These show up all the time in the USA on eBay for $150 or less.
http://crestaudio.com/media/pdf/ckv800_11-20-96.pdf
The CKS800 version is 400W per channel at 8Ω, 600W/4Ω (20hz~20Khz) and are generally less than $200 (run series-parallel for a 4Ω load).
The fan does not run at all unless the amp gets hot.
The CKS800-2 is rated to drive 2Ω, and has the same circuitry (basically) as the Leach hi-fi amplifiers, they are generally less than $250 or so.
I've seen 240V/50hz ones too (may be what you need).
I have so many of this series I would have to go and count them all. They make them from 100W through 2400W models. The CKS1600-2 has the identical schematic as their 8001 Pro series, but on a larger 4-space chassis (and I bought two of these for about 1/3 or the price of a used 8001).
http://crestaudio.com/media/pdf/ckv800_11-20-96.pdf
The CKS800 version is 400W per channel at 8Ω, 600W/4Ω (20hz~20Khz) and are generally less than $200 (run series-parallel for a 4Ω load).
The fan does not run at all unless the amp gets hot.
The CKS800-2 is rated to drive 2Ω, and has the same circuitry (basically) as the Leach hi-fi amplifiers, they are generally less than $250 or so.
I've seen 240V/50hz ones too (may be what you need).
I have so many of this series I would have to go and count them all. They make them from 100W through 2400W models. The CKS1600-2 has the identical schematic as their 8001 Pro series, but on a larger 4-space chassis (and I bought two of these for about 1/3 or the price of a used 8001).
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series-parallel woofers
If I wire like this (series parallel) it would be a 4 ohm load.
Is there any effect in particular, be it for the sound or other that I should know of with this type of wiring.
Does it have an advantage over series or parallel?
Thanks for the amp recommendation as well.
If I wire like this (series parallel) it would be a 4 ohm load.
Is there any effect in particular, be it for the sound or other that I should know of with this type of wiring.
Does it have an advantage over series or parallel?
Thanks for the amp recommendation as well.
Attachments
No effect on sound (other than amplifiers may sound different into different impedance loads), advantage is achieving a desired impedance not possible with series or parallel wiring.
Personally, I would do at least 300 L net total to allow for a little thermal power distortion without it becoming audibly obvious, with up to 600 W because the drivers can theoretically handle it without exceeding Xmax and wire two pair in series, then parallel wire for 4 ohms because I doubt there's any high SQ, high power amps rated for 16 ohms.
GM
GM
"Isn't the loss of damping from the amp a drawback in series wiring?"
How could it be?
Damping factor should be at least 20 or the speaker design will be compromised.
Amplifier damping factor goes UP into high impedance loads.
How could it be?
Damping factor should be at least 20 or the speaker design will be compromised.
Amplifier damping factor goes UP into high impedance loads.
how about 96lt per woofer
I do not have space limitations. I can build bigger boxes, so I simulated a 40x40x60cm sealed box.
I simulated a single 30w4558T00 in a 96lt sealed box, and this is the graph I have. The f3 is about 29hz which is very very good for me.
I will have 8 of these sealed boxes. I will group them in fours.
By the way, 50 litres came out of sealed enclosure calculators. When I enter the values of my woofers, it gave me 50 litres and 38 hz. I thought this was the ideal size for this woofer. Does having it ideal size have any benefits? or is it not the ideal size?
I do not have space limitations. I can build bigger boxes, so I simulated a 40x40x60cm sealed box.
I simulated a single 30w4558T00 in a 96lt sealed box, and this is the graph I have. The f3 is about 29hz which is very very good for me.
I will have 8 of these sealed boxes. I will group them in fours.
By the way, 50 litres came out of sealed enclosure calculators. When I enter the values of my woofers, it gave me 50 litres and 38 hz. I thought this was the ideal size for this woofer. Does having it ideal size have any benefits? or is it not the ideal size?
"When you have one voice coil in series with another voice coil, doesn't the DC resistance of each greatly reduces the damping factor seen by the other?"
No.
No.
The back electromotive force for one driver is 1x with the voice-coil DC resistance in series.
The back EMF for four drivers is 4x with 4x the DCR in series.
Therefore the DF is the same (the DF of the amplifier is dominated by the DCR of the driver VC, and in practice immaterial unless less than 20).
The back EMF for four drivers is 4x with 4x the DCR in series.
Therefore the DF is the same (the DF of the amplifier is dominated by the DCR of the driver VC, and in practice immaterial unless less than 20).
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Ben,
No, the amp sees the driver's DCR in addition to the series resistance of the wire used. Given the same speaker cable gauge, a higher impedance results in a higher damping factor. With long cable runs one may actually hear an improvement in sound quality by running subs in series even though they draw less power from the amplifier.
This is a good article regarding damping factor:
http://www.bennettprescott.com/downloads/dampingfactor.pdf
Art
stack of small sealed subs is great solution.
Hi Kodomo,
I think you are on the right track with a pair of bass stacks.
Two, four or 6 cabinets per side depending on your max SPL requirements.
I advise looking at low Q Pro drivers with 4 or 5 inch coils, low Mms and high Bl (powerful motors).
For your reference I have attached a 12 inch sub (17.4 litres internal Vb) and an 18 inch sub in 38 litres internal Vb.
Both of these options require powerful amplifiers (800watts and 1.5Kw respectively) and Eq.
In return they offer superb tight, deep, accurate bass and massive SPL's if required....110dB to 133dB in room....!
They are obviously incredibly simple to build, are modular (add more at any time) and are tuned to 0.707 Q.....Perfect!
Good luck and hope this helps.
Cheers
Derek.
Hi Kodomo,
I think you are on the right track with a pair of bass stacks.
Two, four or 6 cabinets per side depending on your max SPL requirements.
I advise looking at low Q Pro drivers with 4 or 5 inch coils, low Mms and high Bl (powerful motors).
For your reference I have attached a 12 inch sub (17.4 litres internal Vb) and an 18 inch sub in 38 litres internal Vb.
Both of these options require powerful amplifiers (800watts and 1.5Kw respectively) and Eq.
In return they offer superb tight, deep, accurate bass and massive SPL's if required....110dB to 133dB in room....!
They are obviously incredibly simple to build, are modular (add more at any time) and are tuned to 0.707 Q.....Perfect!
Good luck and hope this helps.
Cheers
Derek.
Thanks Overkill. I already got the woofers. They are Scanspeak 30w4558t00. I got 8 of them.
I am deciding wether to enclose them in two's or one by one. It is going to be a sealed enclosure with 0.707. If I do 132 liters per two woofers sealed cabinet, the f3 is around 33hz, which is very good. I can do 4 of these sealed cabinets. Parallel wire each cabinet within and series wire them in two's. I can have 4ohm load to amp this way.
I am deciding wether to enclose them in two's or one by one. It is going to be a sealed enclosure with 0.707. If I do 132 liters per two woofers sealed cabinet, the f3 is around 33hz, which is very good. I can do 4 of these sealed cabinets. Parallel wire each cabinet within and series wire them in two's. I can have 4ohm load to amp this way.
Comparison of 12 inch drivers.
Hi Kodomo,
Thats cool, I am sure the 12 inch Scan Speaks will rock...Also a stack of 8 big boxes will look very impressive!
To give you a like for like comparison I have attached a simulation of the Scan Speak Vs one of our 12 inch drivers, both in sealed box with 0.707 Q.
The two key points I would draw your attention to are the size of the boxes ( not an issue for some) and the Mms to Bl ratio.
This thread
http://www.diyaudio.com/forums/full-range/191853-near-full-range-bmr-balanced-mode-radiator-27.html
from around post 263 gives you a real world comparison of the Peerless version of your Scan Speak subs Vs my drivers / subs.
Having a powerful motor and a light cone is key in my view... See second attachment which explains why using "elastic bands" for driver surrounds is beyond madness!! This article is obviously focusing on the CIA silk surround BMR, but the comparison is valid against any rubber surround driver....Including rubber surround BMR's!
Hope this helps and all the best
Derek.
Hi Kodomo,
Thats cool, I am sure the 12 inch Scan Speaks will rock...Also a stack of 8 big boxes will look very impressive!
To give you a like for like comparison I have attached a simulation of the Scan Speak Vs one of our 12 inch drivers, both in sealed box with 0.707 Q.
The two key points I would draw your attention to are the size of the boxes ( not an issue for some) and the Mms to Bl ratio.
This thread
http://www.diyaudio.com/forums/full-range/191853-near-full-range-bmr-balanced-mode-radiator-27.html
from around post 263 gives you a real world comparison of the Peerless version of your Scan Speak subs Vs my drivers / subs.
Having a powerful motor and a light cone is key in my view... See second attachment which explains why using "elastic bands" for driver surrounds is beyond madness!! This article is obviously focusing on the CIA silk surround BMR, but the comparison is valid against any rubber surround driver....Including rubber surround BMR's!
Hope this helps and all the best
Derek.
Somehow I miss the high sensitivity point. Amp power is so cheap these days. If you want to go ultimate, why not buy a precision devices pd 2150 (or multiple well built 18s or whichever driver suits you), build a large enough sealed box and eventually equalize the bottom end to your desire? From what I get this is supposed to paly at home hence no need for maximum spl - eventually the maximum spl on the bottom end will become your limit but I guess your ears/neighbours wont tolerate full power.
I already have the woofers as I have written before 🙂 8 of them in total!
I am grouping them in two's. I will have 4 dual-woofer boxes.
I am making each box in 132lt net volume (2.9lt per woofer and bracing added on top of 132lt)
Each box will have q 0.707
As I will have 4 dual woofer boxes, I will match the rest of the system without distorting these units with not much power.
ps. I have no neighbour problems, no space problem and no wife 🙂
I am grouping them in two's. I will have 4 dual-woofer boxes.
I am making each box in 132lt net volume (2.9lt per woofer and bracing added on top of 132lt)
Each box will have q 0.707
As I will have 4 dual woofer boxes, I will match the rest of the system without distorting these units with not much power.
ps. I have no neighbour problems, no space problem and no wife 🙂
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