Don´t know if this pdf help you "understand" some more,Dave, Albert wrote some about his xover for the VR4 to VR5 upgrade.
In the VR2 review it´s some more text
The crossover is attenuated at 24dB per octave—with acoustic, not electrical, slopes. On his website, Von Schweikert states, "Proprietary circuits form steep 24dB acoustic crossover slopes at specially selected frequencies without the penalties of induced ringing and excessive phase delay. These slopes are necessary to limit lobing effects and non-linear off-axis response, and actually enable the consistent phase behaviour necessary between drivers. The architecture of the circuitry resembles first and second order filters combined with zobel conjugate compensators in parallel. By using a minimum of high quality parts in series with the drivers, the sound remains transparent, yet the control over phase and amplitude can be corrected with the paralleled zobel circuits."
https://positive-feedback.com/Issue25/vr2.htm
The crossover is attenuated at 24dB per octave—with acoustic, not electrical, slopes. On his website, Von Schweikert states, "Proprietary circuits form steep 24dB acoustic crossover slopes at specially selected frequencies without the penalties of induced ringing and excessive phase delay. These slopes are necessary to limit lobing effects and non-linear off-axis response, and actually enable the consistent phase behaviour necessary between drivers. The architecture of the circuitry resembles first and second order filters combined with zobel conjugate compensators in parallel. By using a minimum of high quality parts in series with the drivers, the sound remains transparent, yet the control over phase and amplitude can be corrected with the paralleled zobel circuits."
https://positive-feedback.com/Issue25/vr2.htm
VR-1 Loudspeakers: Measurements, Listening Window, Total Harmonic Distortion + Noise
https://www.soundstagenetwork.com/measurements/vonschweikert_vr1/
https://www.soundstagenetwork.com/measurements/vonschweikert_vr1/
Could I just gently point out that references to the VR2, 3, 4, 5, 6 (whatever) filters & other characteristics are meaningless here? The VR1 (totally different speaker) is what is under discussion.
FWIW though, as a brief OT, as far as the then-contemporary infomercial posted above about the VR4-5 et al is concerned, what esentially appears to be referred to is a symmetric acoustic 4th order filter with impedance correction & a ladder delay network.
Be still my heart.
Okay -in fairness, this is advanced design in the scheme of things, especially at the time, so all due kudos for pulling off a quality filter. But it's hardly an unknown quantity either. And as noted, irrelevant to the VR1. As for the rest -predominantly meaningless commercial hi-fi verbiage.
Back to the (relevant) VR1 then...
FWIW though, as a brief OT, as far as the then-contemporary infomercial posted above about the VR4-5 et al is concerned, what esentially appears to be referred to is a symmetric acoustic 4th order filter with impedance correction & a ladder delay network.
Be still my heart.
Okay -in fairness, this is advanced design in the scheme of things, especially at the time, so all due kudos for pulling off a quality filter. But it's hardly an unknown quantity either. And as noted, irrelevant to the VR1. As for the rest -predominantly meaningless commercial hi-fi verbiage.
Back to the (relevant) VR1 then...
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it's always hard when you always think you have known & can do everything about a complex subject, then someone comes along who is way ahead in development and suddenly you're in like middle school again
No offence but Albert was really "one of a kind", and if no component is "broken" in Luigi´s xover, i think Luigi can´t make his VR1 sound better.
Just my own opinion
No offence but Albert was really "one of a kind", and if no component is "broken" in Luigi´s xover, i think Luigi can´t make his VR1 sound better.
Just my own opinion
And no offense in return, but you seem to be making fan-claims without any engineering basis. The pictures show a fairly simple filter, nothing particularly fancy. Almost certainly well designed, but hardly worth elevating to the status of mysticism. Same as that old infomercial / advertising copy you posted. A bit of rationality is needed here, rather than swallowing the marketing story.
As it happens, I agree that I wouldn't touch the filter myself if none of the components are shot -but not for the reason that either it, or Albert (excellent designer though he was) is an object of cult worship. I simply wouldn't waste my money on potentially expensive components that are unlikely to be much, if any, better than the originals, especially in what was not an especially expensive speaker when it was new. No harm in doing so of course if that's what floats your boat, and if you believe it will sound better, then you'll probably be happy. The only time I would make changes though is if I were dissatisfied with the sound in the first place & was redesigning the filter as a whole to better suit xyz requirements -and I doubt I'd be stumping up for high price components.
As it happens, I agree that I wouldn't touch the filter myself if none of the components are shot -but not for the reason that either it, or Albert (excellent designer though he was) is an object of cult worship. I simply wouldn't waste my money on potentially expensive components that are unlikely to be much, if any, better than the originals, especially in what was not an especially expensive speaker when it was new. No harm in doing so of course if that's what floats your boat, and if you believe it will sound better, then you'll probably be happy. The only time I would make changes though is if I were dissatisfied with the sound in the first place & was redesigning the filter as a whole to better suit xyz requirements -and I doubt I'd be stumping up for high price components.
Totaly agree with you about the VR1 xover, and maby people missunderstand my point in all.
All i was meaning with my posts/text/attachments, was to "show" Luigi that the designer (Albert) was very skilled.
So Luigi get that info "proven", and maby think twice before he begain spending money and time into it.
And in many cases you can modify a commercial speakers xover and notice a great "update", but Alberts desings is not among these.
best regards John
I probably spent far too much time on this tonight ...
Somebody has already done an "upgrade" on the VR-1:
https://www.audioasylumtrader.com/ca/listing/Speakers-Monitor/Von-Schweikert/VR-1/Monitor/36689
Boutique and bypassed capacitors and Mills resistors. $150 worth. Says it was worth it. Well, maybe...
I also tried to reverse engineer the crossover:
4uF and 10uF capacitors. A 0.25mH labelled L2. The coil at the bottom is obviously quite large, maybe 2mH, but I don't know.
I mirror flipped the circuit board for comparison:
I guess the green and black W for Woofer and red and black T for Tweeter is right, but I am not too sure about anything here. Maybe you can check.
I think I can see the 4R and 10R resistor connections and maybe L2 and the bass coil L1, but really I am confused.
It's not making sense to me at all. And I am usually quite good at these things.
Not impossible that the bass circuit is a big coil, with a shunt 4uF, 0.25mH and 10R resistor forming an LCR 5kHz notch to take out typical 6" breakup.
Then the tweeter circuit is 10uF, small shunt coil and 4R is series with a 4 ohm tweeter.
But must sleep on it.
Best, Steve.
Somebody has already done an "upgrade" on the VR-1:
https://www.audioasylumtrader.com/ca/listing/Speakers-Monitor/Von-Schweikert/VR-1/Monitor/36689
Boutique and bypassed capacitors and Mills resistors. $150 worth. Says it was worth it. Well, maybe...
I also tried to reverse engineer the crossover:
4uF and 10uF capacitors. A 0.25mH labelled L2. The coil at the bottom is obviously quite large, maybe 2mH, but I don't know.
I mirror flipped the circuit board for comparison:
I guess the green and black W for Woofer and red and black T for Tweeter is right, but I am not too sure about anything here. Maybe you can check.
I think I can see the 4R and 10R resistor connections and maybe L2 and the bass coil L1, but really I am confused.
It's not making sense to me at all. And I am usually quite good at these things.
Not impossible that the bass circuit is a big coil, with a shunt 4uF, 0.25mH and 10R resistor forming an LCR 5kHz notch to take out typical 6" breakup.
Then the tweeter circuit is 10uF, small shunt coil and 4R is series with a 4 ohm tweeter.
But must sleep on it.
Best, Steve.
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