I tested for continuity, the meter jumps to 0 ohms. An Open circuit (incomplete) would have had the VU meter remain at infinity, I believe.
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fEarful 12/6 kit : a total noob build diary
- Thread starter mambo4
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I tested for continuity, the meter jumps to 0 ohms. An Open circuit (incomplete) would have had the VU meter remain at infinity, I believe.
Yes, the behavior is identical when touching the meter probes together.
My intuition is that the caps and inductors would introduce some kind of resistance between + and - , but perhaps this requires voltage to be present.
I can tell you from experience that if it is only the 3012LF coming through, you would not be happy. There would be tons of mud and no mids.
The horn, I found, did not make a huge difference for me. But I didn’t wire it through the crossover. I ran the high channel of my GK 1001 directly to the horn and controlled it with the amp. The GK high channel starts at 6k and goes up from there. I got a slight “breathiness” and some top end, but not anything to write home about.
So I’m not a great source for advice on the three way and horn control.
Sounds like you are getting there. Pictures would help. Folks helped me correct lpad issues from pictures.
The horn, I found, did not make a huge difference for me. But I didn’t wire it through the crossover. I ran the high channel of my GK 1001 directly to the horn and controlled it with the amp. The GK high channel starts at 6k and goes up from there. I got a slight “breathiness” and some top end, but not anything to write home about.
So I’m not a great source for advice on the three way and horn control.
Sounds like you are getting there. Pictures would help. Folks helped me correct lpad issues from pictures.
Should be relatively easy to hook up some full-range music playback to the amp input, such as an MP3 player or music from your phone, set amp eq flat and set playback level reasonably low, then stick your ear next to each driver to see if something is coming out. Then tweak amp eq and repeat. Quick and dirty, I know, but convincing as a cheap and cheerful go/no go test of driver/x-over function.
It occurred to me I might be able to simply disconnect the woofer & tweeter and test the mid, same for tweeter.
Or would removing the speakers form the crossover circuit kill the signal?
Or would removing the speakers form the crossover circuit kill the signal?
Passinwind
I know nothing.
- Dec 3, 2003
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Powering up crossover boards with improper (ie open) loading is a potential amp killer in some cases.
Find a frequency sweep app for your phone and run a sweep on it.
Thanks for the excellent suggestion. I did not occur to me that there would be such apps for smartphones. Today ran a frequency generator app through my amp to the cab and verified that the Woofer and Mid are fully operational. No signal could be produced from the tweeter, so I took some time to test things with my multimeter:
- tested the tweeter with a 9V battery on the terminals, got the crackling signal indicating the tweeter is functional
- double checked the numbering of the lugs and the inputs on the L-Pad :
- to common ground
- to tweeter +
- to signal + (post Capacitor #2)
- confirmed continuity across all crossover components, speaker and and jack terminals
- confirmed the l-pad resistance changes with knob position
- tested for voltages during operation and found a weak voltage was present ( just under 5V AC, but it's and old school VU meter with multiple ranges, so I'm not confident about my reading accuracy...)
I tried to get a decent shot:
Is that one board for the tweeter and mid? Can I assume the bottom left is the +IN? Bottom right is -IN? Guessing top left is supposed to be tweeter+, right side top is tweeter and mid -, and kinda middle way down on right is the mid+?
There is no signal entering the circuit from the mid. +/- IN come from the input jack. - T
In the upper right goes to tweeter -, the terminals on the middle left go to the l-pad lugs 1 and 3
In the upper right goes to tweeter -, the terminals on the middle left go to the l-pad lugs 1 and 3
I misspoke, the terminals on the middle right go to the l-pad lugs 1 and 3
I guess It's an HPF not a true crossover, as I understand the explanation.
It's greenboy's [Invalid or Expired Link Removed]
The other crossover, between the woofer and mid is pictured in this post
The Input +/- terminals on the Woofer/Mid Crossover are jumpered to the Input +/- terminals on the tweeter HPF, but there is no other connection.
I have never built a crossover circuit much less a 3 way system.
If the + IN signal was meant come from somewhere besides the jack input, this is very poorly explained.
I guess It's an HPF not a true crossover, as I understand the explanation.
It's greenboy's [Invalid or Expired Link Removed]
The other crossover, between the woofer and mid is pictured in this post
The Input +/- terminals on the Woofer/Mid Crossover are jumpered to the Input +/- terminals on the tweeter HPF, but there is no other connection.
I have never built a crossover circuit much less a 3 way system.
If the + IN signal was meant come from somewhere besides the jack input, this is very poorly explained.
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Other than this small issue with the horn, how does it sound?
I know I was less than impressed with the horns on my 15/6/1’s. But that might have been because I decided to go my own way and use the GK’s high side to power the horns. At least for bass guitar. If I was running drum machines or full range sound, the horns helped. I never got motivated enough to revisit the crossover and build out the three way. I did build a couple four wire speaker cables and I can verify that a pair of 15/6/1’s at 4 ohms, powered by a GK 1001 is serious overkill.
I was mighty pleased with the rest of the project. The fEarfuls sounded tons better than any of my other cab projects. I used them with other amps that didn’t have any way to power the horns and was just as happy.
Eventually, I built a pair of 12/6 cubes and skipped the horns.
I’m sure you’ll find your way through the wiring issue, it’s just part of the DIY process.
I found myself using the cabs with no horns and thinking, “Two out of three, sounds pretty awesome!”
I know I was less than impressed with the horns on my 15/6/1’s. But that might have been because I decided to go my own way and use the GK’s high side to power the horns. At least for bass guitar. If I was running drum machines or full range sound, the horns helped. I never got motivated enough to revisit the crossover and build out the three way. I did build a couple four wire speaker cables and I can verify that a pair of 15/6/1’s at 4 ohms, powered by a GK 1001 is serious overkill.
I was mighty pleased with the rest of the project. The fEarfuls sounded tons better than any of my other cab projects. I used them with other amps that didn’t have any way to power the horns and was just as happy.
Eventually, I built a pair of 12/6 cubes and skipped the horns.
I’m sure you’ll find your way through the wiring issue, it’s just part of the DIY process.
I found myself using the cabs with no horns and thinking, “Two out of three, sounds pretty awesome!”
Looks right to me. The only connection I can't really inspect is the first coil input from the + input. You are using the right signal in, from the terminal, so that's fine. It is still called a crossover, more descriptive is a "high-pass crossover". I would next bypass the Lpad. Connect the tweeter+ to the terminal you have labeled #3. See if that yeilds sound. Otherwise could have a bad crimp connection, bad Lpad, mislabeled Lpad?
Is sounds good. I haven't had the chance to really crank it yet. But I puts out significantly more bass than the bergantino AE 112 that was my gigging cab. As I mentioned in my previous post, the Berg sounded a lot more "boxy". I think there may be some kind of high mid peak in the berg (or a dip elsewhere), or maybe it' the tweeter. The 12/6 is comparatively very warm and smooth. I suspect that what I hear is not really more bass but a more even response as the frequencies climb from belwo ~100 hz to ~1khz. With the pbass, the results are really nice on the ear. It doesn't sound quite so "tubby" like it does through my headphone amp or the berg. The characteristic classic low mid thump of a P is complemented really nicely by this cab, I think the even response of the cab brings more of the frequencies out, and you get a fuller sound P Bass.
I have yet to try it with My J bass
I'd love to try it in a gig situation, and see how it cuts in the mix - but I'm not gigging these days.
update:
took some time checking the tweeter. First I just connected the jack terminal straight to it the tweeter +/- (at VERY low volume) and confirmed that it does respond to the test tone.
after that, I took the lead from speaker + terminal and touched it to the input then output wires of each component, confirming the signal was making it through the wires. Again, at VERY low volume.
Eventually I found the point in the circuit where the signal went dead:
The solder joint between the C2 capacitor and the ground was not complete. The lesson here is: when you test for continuity, unhook everything incoming to the crossover, otherwise the circuit may be completed elsewhere, giving you a false positive. Had I simple unhooked everything and carefully tested each component, I probaly woudl have caught this.
A quick and dirty solder job later:
and now my Fearful 12/6 is fully operational!
My daughter has already informed me that it's too loud.
I think I'll take time later this week to compose a final post, summarizing any wisdom gained.
took some time checking the tweeter. First I just connected the jack terminal straight to it the tweeter +/- (at VERY low volume) and confirmed that it does respond to the test tone.
after that, I took the lead from speaker + terminal and touched it to the input then output wires of each component, confirming the signal was making it through the wires. Again, at VERY low volume.
Eventually I found the point in the circuit where the signal went dead:
The solder joint between the C2 capacitor and the ground was not complete. The lesson here is: when you test for continuity, unhook everything incoming to the crossover, otherwise the circuit may be completed elsewhere, giving you a false positive. Had I simple unhooked everything and carefully tested each component, I probaly woudl have caught this.
A quick and dirty solder job later:
and now my Fearful 12/6 is fully operational!
My daughter has already informed me that it's too loud.
I think I'll take time later this week to compose a final post, summarizing any wisdom gained.
That solder joint needs a lot more heat on it to get the solder to flow properly rather than sitting in a blob on the surface.
The large area of copper is a really good heatsink which takes the heat away from the joint very efficiently so you need a powerful iron to counteract that.
I use a 120W instant heat pistol grip iron/gun which is useless for small jobs because it gets way too hot but ideal for getting a lot of heat into a joint quickly.
The large area of copper is a really good heatsink which takes the heat away from the joint very efficiently so you need a powerful iron to counteract that.
I use a 120W instant heat pistol grip iron/gun which is useless for small jobs because it gets way too hot but ideal for getting a lot of heat into a joint quickly.
