Im have the pure audio clone speakers built. Waiting for the crossover since january 
so i was a little anxious ))
I have 2 Eminence beta15 per Channel. I was missing the crossover and a 100watt amp for the woofers, because somehwhere in the thread, Nelson Pass said that it was the amp needed for the woofers. Am i right?
Now i need a little guidance and time to study. But dont know where to start
Thanks in advance
so i was a little anxious ))I have 2 Eminence beta15 per Channel. I was missing the crossover and a 100watt amp for the woofers, because somehwhere in the thread, Nelson Pass said that it was the amp needed for the woofers. Am i right?
Now i need a little guidance and time to study. But dont know where to start
Thanks in advance
IMPORTANT NOTICE!!!!!
We just got word that the PSU included in the box with the chassis connectors is incorrect.
While it is 24v, the outside barrel of the connector which plugs into the chassis is positive, while our standard is to have the inside contact be positive.
Obviously you can cut the PSU cable to the chassis, strip, flip and solder the wires so the polarity is opposite, which is a way for you to try the crossover out and should work perfectly, but we’ll be sending out the correct PSU (wall wart) to people who have already been mailed their kits. At this time I don’t know if hooking up the PSU with wrong polarity will damage anything. Will update you.
The rest of the kits won’t be sent until we can order the correct part and swap them into the kits.
This will no doubt take more than a week to resolve. We are of course very sorry for this situation.
Mark
We just got word that the PSU included in the box with the chassis connectors is incorrect.
While it is 24v, the outside barrel of the connector which plugs into the chassis is positive, while our standard is to have the inside contact be positive.
Obviously you can cut the PSU cable to the chassis, strip, flip and solder the wires so the polarity is opposite, which is a way for you to try the crossover out and should work perfectly, but we’ll be sending out the correct PSU (wall wart) to people who have already been mailed their kits. At this time I don’t know if hooking up the PSU with wrong polarity will damage anything. Will update you.
The rest of the kits won’t be sent until we can order the correct part and swap them into the kits.
This will no doubt take more than a week to resolve. We are of course very sorry for this situation.
Mark
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Not so easy.
Since the chassis mount power connector (-) is in contact with the chassis,
it's easier to cut the wall wart wires and splice them swapped.
Until the replacement wall warts arrive....
To answer the inevitable question "What happens if I just plug it in?"
Not recommended, but 6L6 did just that without damage, as the wall wart
has fold-back limiting.
Since the chassis mount power connector (-) is in contact with the chassis,
it's easier to cut the wall wart wires and splice them swapped.
Until the replacement wall warts arrive....
To answer the inevitable question "What happens if I just plug it in?"
Not recommended, but 6L6 did just that without damage, as the wall wart
has fold-back limiting.
My speakers are also PAP Trio-15 clones.
For woofers I'm building F6 amp - I think 45/50WPCH@4Ohm should be enough. For the FR driver I will use 8WPCH vacuum tube monoblocks.
Active XO basic kit is also on the way - now I need to sort out crossover parameters and then order remaining passive components.
I do fine with 25 watts. If you use an amp that will drive 25W into 8 ohms
and 50W into 4 ohms, then I think you'll be fine.
I do fine with 25 watts. If you use an amp that will drive 25W into 8 ohms
and 50W into 4 ohms, then I think you'll be fine.
oh..that's good news. I have the F5. i think it will do the trick. Maybe i 'll build the turbo, or your incoming(i think) Class AB.
Thank you for all your efforts. Best regards from Portugal!
Thanks Nelson, Ill get the basic kit and see where I get playing with simulations
There are plans for a more general crossover.
The LXmini crossover can be stuffed for a variety of loudspeakers.
You have the board and existing schematic, and I have posted a
MicroCap sim file:
www.firstwatt.com/sims/LX_MINI_V1R0.CIR for you to play with.
You can download the Windows demo version of MicroCap from:
Spectrum Software - Micro-Cap 12. Analog simulation, mixed mode simulation, and digital simulation software. SPICE and PSpice(R) compatible circuit simulator.
and alter the values to see the resulting curves.
After installing MicroCap demo, you click on the file and it launches you
into the screen showing the schematic. On the top bar, click on
Analysis, then AC, then Run, and see the result. You can edit the values
right on the screen, and after a little practice you can be doing this on
your own.
Note that the active elements in this sim are VCVS, voltage controlled
voltage sources whose value (gain) is set up as a buffer.
LX Mini crossover
Just received my kits for the Pass crossover. Nicely done. I'll be putting the kit together in a bit. Not sure which chassis I'll put it in yet. I have a fair number of dead preamps that would be good for the purpose. A friend even suggested bringing my old Epicure M4 back from the grave and replacing the active circuits with some of the Pass preamp projects including the LX Mini crossover. I must say that the chassis of the unit was nicely made from black anodized aluminum. But, it is somewhat of a collector item so I dunno....
Finally I must say thanks to Mr Pass for a great kit and Jason and company at the diyAudio store. Filled and shipped the order right away and it was delivered in a few days. Nice.....
Just received my kits for the Pass crossover. Nicely done. I'll be putting the kit together in a bit. Not sure which chassis I'll put it in yet. I have a fair number of dead preamps that would be good for the purpose. A friend even suggested bringing my old Epicure M4 back from the grave and replacing the active circuits with some of the Pass preamp projects including the LX Mini crossover. I must say that the chassis of the unit was nicely made from black anodized aluminum. But, it is somewhat of a collector item so I dunno....
Finally I must say thanks to Mr Pass for a great kit and Jason and company at the diyAudio store. Filled and shipped the order right away and it was delivered in a few days. Nice.....
Attachments
Hi all, I've been waiting a while for this or any other Pass xover to become available. Like many....
Now, do I build this for my mid / hf horns of wait till the more generic xover becomes available?
I'd have to tweak the values of cause as the xove points I'd need are different. All 2nd order, 500hz hi pass - the 6500hz for the tweeter horn.
Jump in now or wait??? Thats the question!
Love to hear your thoughts.
Now, do I build this for my mid / hf horns of wait till the more generic xover becomes available?
I'd have to tweak the values of cause as the xove points I'd need are different. All 2nd order, 500hz hi pass - the 6500hz for the tweeter horn.
Jump in now or wait??? Thats the question!
Love to hear your thoughts.
Here's my LTspice version.
I also made a nifty spreadsheet model of this. I'll clean it up and post it sometime.
Thank you Mike!
2nd order, the LXmini board will do it fine. Adds option for EQ.
You can check out the MicroCap sim if you want to model it.
HexFET - You are asking about a PCB for the N/P buffers, using K170/J74 jfets. It, as far as I know, doesn't currently exist for sale. Nelson may have made a prototype that way?? Maybe he has a few laying around ? No idea...
The current PCB uses the J113 Jfets in an all-N channel arrangement with some neat tricks engineered by Nelson to run them right in their sweet spot and get distortion and noise numbers extremely close to the K170/J74 version. It sounds fantastic, and doesn't use $400 worth of Jfet for the 2-way version.
The current PCB uses the J113 Jfets in an all-N channel arrangement with some neat tricks engineered by Nelson to run them right in their sweet spot and get distortion and noise numbers extremely close to the K170/J74 version. It sounds fantastic, and doesn't use $400 worth of Jfet for the 2-way version.
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