Dear Nelson Pass,
Great thanks for this new publication !
You write there :
If your speakers are not perfect, then this is just the beginning of the process, as the driver frequency response and phase shift are additional unwanted elements in the crossover. My good friend Siegfried Linkwitz dealt with this issue by adding additional filters for the individual drivers to correct for these deficiencies, however, he also noted that adjustment of the crossover itself could often accomplish it or something similar.
To simplify the integration of loudspeakers frequency responses, please find a VituixCAD project (replace .txt with .vxp after download) for .frd measurement files implementation (flat 80dB by default).
Best regards, Jean-Marc Plantefève.
Great thanks for this new publication !
You write there :
If your speakers are not perfect, then this is just the beginning of the process, as the driver frequency response and phase shift are additional unwanted elements in the crossover. My good friend Siegfried Linkwitz dealt with this issue by adding additional filters for the individual drivers to correct for these deficiencies, however, he also noted that adjustment of the crossover itself could often accomplish it or something similar.
To simplify the integration of loudspeakers frequency responses, please find a VituixCAD project (replace .txt with .vxp after download) for .frd measurement files implementation (flat 80dB by default).
Best regards, Jean-Marc Plantefève.
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Greetings Jean-Marc, I am very pleased to see you here. As you are aware,
I am an admirer, having borrowed the topology of your Profet amplifier
for the F5 and F7.
I went to the site, and the software is impressive. It will, however take
me some time to become accustomed to it, being old and having spent
most of my time with MicroCap.
+ 
However I am sure the bright boyz who inhabit this forum will pick it
right up.
So thank you very much.
I am an admirer, having borrowed the topology of your Profet amplifier
for the F5 and F7.
I went to the site, and the software is impressive. It will, however take
me some time to become accustomed to it, being old and having spent
most of my time with MicroCap.
+ However I am sure the bright boyz who inhabit this forum will pick it
right up.
So thank you very much.
You could end up with lower distortion and noise by replacing the J113 with 2SK170 (at least on the buffer transistors). Leaving the J113 in for the current sources probably makes sense (per Nelson's article), and would leave some more LSK170s in stock for everyone else in the process!
Be advised that the pinout will absolutely require some tweaking, as the J113 and 2SK170/LSK170 definitely do have different pin ordering, and you'll need to replace the biasing resistors when you make the swap.
My plan is to build it with the J113 first, and then experiment with replacing the transistors later.
Similar to you, @soleboy, I have a B4 in play currently with a pair of JBL 4344 - fantastic combo! Looking forward to the added possibilities with another active crossover.
Hi Matt,
How is the LR 12 dB filter going for you that l simulated in LinearX Leap 5?
To that end if you are interested in this kit a good way to get into it is to convert an existing full passive two way loudspeaker to Biamp.
The easiest and most effective way to do this is to measure signal voltage drive from the passive crossover at the loudspeaker terminals. A test and measurement setup such as REW and a power amp will allow you to measure and plot the voltage drives of the woofer and the tweeter. Save these measurements. Refer to the REW help guide elsewhere on www.
Then remove the passive crossover and connect up the active crossover kit to the power amp(s) with the signal from REW plugged into the crossover kit. Connect REW to measure the voltage drives again.
By adjusting the pots in the crossover kit start to dial in the voltage drive to match the passive voltage drive. This may require adjustments to the slope and frequencies. I suggest starting with LR12 slopes.
Note that the voltage drives in the region below 100 hertz will not match due the the impedance of the woofer across the crossover inductor. This is seen as bump(s) of 1 or 2 dB in the voltage drive and sometimes passive gain from the passive filter. Without measurements you would not believe it! This is an untold reason why actively driven woofers have superior bass.
Once you have a close match you are right to go. I suggest a large film cap on the tweater to avoid potential damage.
It’s much easier to learn how to use the active crossover kit by association with an existing loudspeaker you are familiar with. Attempting to learn how to set up the crossover kit and learn how to drive a simulator and design a loudspeaker from scratch is a huge leap of faith. A simulation is only as good as the data you put in. Good acoustic measurement of a loudspeaker are not easy. This is why measurement of the voltage drives gives you a blueprint for setting up the active crossover. And besides you have an existing loudspeaker you are familiar with.
I hope you find this useful.
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It’s not the same as the old day’s!
https://www.diyaudio.com/forums/pass-labs/14871-thanks-karen.html#post172800
Might be time for a new diy diva 👩*🎤.
Can’t have the kid’s waiting in the car at MacDonald’s for too long.
The crossover is now available at the store, thanks for your patience!
DIY Biamp 6-24 Crossover – diyAudio Store
DIY Biamp 6-24 Crossover – diyAudio Store
I just ordered 3. The description doesn’t mention it, but I think it includes the jfets and matching resistors along with the PCB. All other parts are extra. Not sure if a parts kit will be offered, since there is a wide variety of uses for the board which will change some of the component values depending on use.
Parts kits are in the works. At the same time, the board parts not included
in the essentials kit are listed in the BOM with source and part numbers
from Digikey and Mouser. Since the C and C/2 capacitors are dependent
on the frequency range you want, it is possible that even if you buy the
complete kit you will need to source those.
in the essentials kit are listed in the BOM with source and part numbers
from Digikey and Mouser. Since the C and C/2 capacitors are dependent
on the frequency range you want, it is possible that even if you buy the
complete kit you will need to source those.
