would cost to get them landed over in the EU after VAT. Luckily I don't really care about looks for the warehouse system. 

Yes, importing them costs around 2500-3000.. That is WITH the K69, but that doesnt compensate.The horns I have now I got for less than 500. Resale value is nihil (although they are build by Don Keele so it has a 'name'), but I didnt bother too much as I was gonna cut holes in them which slashes their value either way 🙂 .

2 hours ago, Ricci said:

I do like the weight savings of neo drivers. The 2445 JBL "tweeters" are over 30lbs. 

Yes, going to a BMS4592 would save more than 8kg (20 lbs) in weight.

Same for the woofers, I want 4 in it I should switch to P80Nd instead of the Fe version. Goes from 12.5kg to 6.5kg (so for 4 woofers thats 25kg..).

 

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7 minutes ago, peniku8 said:

Cool topic, I wonder why I haven't discovered it yet.

For speaker measurements I'd recommend doing those in a anechoic room (outside for us plebs). I think speakers with a native flat response over ~500Hz sound better than speakers which have been EQ'd flat indoors. Our brain basically filters out reflections to a degree, which the measurement mic does not. Even if you end up measuring a spike and EQ'ing that away, you might percieve it as lacking in that region then.

I know.. but I just can lug it outside. However, we will be using them for an outside event, so before it takes place I'm gonna take the chance to EQ them completely. 

What would you recommend for inside EQ (in a 'chaotic room'). Just EQ down to 500hz? 

7 minutes ago, peniku8 said:

If you have enough amp channels/dsp channels you could go with the B&C DCX464 as alternative to the BMS. It will have higher dynamic range (111db sensitivity+almost 400W power handling?! dear god...) and probably have a wider operating range due to the dedicated mid. It's priced similarly. I'm planning on doing a build with those and possibly something like a 12NDL88 or some 10" drivers.

I have thought about both of them, compared to my JBL2447. At the moment I have enough channels on the XP4080 to do a 3-way. As I have listed once on AVSf:

"The DCX464 lists as 110+80W with a 111.1dB/1W and 111.4dB/1W sensitivity respectively, measured on a "320hz" exponential horn, so ~134dB net. However, I'm not sure how this translates to my 80x40 horn.

The BMS lists as a 80+150W with a 118dB/1W sensitivity, measured on a 40x20 horn. I gather it will be around6dB lower than on my 80x40, which would fit with the 110dB/1W when looking at the graphs BMS has for the 4594. So a net of ~134.5dB.

So both show around a 134dB output at RMS. I already have JBL 2447 drivers, which are listed at around 132dB down to (at least) 700hz. So around 70% less output. Radion 950 would seems like a whopping 135.5W continues on a 80x40."

7 minutes ago, peniku8 said:

I'll also play around with the DE360. It won't go ultra loud but the HF response is super smooth with the new diaphragm material. Plus that one is only like 60€!

The DE360 only goes down to 1200hz, and my synergy stops at 700hz.

 

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Also, random idea. Use 2x 12" on side (horizontal) and 1x 21" (the 21LW1400 for which I have no purpose) on the other side. So a 3 way actually

2x12" is around 150-700hz 131-133dB at RMS Xmax limited.

The 21"' can easily do 50-150hz 131dB, with 50-80hz at 135dB. I think if I model this as a 3-way MEH, the overlap between 80 and 150hz will add a lot more, that way it will do 135dB down to at least 135hz. And go to 50hz.

As listed above, the BMS/B&C can do a theoretical 135dB at RMS. 

My 4x 12" solution (with ports, 75hz) would result in a response I'd prefer though, the 21" is just something to toy with. 4x 12" is way more powerfull (aka 135dB at RMS) up to the crossover so it can match the CD. It would only go down to 60hz if I tune it low, but with a slightly higher tune I can add some output in the 80-200hz range (which I would like to boost in general, to match the subs). 

image.png.2411163ffc06890ee071fa17d3dea44a.png

2pi, RMS Xmax limited for 2x drivers (modelled together because they share the same cabin), tuned to 75hz. So lowest max output in a 4x 12" driver situation would be ~137dB (between 300-400hz). 70-200hz would enjoy 141dB max output at RMS.

The 4x 21" woofers I have now would be able to match them (~131dB each from 32hz) in the cabins I designed.

 

 

 

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6 minutes ago, Droogne said:

The DE360 only goes down to 1200hz, and my synergy stops at 700hz.

Yea I'll likely cross it at around 1.5k. I think a three way will be the better choice if your crossover will be that low.

6 minutes ago, Droogne said:

What would you recommend for inside EQ (in a 'chaotic room'). Just EQ down to 500hz?

You'll need to get rid of all reflections which make its way into the mic. Since the mic is omni, you basically have to eliminate all reflections ideally (resulting in an anechoic chamber).

Your horn is quite big so the mic distance should ideally be at least twice the largest dimension of your baffle (the diagonal in most cases which results in a mic distance of over 2m for you), but the closer your mic is to your sound source, the louder it is in relation to the reflections. I think you'll get decent results if your mic is between .5 and 1 meter away from the speaker and you hang blankets on the sides of the speaker and the mic. Carpet on the floor and another blanket ceiling should do the trick.

The blankets should not be touching the speaker or they will mess with the edge diffraction.

And EQ the drivers after the crossover if that's possible with your hardware. My next DIY project will be driven by a Hypex FA123 per speaker which has more than enough dsp for the task!

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I have had an interest in the K402 and AXI2050 for a while but the costs are so prohibitive.  There is a lot of information about the AXI2050 in the horn loudspeakers book, one thing to note though is that although it has a 5" diaphragm the effective surface area of the diaphragm is less than a conventional compression driver (its still obviously huge though).  Another thing to note if using these drivers at high SPL is that distortion performance in the midrange is worse than dedicated midrange drivers like the community M200 (still available), M4 (sadly out of production) and the BMS dual diaphragm mid range. 

Anyway I plan on building a similar horn to the K402 soon for the M200 (in UK paying for all the CNC work is much cheaper than a K402 and I can tweak the design for my needs).  Are any of you simulating horns in ABEC3 or similar?

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22 hours ago, peniku8 said:

B&C have optimized phase plugs inside their CD's to help with that issue and if you built some into your horn throat it should help. Would probably be too much effort for a single DIY project thou and I have no clue what those would look like.

They all have "optimized" phase plugs. Including the Celestions.

What I mean is that the Axi2050 is supposed to be good compared to most 2" exit cd's in the 10-20kHz octave but the physics mean that while it may be good for a 2" cd it will never be as smooth in this octave as is possible with a smaller diaphragm and smaller exit. Most of the top octave output for large cd's is resonance/ breakup / beaming. Just goes with the territory. There are a lot of positives for the larger cd's though. Higher output, power handling, lower distortion, deeper extension. etc. As usual it's all tradeoffs. 

Also gating can allow for useful measurements of high and mid frequencies in room. 

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8 hours ago, kipman725 said:

 There is a lot of information about the AXI2050 in the horn loudspeakers book, one thing to note though is that although it has a 5" diaphragm the effective surface area of the diaphragm is less than a conventional compression driver (its still obviously huge though).  Another thing to note if using these drivers at high SPL is that distortion performance in the midrange is worse than dedicated midrange drivers like the community M200 (still available), M4 (sadly out of production) and the BMS dual diaphragm mid range. 

Kolbrek's comments about the driver were part of the reason I looked into it. 

Actually that's not quite right. The voice coil diameter is 5" but the diaphragm itself is 7" diameter. The surface area and coil diameter is far greater than the usual 4" cd. Some of the dual diaphragm mids may be close or better it but those also do not cover the full bandwidth. 

Do you have links to detailed distortion measurements for these drivers? I've not seen any. CD's are notoriously difficult to compare as well since the lense used has such a profound effect on the behavior. 

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Have decided to place the synergies on the 2x LaScalas I still have. That way I can boost the 60-120hz. Why only 120hz? Because that is the 1/4th WL distance between the center of the LaScala and the synergy. I'm already liking it! It also brings the speakers up to earheight (and positions the right one completely above the couch) and allows horizontal placement.

 

Also, my OLED has been fixed! Apparently the motherboard crapped the bed.. was replaced in 10 minutes, but did cost me the price of upgrading to a better compression driver..

IMG_20200325_121717.jpg

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On 3/24/2020 at 9:21 PM, Ricci said:

Kolbrek's comments about the driver were part of the reason I looked into it. 

Actually that's not quite right. The voice coil diameter is 5" but the diaphragm itself is 7" diameter. The surface area and coil diameter is far greater than the usual 4" cd. Some of the dual diaphragm mids may be close or better it but those also do not cover the full bandwidth. 

Do you have links to detailed distortion measurements for these drivers? I've not seen any. CD's are notoriously difficult to compare as well since the lense used has such a profound effect on the behavior. 

I have appeared to miss read the specs and just quoted the voice coil size.  

by distortion I was referring to high frequency THD which is limited by air non linearity and not low frequency distortion so I can confidently make this statement because the phase plug design of the AXI2050 allows extension to 20 kHz while the M200 has no phase plug and the BMS has a mid-range optimized phase plug: http://www.bmsspeakers.com/fileadmin/bms-data/product_data_2014/bms_4599nd_preliminary.pdf

I'm building an old school style big stack of horns system at the moment for medium scale stuff so I have got a bit per-occupied with getting low distortion at high SPL.

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40 minutes ago, kipman725 said:

I have appeared to miss read the specs and just quoted the voice coil size.  

by distortion I was referring to high frequency THD which is limited by air non linearity and not low frequency distortion so I can confidently make this statement because the phase plug design of the AXI2050 allows extension to 20 kHz while the M200 has no phase plug and the BMS has a mid-range optimized phase plug: http://www.bmsspeakers.com/fileadmin/bms-data/product_data_2014/bms_4599nd_preliminary.pdf

I'm building an old school style big stack of horns system at the moment for medium scale stuff so I have got a bit per-occupied with getting low distortion at high SPL.

I'm planning to do some tests on mine but don't know when I'll get around to it. I'm more concerned with distortion in the lower midrange than the highs. I can't hear much past 16kHz anyway these days, so the HD of anything past 7 or 8kHz are probably of little audible consequence for me. 

The dual diaphragm mid CD's are intriguing for very high output pro apps but require a super tweeter past 8kHz or so. It makes them less useful for synergy or multi entry horn designs. 

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https://drive.google.com/open?id=1l7Pf_MkJqLrwNJE_N-kdNn-AXEGntZG8

Here is a link to the REW files of the left MEH (+ la scala). Anything to suggest that I do? What about the delays? Any remarks on the crossovers (700hz 48dB)? Would you flatten it, or boost some of the range? 

I realise those are some newbie questions I guess, but I want to get it right, and I fear I'm making some mistakes over and over. 

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5 hours ago, Ricci said:

I can't hear much past 16kHz anyway these days

Blame those rough raw gigs back in the days..! At some point I started wearing ear protection for rehearsing and don't even know how I could endure playing the drums without em pretty quickly.
I'm so happy that our band uses a full blown IEM system now, so I don't have to kill my ears with every gig. That nasty china cymbal...!

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