sounds interesting. as always with my projects there is 2 obstactles: time and money.
anyway, the 140db mid hi sounds reasonable so that even myself with deaf ears can hear some music again
but usually with top speakers the weak spot is 100hz. and that is where you have either efficiency with low power voice coils or high power 4inch vcoils but somehow higher moving mass meaning less efficiency. so no benefit from 140db compression driver if 100hz area is limited to more realistic 120db as always the case. no any way around the 100hz spl limitation other than using dual 15s which is somehow crazy for a home discotheque project.
anyway, the 140db mid hi sounds reasonable so that even myself with deaf ears can hear some music again
but usually with top speakers the weak spot is 100hz. and that is where you have either efficiency with low power voice coils or high power 4inch vcoils but somehow higher moving mass meaning less efficiency. so no benefit from 140db compression driver if 100hz area is limited to more realistic 120db as always the case. no any way around the 100hz spl limitation other than using dual 15s which is somehow crazy for a home discotheque project.Oh and one thing that I also do not understand is why the most expensive speakers are mostly 2way, crossing somewhere the ear is most sensitive. Are they not able to afford a midrange to help the screaching tweeter cross higher? This 2 way trend and the pricing is the things I can not get into my head.
I had the same thoughts as you 25 years ago when I was a DJ
Here are the top requirements for a transportable PA speaker
Light weight
Small
LOUD
Durable/Reliable
Low Cost
A two-way with 15" and compression driver meets all those requirements easily. The sound quality is poor but for most bands--their lack of skill tended to mask that. For DJ's playing pre-recorded music, (I was) I went with 71 KG 3-way bi-amped monsters in the club.
The issue I had was the midranges could not handle a lot of power and were not very efficient/loud when used as a direct radiator. Some idiot screams into the mic and you'll find out how durable your mid is...a 2-way can handle much more power and since the thing is producing bass, the much greater cone movement cools the voice coil much better. Bad sound is better than no sound at all. Since the 3-ways tended to be larger, heavier, much more expensive but not as reliable/durable--they became quite rare.
You can get PA 3-ways with amazing sound quality thanks to the Unity/Synergy horn, improvements in co-axial PA drivers and the BMS co-axial compression driver. None of these options are low cost but the sound quality, output and durability is there.
Seaton Sound uses PA co-axial drivers for their home theater speakers. To get "reference" of 105dB at the listening position of around 4 meters requires the mains put out 117dB. Now throw in this is required from a 100 watt home theater receiver which only gives you +20dB, you need a speaker that is 97dB at one watt...not common for home audio speakers but very common for PA speakers.
If you want to go really nuts, a BMS coaxial compression driver crossed at 450Hz and 7KHz teamed up with four 12" PA woofers would give you around 104dB at one watt and no break a sweat .... just costs a lot of money!
Here are the top requirements for a transportable PA speaker
Light weight
Small
LOUD
Durable/Reliable
Low Cost
A two-way with 15" and compression driver meets all those requirements easily. The sound quality is poor but for most bands--their lack of skill tended to mask that.
For DJ's playing pre-recorded music, (I was) I went with 71 KG 3-way bi-amped monsters in the club. The issue I had was the midranges could not handle a lot of power and were not very efficient/loud when used as a direct radiator. Some idiot screams into the mic and you'll find out how durable your mid is...a 2-way can handle much more power and since the thing is producing bass, the much greater cone movement cools the voice coil much better. Bad sound is better than no sound at all. Since the 3-ways tended to be larger, heavier, much more expensive but not as reliable/durable--they became quite rare.
You can get PA 3-ways with amazing sound quality thanks to the Unity/Synergy horn, improvements in co-axial PA drivers and the BMS co-axial compression driver. None of these options are low cost but the sound quality, output and durability is there.
Seaton Sound uses PA co-axial drivers for their home theater speakers. To get "reference" of 105dB at the listening position of around 4 meters requires the mains put out 117dB. Now throw in this is required from a 100 watt home theater receiver which only gives you +20dB, you need a speaker that is 97dB at one watt...not common for home audio speakers but very common for PA speakers.
If you want to go really nuts, a BMS coaxial compression driver crossed at 450Hz and 7KHz teamed up with four 12" PA woofers would give you around 104dB at one watt and no break a sweat .... just costs a lot of money!
bms coax is also used in the lambda labs tx3a active 3way. point source. crossed at 700 and 6500.Lambda Labs | professional acoustics
i can see that the bms coax is a good thing. eur 600 for the neo is steep but there is the less expensive ferrite too. being a cd noob, how can I know what type I should take, fer or neo, 1.4 1.5 or 2 inch? what are the dis/advantages of each? Also i can see they have some predone passive 6.3khz xover attached on one pic, missing on another . where and how to get the xover - does it come automatically with the driver? I think there is no point in experimenting since they would know best how to phase align their own coax. but a schematic would also be enough for me since I can easily do myself some aircoil. only design point would then be the woofer plus the 600hz xover which I would do in 2nd order.here is not much risk if I take this approach any more, cost is pre-known, woofer xover is quite easy. only question is where to get the bms stuff, what horn is good to go down to like 500hz or below, 90 X 50degrees, where to get it,.... sounds interesting.....
Glad I could add to the confusion!
The distributor in your region should be able to match up the crossover board, proper horn and specs for you. It is going to be a large horn so this project is going to be rather large. I think some nut on the AVS Forum used that driver and paired it with TWO 18" woofers from Acoustic Elegance--a home theater thing.
The Lambda stuff looks interesting--at quite the price. If you can find a dealer somewhere, at least you can listen to them to hear that horn.
The distributor in your region should be able to match up the crossover board, proper horn and specs for you. It is going to be a large horn so this project is going to be rather large. I think some nut on the AVS Forum used that driver and paired it with TWO 18" woofers from Acoustic Elegance--a home theater thing.
The Lambda stuff looks interesting--at quite the price. If you can find a dealer somewhere, at least you can listen to them to hear that horn.
the lambda tx3a stuff is all active which doesn t fit into my concept. i have occasional chats with the lambda designer he thinks the easy passive 3 components bms xover is bulls.... the datasheet is telling lies about the frequency response, that is one reason why he uses full active 3way dsp processing on the speaker. he obviously thinks all passive crossovers are thrash, also the yorkville unity u15's, although the horn may be good....
I ve saved up a few 1000s of these paper Euros, they re getting worth less and less by the day. f-word. So the idea of overseas purchase is waning.
Anyway - does anybody know if I can switch between presets on XTI6002 under full load, or is it needed to do the transition at low power to avoid relay arcing? In other words: Is the relay cycled during preset switching, or just the DSP filled with new data while the power stage is muted only by software?
Anyway - does anybody know if I can switch between presets on XTI6002 under full load, or is it needed to do the transition at low power to avoid relay arcing? In other words: Is the relay cycled during preset switching, or just the DSP filled with new data while the power stage is muted only by software?
so many months gone, I am still designing the crossover. however some details are fixed now: For different reasons incl. I got a a good deal, I will use the beyma 15mi100s from about 112 - 450hz crossed actively 24dB LR at the 112 hz and 12db passively at the other end around 450hz on the upcoming newly modified event 4000s. the beymas have 2 different datasheets - one with 2mm xmax and fs = 48Hz (old) and one with 4.5mm xmax. and fs = 37Hz. I am actually designing acording to the newer onehoping for the 4.5mm. volume will stay about 93 liters, but I can still play with the port resonance before the units will undergo painting. what port resonance f do you recommend for this application?
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