I built a pair of cabinets based on a design taken from the Eminence loudspeaker design book (since lost). These cabinets have been sitting around for several years now acting as little more than a table. Now I believe the time is right to finish them off. Problem is that I lack the knowledge and experience to design the x-over and select the correct bass driver and high frequency driver. I’m hoping that someone will help me make the right decision first time round.
I’ve only a basic understanding of circuit design but I can solder components if I’m given detailed component specifications and a circuit diagram.
The cabinets were designed to take a 15”driver and a horn for the high frequencies. They have the following dimensions: -
H31”
D17.5”
W22.5”
I hope to combine these with an existing pair of 18”, 500w, 8 ohm, per channel single scoop bins (H31” D27.5” W24”) to provide a lovely full range 2K system. I have a Behringer Europower EP2500 amp that I believe will run this proposed system nicely @ 4 ohms or even better @ 2 ohms. That is if I can match the impedance of the speakers with some nice wiring.
I was thinking of Eminence or Fane components and possibly making a 2 way X-over. Has anyone experience in PA speaker design and construction who might be able to provide recommendation for components and if applicable x-over circuit diagram to match?
I’m happy to purchase x-overs but I’m always confused that, generally, the power handling seems far less than that of the drivers available today. For example, the Eminence website indicates that they manufacture drivers that are over 1k but all their x-overs are rated a 400w….Seems odd to me.
I’ll be needing detailed specifications,
Thanks in advance!
I’ve only a basic understanding of circuit design but I can solder components if I’m given detailed component specifications and a circuit diagram.
The cabinets were designed to take a 15”driver and a horn for the high frequencies. They have the following dimensions: -
H31”
D17.5”
W22.5”
I hope to combine these with an existing pair of 18”, 500w, 8 ohm, per channel single scoop bins (H31” D27.5” W24”) to provide a lovely full range 2K system. I have a Behringer Europower EP2500 amp that I believe will run this proposed system nicely @ 4 ohms or even better @ 2 ohms. That is if I can match the impedance of the speakers with some nice wiring.
I was thinking of Eminence or Fane components and possibly making a 2 way X-over. Has anyone experience in PA speaker design and construction who might be able to provide recommendation for components and if applicable x-over circuit diagram to match?
I’m happy to purchase x-overs but I’m always confused that, generally, the power handling seems far less than that of the drivers available today. For example, the Eminence website indicates that they manufacture drivers that are over 1k but all their x-overs are rated a 400w….Seems odd to me.
I’ll be needing detailed specifications,
Thanks in advance!
Hi,
Point your browser towards Studiospares in the
UK and buy the parts for one of their systems.
1kW drivers, yeah right ... see
http://sound.westhost.com/project117.htm
and
http://sound.westhost.com/articles/pwr-vs-eff.htm
/sreten.
Point your browser towards Studiospares in the
UK and buy the parts for one of their systems.
1kW drivers, yeah right ... see
http://sound.westhost.com/project117.htm
and
http://sound.westhost.com/articles/pwr-vs-eff.htm
/sreten.Thanks for your advice sreten, the information from sound.westhost.com was very informative indeed. Although it would would seem that all manufacturers would utilise the maximum output efficiency when rating their drivers a bit like Peak Music Power compared to AES or RMS. So checking output efficiency, sensitivity, impedance and frequency response chart should be enough to choose a decent driver.
Your recommendation, Studiospares, don't have much of a parts selection on-line i.e. no compnent kits or detailed advice as I require. I've ordered a catalogue and will look further though.
On a separate note I hope to configure a balanced system with 500w per speaker (4 speakers including my scoops) to 2 or 4 Ohms per channel to suit my EP2500 amp. I worry that this won't be possible if I look at these new speakers separately to my existing scoops.
Your recommendation, Studiospares, don't have much of a parts selection on-line i.e. no compnent kits or detailed advice as I require. I've ordered a catalogue and will look further though.
On a separate note I hope to configure a balanced system with 500w per speaker (4 speakers including my scoops) to 2 or 4 Ohms per channel to suit my EP2500 amp. I worry that this won't be possible if I look at these new speakers separately to my existing scoops.
aim said:
An open ended question that not a lot of us would touch with a 10 foot pole. Getting a 15"/1" PA to sound like anything isn't trivial, and I'd suspect that anyone who has done it isn't giving away any of their secrets.
If the cabs aren't committed to a 15"/1" yet, you may think about a 15"/8"/1", or 2x12, or go to a 2" (Selenium D3305) if you want to stay 2 way with a 15". A 15/8/1 is at least WORKABLE with a stock x/o with an L pad on the highs.
aim said:
The problem is that you're putting the cart before the horse. You decide on your drivers and then build the cabinet. You may be able to get something to "fit", but it'll be more by luck than design.
My suggestion, find another copy of that book that you lost and buy the correct drivers for your cabinet.
The EP2500 is quite a good PA amp, and it'll take a lot of punishment (for the price). I've got one, but I'm not going to use it for anything other than a subwoofer (and this house is too small). You may want to look for a good amplifier, as your highs will probably sound bad with this amp...
Re: Re: Home made cabinets require drivers and x-over. Any recommendations?
wg ski…A fair point but that’s why I came here. Looking at the posts there's a lot of knowledge shared on complicated subjects.
With regards to modifying the design to include more drivers, I’d prefer to stick to the original specification of just a 2 way system. I was also under the impression that this would be easier to complete due to less parameters in the equation.
cloth ears… I see where you’re going but these cabs were built from a professional design, and finished to a high standard even if I do say so myself. Although I’m well aware of the differences between all the available 15” drivers, I believe that there must be similar drivers available today if not better. In fact, if my memory serves me well, the book suggested a range of suitable drivers.
With regards to the EP2500 amp, I bet you’re right but this is a PA system that will probably be used in combination with other, smaller, sound systems to provide more clarity in the mid/high end. I must admit that I was impressed with the build quality of the EP2500 for only £220! There’s no way you could get such an amp for that price a few years back.
However, after looking in more detail at the EP2500 specifications it does appear that it will only run 1 set of 450w per channel speakers (seems that @ 20 – 20Khz it’ll only do 450w @ 8ohms). So, I’ll need to buy another one to run both my scoops and these new builds. If you can think of an alternative amp with better frequency response for a similar price, I’d defiantly like to hear about it.
Brett… I believe the volume is as follows: -
12 206.25 cubic inch or 200 024.599 95 cubic centimeter (they're big!)
The book indicated that these are to be sealed enclosures and no cutouts have been made so far. My budget is going to be in the £300 mark to fix out both speakers; I’m sure I can get a decent setup for this (well I hope)
Thanks to all of you for your help so far, if we can get to an agreement on what to choose (drivers, horns and x-overs) I’ll be sure to send a picture and comment on the sound quality.
wg_ski said:
wg ski…A fair point but that’s why I came here. Looking at the posts there's a lot of knowledge shared on complicated subjects.
With regards to modifying the design to include more drivers, I’d prefer to stick to the original specification of just a 2 way system. I was also under the impression that this would be easier to complete due to less parameters in the equation.
Cloth Ears said:
cloth ears… I see where you’re going but these cabs were built from a professional design, and finished to a high standard even if I do say so myself
. Although I’m well aware of the differences between all the available 15” drivers, I believe that there must be similar drivers available today if not better. In fact, if my memory serves me well, the book suggested a range of suitable drivers.With regards to the EP2500 amp, I bet you’re right but this is a PA system that will probably be used in combination with other, smaller, sound systems to provide more clarity in the mid/high end. I must admit that I was impressed with the build quality of the EP2500 for only £220! There’s no way you could get such an amp for that price a few years back.
However, after looking in more detail at the EP2500 specifications it does appear that it will only run 1 set of 450w per channel speakers (seems that @ 20 – 20Khz it’ll only do 450w @ 8ohms). So, I’ll need to buy another one to run both my scoops and these new builds. If you can think of an alternative amp with better frequency response for a similar price, I’d defiantly like to hear about it.
Brett said:
Brett… I believe the volume is as follows: -
12 206.25 cubic inch or 200 024.599 95 cubic centimeter (they're big!)
The book indicated that these are to be sealed enclosures and no cutouts have been made so far. My budget is going to be in the £300 mark to fix out both speakers; I’m sure I can get a decent setup for this (well I hope)
Thanks to all of you for your help so far, if we can get to an agreement on what to choose (drivers, horns and x-overs) I’ll be sure to send a picture and comment on the sound quality.
Re: Re: Re: Home made cabinets require drivers and x-over. Any recommendations?
Those dimensions you posted earlier (31" x 17.5" x 22.5") are the inside? That will give the 200 litres you quoted. I thought they were the outside measurements, that giving you about 150 litres internal.
I would look through the Eminence spec sheets and try a few of the likely drivers in Unibox. This will be tedious, but will give the most accurate results. To start you are looking for a driver with a high VAS and a Qts above .40 (for sealed).
Finding a driver that works in that box should be relatively easy, as there should be several to chose from.
aim said:
Those dimensions you posted earlier (31" x 17.5" x 22.5") are the inside? That will give the 200 litres you quoted. I thought they were the outside measurements, that giving you about 150 litres internal.
I would look through the Eminence spec sheets and try a few of the likely drivers in Unibox. This will be tedious, but will give the most accurate results. To start you are looking for a driver with a high VAS and a Qts above .40 (for sealed).
Finding a driver that works in that box should be relatively easy, as there should be several to chose from.
Agree with MJL and Iain. The 3015 or 3015LF would be my first WAG for 150L sealed. The 3015LF does really well with 4 x 4" ports as per the Eminence cab suggestions (~120L). I'd add the ports and tune them for the box, but make them able to be closed off easily so it could be used stand alone or with subs.
I'd also add a mid as 15 + 1" systems always sound lacking in the upper mids to me. An 18Sound 6ND410 would be a first suggestion.
I'd also add a mid as 15 + 1" systems always sound lacking in the upper mids to me. An 18Sound 6ND410 would be a first suggestion.
Hi guys,
OK, I should probably have made this point earlier but this system is for outdoor parties in my 31’ tipi (a mini rave system). I’m not going to be listening to classical music on this setup
I’ve taken a look at the Unibox spread sheet and its impressive but I think it’s a bit too fine detailed for me as I’m not constructing a hi-fi setup. I don’t expect miracles from this simply reasonable sound quality and loudness. I may choose to add separate speakers if I’m missing quality in the mid/top end.
My main concerns are that the end result is 4 or 8 ohm load per channel that the x-over point is manageable by both the HF compression driver and the bass driver.
MJL…You are right they were the outside measurements and these cabs are made from ¾“ ply with a slight inset on the front (about 1”). I would agree with the 150 litre assumption.
So… looking at the eminence site again I’m currently thinking about:-
Bass driver – Eminence KAPPALITE 3015 – Useable range 40Hz to 4kHz – 8 Ohm. 450W
Horn - Eminence TI2000 - 2” - 284 x 246 x 257mm (although this is a push to fit as in its huge)
Compression driver - Eminence PSD:3006 - 2” - Useable range 500Hz to 18kHz -8 Ohm -80W
X-over – Eminence PXB2:1k6 - 1.6kHz Slope 12dB/octave LP
Does this sound OK?
As both driver components are 8 ohms will the x-over ensure an 8 Ohm load to amp? And will it also reduce the power to the HF driver else it’ll pop.
Thanks again
OK, I should probably have made this point earlier but this system is for outdoor parties in my 31’ tipi (a mini rave system). I’m not going to be listening to classical music on this setup
I’ve taken a look at the Unibox spread sheet and its impressive but I think it’s a bit too fine detailed for me as I’m not constructing a hi-fi setup. I don’t expect miracles from this simply reasonable sound quality and loudness. I may choose to add separate speakers if I’m missing quality in the mid/top end.
My main concerns are that the end result is 4 or 8 ohm load per channel that the x-over point is manageable by both the HF compression driver and the bass driver.
MJL…You are right they were the outside measurements and these cabs are made from ¾“ ply with a slight inset on the front (about 1”). I would agree with the 150 litre assumption.
So… looking at the eminence site again I’m currently thinking about:-
Bass driver – Eminence KAPPALITE 3015 – Useable range 40Hz to 4kHz – 8 Ohm. 450W
Horn - Eminence TI2000 - 2” - 284 x 246 x 257mm (although this is a push to fit as in its huge)
Compression driver - Eminence PSD:3006 - 2” - Useable range 500Hz to 18kHz -8 Ohm -80W
X-over – Eminence PXB2:1k6 - 1.6kHz Slope 12dB/octave LP
Does this sound OK?
As both driver components are 8 ohms will the x-over ensure an 8 Ohm load to amp? And will it also reduce the power to the HF driver else it’ll pop.
Thanks again
No one like to comment on this selection?
Its a very common setup to have an 8ohm driver combined with an 8ohm HF driver but the impedance is usually still 8 ohms for the whole speaker. How does this happen as I can't see a way of doing this with series or parallel wiring!
Also, with x-overs, I assume that a resistor is used to reduce the power to the HF driver is this used to maintain impedance @ 8 ohms and if so surely this would require more power from the amp to due to the loss? Anyone like to explain?
Its a very common setup to have an 8ohm driver combined with an 8ohm HF driver but the impedance is usually still 8 ohms for the whole speaker. How does this happen as I can't see a way of doing this with series or parallel wiring!
Also, with x-overs, I assume that a resistor is used to reduce the power to the HF driver is this used to maintain impedance @ 8 ohms and if so surely this would require more power from the amp to due to the loss? Anyone like to explain?
aim said:
Hi,
One of the reasons why you would want to properly model a driver for a given box size is excursion. If you run out of excursion at 7 watts and your system is capable of 250 watts, that's bad news.
Unibox is for every type of speaker, not just the hifi kind.
Here's how the Kappa looks in a 150 litre vented box. F3 at 42Hz, maximum power handling within excursion limits: ~200watts. The Kappa really should be in a smaller box, around 90 litres. This would give better power handling and tighter bass response.
Vent would be 15cm diameter, 6 cm long.
Attachments
MJL21193 said:
Thanks ever so much MJL... The reason I didn't choose this driver was due to the limited 1.5khz (40Hz-1.5kHz) usable range. The 3015 have a better sensitivity (I think) @ 100.8 and a usable freq. between 40Hz-4kHz (better for the x-over and HF driver selected). Although I must admit I've not considered the excursion.
Do you think that the 3015LF would still be the better choice?
I plan on using these speakers in conjunction with 2 18" single scoop bins giving me plenty of low end. I don't plan on using these on their own.
Just going back to my point earlier, with the proposed 8 ohm drivers (both 15" and 2" HF) would the x-over ensure a 8 Ohm per channel load on the amp? I'm not 1-00% on this and there's not much info available on the Eminence site.
Thanks again!
yes, the XO will ensure constant(ish) 8 ohms across the entire band.
In a parallel XO, the cap blocks low frequencies to the tweeter by going high impedance while the inductor blocks high frequencies from the woofer by going high impedance at high frequency. So at any frequency (except the XO frequency, of course) there is only one driver effectively in circuit.
In a parallel XO, the cap blocks low frequencies to the tweeter by going high impedance while the inductor blocks high frequencies from the woofer by going high impedance at high frequency. So at any frequency (except the XO frequency, of course) there is only one driver effectively in circuit.
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