fEARful™ Part Twelve (12)

[Sundogue]

That's what I was afraid of. I ordered the crossovers from Leland. I guess I could have wired them incorrectly. I am getting sound out of each of the 3 drivers in both the 15/6/1 and 12/6/1.

At first, I thought maybe I hadn't seated the large drivers in each cab correctly because it's like they're trying to move when the maximum excursion starts but can't. So, I took out the big drivers sealed with gasket tape and re-installed with recex screws.

But now I'm thinking it must be the crossovers. There's 3 crossovers in each cab (1 for each of the drivers -- low, mid, and high. At least that's how Leland makes them).

I've wired the crossovers by going to the + and - listed on the low crossover, the jumping that connection to the next crossover. Does this make sense? Should I first split the input + and - six different ways instead of jumping?

Of course the problem could be with the crossovers themselves.

Are the any other troubleshooting things I could try?

I'm no crossover guru, but the ones that are, are all on the [Invalid or Expired Link Removed]

You'll get a faster response as well as the definitive answer there a lot quicker than posting here on TB.

 

[Josh Pelican]

A 15/6 is definitely not a practice amp.

It will be for me! I only have one cabinet and it's an Ampeg 810.

Are you going to be playing stadium gigs when you finish school then?

Hell no! Small venues and coffee houses only!

I think I'll go for the "smaller" ones. Either a 15/6 or 15/6 tube, then the 15 sub later on. I guess it's just a matter of choosing which one! If I bought a preamp and a poweramp, I could have a sweet little rig that I could load in one trip.

 

[mikeddd]

Tonight was a banner night!!! Finished wiring the crossovers, hooked up the drivers (drivers siting on the cab and kitchen table) and played through it a little bit. So far so good! I.E. I got sound from all the drivers and nothing caught on fire or exploded. Just a basic operational test, essentially. I'm so glad it all works!

All that's left is stuffing the cab, mounting the drivers, testing the cab for at least a week to check for anomalies and then mounting the grill. Almost there. Can't wait to put some wattage through this bad boy!

Oh yeah; new pics in build wiki.

 

[dhomer]

I've wired the crossovers by going to the + and - listed on the low crossover, the jumping that connection to the next crossover. Does this make sense? Should I first split the input + and - six different ways instead of jumping? QUOTE]

I'm trying to picture this in my mind, and I'm not certain how you got'em hooked up.. The correct way is to have the main input on EACH crossover board be a direct hookup from the input jack. A single cable from the jack to a crossover mounting board which would have a single main connector for wiring in the boards would be acceptable. The crossovers should not be interacting w/each other..

 

[Dekker]

Oh yeah; new pics in build wiki.

Hey Mike, love your build log. I think it's the most revealing log that I've seen, with warts and all. The great thing is that by documenting so thoroughly, others can see the actual steps more clearly (instead of just having an abstract list of chores).

Kudos!

Dekker

 

[anonymous02282011]

Yea, I'm having x over issues too ... my mid driver isn't sounding

Adbass - TalkBass Wiki

 

[masonsjax]

You can wire the crossover sections in parallel, I think that's how most do it, just make sure you're jumping only th inputs and that the outputs only go to speakers.

 

[mikeddd]

@Dekker: Thank you very much! Documenting the whole build has added time and work to the build process, but I feel that it's my way of giving back to the community that I've learned so much from. Plus, I enjoy build threads, especially when they get down to granular-level on how to build/wire/assemble things. I hope that folks who are considering a DIY fEARful read my build thread and learn from my mistakes.

@adbass: A few questions for you. How do you have inputs to the crossovers wired? There should be (effectively) 3 sets of wires coming from the input jack, feeding the 3 crossovers. Whether you use a terminal strip like I did, or solder two more wire onto the one wire coming from each input terminal (+ and -) doesn't matter.

Did you do the "battery test" on the mid to make sure you don't have a dead driver? Take any 1.5v battery (AAA, AA, C, D) and two wires. Connect the battery to the speaker. You should get a "pop, pop" and see the cone move as you connect/disconnect the battery. If you get nothing, the driver is dead.

I can't see the capacitors on the mid crossover; are they wired correctly? Also on the mid crossover; did you cut the PCB all the way up the right side? Check my build thread for details on this.

Finally, why do you have two caps on the lowpass crossover? There's only one cap on the LP crossover from Speakerhardware.

 

[Bardley]

X-overs look good, Mike. I plan on working on my boards today on my lunch break in the engineering shop. I work in a media production facility so I have access to the full shop. I got all the parts yesterday. Unfortunately I can't build the box at work, too.

I look forward to hearing your impressions.

 

[mikeddd]

Hey, at least you get to build the crossovers in the shop. Better than in a 100-degree garage. Ask me how I know. Are you using the PCBs from Speakerhardware? If so, don't forget to extend the cut/break on the right side of the mid board all the way up.

 

[anonymous02282011]

@adbass: A few questions for you. How do you have inputs to the crossovers wired? There should be (effectively) 3 sets of wires coming from the input jack, feeding the 3 crossovers. Whether you use a terminal strip like I did, or solder two more wire onto the one wire coming from each input terminal (+ and -) doesn't matter.

Right ... except my cab is a 15/6 (no tweet) so I have 2 sets of wires coming from the input jack feeding 2 x-overs.

Did you do the "battery test" on the mid to make sure you don't have a dead driver? Take any 1.5v battery (AAA, AA, C, D) and two wires. Connect the battery to the speaker. You should get a "pop, pop" and see the cone move as you connect/disconnect the battery. If you get nothing, the driver is dead.

Good point .. I didn't do a batter test last night, but I will tonight. It's a brand new driver, so it should be OK.

I can't see the capacitors on the mid crossover; are they wired correctly? Also on the mid crossover; did you cut the PCB all the way up the right side? Check my build thread for details on this.

Finally, why do you have two caps on the lowpass crossover? There's only one cap on the LP crossover from Speakerhardware.

Well, I bought the x-overs from Leland at speakerhardware, and I think this is either (1) a difference btwn a 15/6 and 15/6/1 or (2) the fact that I chose a 250V poly shunt capacitor. I really don't know the answer


Mike, big thanks for taking a detailed look at my build progress. Your own has helped me out tremendously.

 

[mikeddd]

You are most welcome. Good point on the 250v shunt cap. Maybe that does mean you're supposed to have two caps on the LP crossover. I have the 100v shunt and only have 1 cap and it is a 30uf cap....are your caps 60uf? Two 60uf paralleled would equal 30uf of capacitance. I guess Leland will have to answer that.

You didn't say if you extended the cut on the right side of the PCB on the mid crossover. If you did not, you have a direct short circuit and that would explain why your mid is making no sound. Surprised your amp doesn't go into protection if this is the case.


There are no instructions provided for building the crossovers from Speakerhardware. I found out about the cut by accident (and a good thing too!)The only reason I know about cutting the trace on the PCB is that I emailed Leland to ask if the mid and low pass crossovers were supposed to use the same PCB (b/c my kit came with two of the LP PCBs). In his reply that said "Yes, they use the same PCB" he included this picture:



When I asked about the red line, he explained what needed to be done. If you haven't done this, that could be the problem (again, details of the proceedure on my build page). Also check to make sure you didn't create a solder bridge across the + and - traces on the PCB. It's easy to accidentally do.

 

[Bardley]

I have already made that cut on my board last night.

 

[anonymous02282011]

You are most welcome. Good point on the 250v shunt cap. Maybe that does mean you're supposed to have two caps on the LP crossover. I have the 100v shunt and only have 1 cap and it is a 30uf cap....are your caps 60uf? Two 60uf paralleled would equal 30uf of capacitance. I guess Leland will have to answer that.

I will have a look, but yes, Lelands input would be helpful.

You didn't say if you extended the cut on the right side of the PCB on the mid crossover. If you did not, you have a direct short circuit and that would explain why your mid is making no sound. Surprised your amp doesn't go into protection if this is the case.


There are no instructions provided for building the crossovers from Speakerhardware. I found out about the cut by accident (and a good thing too!)The only reason I know about cutting the trace on the PCB is that I emailed Leland to ask if the mid and low pass crossovers were supposed to use the same PCB (b/c my kit came with two of the LP PCBs). In his reply that said "Yes, they use the same PCB" he included this picture:



When I asked about the red line, he explained what needed to be done. If you haven't done this, that could be the problem (again, details of the procedure on my build page). Also check to make sure you didn't create a solder bridge across the + and - traces on the PCB. It's easy to accidentally do.

Leland pre-built the x-overs for me, so I assume that I don't need to make any additional cuts or modifications to the boards or components.

 

[delta7fred]

... Two 60uf paralleled would equal 30uf of capacitance..

Mike

I hate to correct you but two 60uF capacitors in parallel will give you 120uF, in series they will give 30uF.

 

[mikeddd]

Thank you, delta7fred. If I'm wrong, then I'm wrong. Maybe I was thinking of resistors?

 

[mikeddd]

If Leland built them, I very highly doubt he made a mistake, but it's possible. Peek under the resistors and make sure the cut is there. Also be sure there's no solder bridges. And do the battery "pop test." Good luck.

I will have a look, but yes, Lelands input would be helpful.



Leland pre-built the x-overs for me, so I assume that I don't need to make any additional cuts or modifications to the boards or components.

 

[anonymous02282011]

If Leland built them, I very highly doubt he made a mistake, but it's possible. Peek under the resistors and make sure the cut is there. Also be sure there's no solder bridges. And do the battery "pop test." Good luck.

cool Mike. You're the man.

I emailed Leeland just to be sure, but I bet he made em up so you simply drop in and solder.

 

[Bardley]

Got my low and hi crossover boards done on my lunch break.

I will try to get the mid done tomorrow.

 

[mikeddd]

I'll be using a double-layer of quilt batting. I've seen people cut "panels" out of the batting in order to fit neatly between the panel braces. I've also seen people just make one large "sheet" of the material and cover the entire panel. Is there a best way or does it not matter? I'd imagine leaving even the skinny braces exposed would leave a small, but reflective surface which is not good. Thoughts?

ps
By this point, you gotta know I'm a little OCD.