I was at KEF from the mid 70s to the late 90s and yes it was. Thanks. During those years, Peter Baxandall was also used as a consultant, to optimise the trickier electronics projects.
No. Absolutely not. KEF did not ever produce one of those Theile/Keele 6th order reflex designs. One Friend stage was normally used to lower the cut-off frequency of the second order response of a closed box or couple cavity design. I did once use a cascade of two friend circuits to equalise and extend the 4th order low frequency cut-off of a studio monitor reflex design but it remained 4th order.
The Friend circuit is the Friend circuit. It is a single op-amp biquad. It is simillar to the Delyanis single op-amp bandpass circuit but with two extra resistors giving a third input port to allow for different f and Q in the numerator and denominator of the transfer function to be implemented. If you have a fixed second order transfer function to implement then it is the most efficient (canonical) topology to adopt 😎 .
If you want to vary f, Q, etc. with a pot then it is not suitable at all
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What most people call a state variable filter is normally some sort of two integrator loop. This needs at least 3 op-amps to implement a second order function but has the advantage of allowing seperate pots to control f and Q independantly. Other variants with 4 or more op-amps allow more functions.
No. Absolutely not. KEF did not ever produce one of those Theile/Keele 6th order reflex designs. One Friend stage was normally used to lower the cut-off frequency of the second order response of a closed box or couple cavity design. I did once use a cascade of two friend circuits to equalise and extend the 4th order low frequency cut-off of a studio monitor reflex design but it remained 4th order.
The Friend circuit is the Friend circuit. It is a single op-amp biquad. It is simillar to the Delyanis single op-amp bandpass circuit but with two extra resistors giving a third input port to allow for different f and Q in the numerator and denominator of the transfer function to be implemented. If you have a fixed second order transfer function to implement then it is the most efficient (canonical) topology to adopt 😎 .
If you want to vary f, Q, etc. with a pot then it is not suitable at all
. What most people call a state variable filter is normally some sort of two integrator loop. This needs at least 3 op-amps to implement a second order function but has the advantage of allowing seperate pots to control f and Q independantly. Other variants with 4 or more op-amps allow more functions.
Send it to me and I 'll get it to fit. I'll drop you a line privately so you have my mail address.
Right, I have the schematics, but there's a lot to do and I have to go to work now. I'll get them up probably on Friday.
Thanks for the offer, Richie00boy, but I don't think your website is an appropriate place for this information. No offence, but I'd rather it was not hosted there.
A general audio forum like this is OK and the KEF speaker forum over at http://www.hifiloudspeakers.info/speakertalk/index.php is probably better.
A general audio forum like this is OK and the KEF speaker forum over at http://www.hifiloudspeakers.info/speakertalk/index.php is probably better.
Well it would just be a link on here, not on the website as such. But I think I can see your point even though I'm just a hobbyist rather than a business.
Anyone belong to the KEF forum @ hifiloudspeakers.info?
The email address for administration to get an auth code to join the site is bouncing. I could use a bit of a hand 🙂
The email address for administration to get an auth code to join the site is bouncing. I could use a bit of a hand 🙂
I know this is an old thread, but it keeps popping up in Google searches.
I'm constructing a new power supply for a 104/2 KUBE, and have located an 18VAC transformer (plug-in) with 3 secondary screw terminals for connecting the cord.
Now I need to source some 3 conductor insulated wire and a 5-pin 270 degree male DIN plug. What's my cheapeest or easiest source to find this stuff, since radio shack no longer carries stuff like this? Somewhere on-line perhaps?
Thanks.
I'm constructing a new power supply for a 104/2 KUBE, and have located an 18VAC transformer (plug-in) with 3 secondary screw terminals for connecting the cord.
Now I need to source some 3 conductor insulated wire and a 5-pin 270 degree male DIN plug. What's my cheapeest or easiest source to find this stuff, since radio shack no longer carries stuff like this? Somewhere on-line perhaps?
Thanks.
OK, I got a Honeywell 18VAC xfmr, and found the 270 degree 5 pin male DIN plugs in a lot of 15, on eBay for pretty cheap. The wire I should be able to find at home depot by the foot I believe. If this works, and I can build several of these, would anyone be interested in having me make them a replacement power supply for their Kube? I'll have extra plugs so I could always order some more transformers and wire.
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