Ok here's the problem.
I have a pair of dynaudio nuance. The drivers used are:
17w75 LQ (esotec) and the d-260 (esotec). These speakers are not really small so I want a new pair.
First I thought of buying new drivers (ss 15w8531 and vifa xt25) but I now have the idea to reuse my old speaker and eventually replace them with some new drivers.
I once bought the speakercookbook (v. dickason) and I just wanted to calculated prefered internal volumes. The formula stated is:
Vas/A
in which a= compliance ratio. When I calculate for a vented box with a quasi-third-order 1.1141 even with a 4th-order-butterworth the A=1.389.
The problem is that the calculated volume is >15 liter and I had a max. of 12.5 liter in mind.
The strange part is that Dynaudio's C1 and contour 1.3SE with nominaly the same driver both have small internal volumes. How do they do this.
Can I compensate in a filter for a box that is to small??
Ralph
I have a pair of dynaudio nuance. The drivers used are:
17w75 LQ (esotec) and the d-260 (esotec). These speakers are not really small so I want a new pair.
First I thought of buying new drivers (ss 15w8531 and vifa xt25) but I now have the idea to reuse my old speaker and eventually replace them with some new drivers.
I once bought the speakercookbook (v. dickason) and I just wanted to calculated prefered internal volumes. The formula stated is:
Vas/A
in which a= compliance ratio. When I calculate for a vented box with a quasi-third-order 1.1141 even with a 4th-order-butterworth the A=1.389.
The problem is that the calculated volume is >15 liter and I had a max. of 12.5 liter in mind.
The strange part is that Dynaudio's C1 and contour 1.3SE with nominaly the same driver both have small internal volumes. How do they do this.
Can I compensate in a filter for a box that is to small??
Ralph
Not familiar with any of these speakers, but any smaller than optimum Vb can be safely used if it's tuned aperiodically, with the tradeoff being an early LF roll off. My motto is 'acoustic solutions to acoustic problems', so while you could do it electronically, using their aperiodic vent, or better still, making your own is preferred IMO.
GM
GM
Dave,
indeed the variovent, you would suspect that being dynaudio, but no they're regular ported ones.
indeed the variovent, you would suspect that being dynaudio, but no they're regular ported ones.
rwagter said:
These allow you to get away with a smaller box than specified, and you can make your own.
dave
There are no hard & fast rules yet... althou i suspect, with calibration of denser stuffing materials, Martin King's worksheets could model them.
Basically the algorithm i use is:
1/ build as big a box as you can get away with.
2/ as far from the driver as you can get add some holes (numerous circles or a Dynaco-like slot -- the later is what i have been using of late).
Dynaco Plans
3/ make the port resistive. You can use open-cel foam inside the box against the port or a sandwich of compressed fiberglass insulation (ie Dyanaco or DynaAudio). I tend to use a combination.
The "port" stuffing is used to tune the box -- do a search for click test (post by GM), or if you can easily measure impedance tune for flattest curve.
dave
Basically the algorithm i use is:
1/ build as big a box as you can get away with.
2/ as far from the driver as you can get add some holes (numerous circles or a Dynaco-like slot -- the later is what i have been using of late).
Dynaco Plans
3/ make the port resistive. You can use open-cel foam inside the box against the port or a sandwich of compressed fiberglass insulation (ie Dyanaco or DynaAudio). I tend to use a combination.
The "port" stuffing is used to tune the box -- do a search for click test (post by GM), or if you can easily measure impedance tune for flattest curve.
dave
- Status
- Not open for further replies.