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Was hoping to post finsihed photos of my SLA Pro and Tuba 24 today but ran into a problem last night.

Build the SLA Pro to plan with the following changes. Port on back, used Dayton 6" PA speakers. The first one I finished this weekend sounds great.

Finished the 2nd sla pro last night and it does not sound nearly as good as the first. The bass sound is weaker and it just does not have the overall nice rich sound as the first one. Tweeters seem OK, I think it a woofer issue. The woofers do not have a xover circuit so the wiring should be simple. Need some ideas on trouble shooting. Here is what I did so far:

Shut off sub.
Moved speaker around to verify not location issue.
Checked polarity with 1.5v battery. All 4 woofers move in same direction.
Removed filters and just playing full range to eliminate source issues.
Swapped speaker wires, L/R.
Verified all 8 drivers are working.
Pulled the terminals and double checked connections.
Not just me, wife noticed it too immediately.

None of those helped. I noticed some of the dampening looks like it is touching the terminals but I wasn't sure if that could be an issue. Looks like on the good one same thing. Also I slipped installing one of the woofers screws and made a tiny hole in the surround with the screw driver. I was able to glue it with a drop super glue (can't even see it) but I doubt that small imperfection would be so noticeable with 4 drivers.

This weekend I played the first 1 one pretty hard for several hours. Is it possible it just needs to be broken it?

I don't know what else to try. Sorry for the long post, any touble shooting ideas greatly appreciated. I need to get this resolved ASAP.

With 4 woofers I am sure that you have a combination of series and parallel wiring, double check it. Also test each driver individually to see if one is bad, I know they all moved in the same direction with the battery test but still check sound quality individually. You can also test each woofer individually with an ohm meter to see if one gives an odd reading.

I don't think that the small hole will have any effect especially since you did repair it.

You need to keep troubleshooting and isolating individual components until the problem is found.

I was very careful with the wiring, using marked wires to not get mixed up. When doing the wiring does it matter where it starts. For example on the negative I went from the jack to the top woofer and ran a jumper from that terminal to the 2nd woofer down (negative stops there). Did the same thing on the one that works well.

For the + I started at the bottom driver, than ran a + jumper up to the next one (pos stops there). Rest of the wiring was just jumpers following the plans.

Used crimped spades, gave then all a good tug to make sure they were on good. Should I have used soldering? There are on really good. Hard to remove.

If a wire is touch a speaker magnet would that cause a problem?

I used spades and wire nuts for mine. But I soldered the spades and then shrink wrapped them.

Wire nuts connected the ends to the crossover.

I would test each individual driver connected by itself. I did this with my Alpha 6s just because I wanted to hear them... then decided it would be a good idea to test them all before installing.

johns811 wrote:
Finished the 2nd sla pro last night and it does not sound nearly as good as the first. The bass sound is weaker and it just does not have the overall nice rich sound as the first one. .

That's probably a driver that's reverse wired.

Would it be possible to have a wire wrong and still pass the polarity test with the 1.5 battey?

Bill Fitzmaurice wrote:

johns811 wrote:
Finished the 2nd sla pro last night and it does not sound nearly as good as the first. The bass sound is weaker and it just does not have the overall nice rich sound as the first one. .

That's probably a driver that's reverse wired.

johns811 wrote:Would it be possible to have a wire wrong and still pass the polarity test with the 1.5 battey?

No. If all the cones move the same direction then it's not a polarity issue.

I checked with a 1.5 battery and all 4 6" moved outward on +. I was very careful on the wiring. Could it be possible just a break in issue? I played the one that sounds better pretty hard for quite a while this weekend.

Bill Fitzmaurice wrote:

johns811 wrote:Would it be possible to have a wire wrong and still pass the polarity test with the 1.5 battey?

No. If all the cones move the same direction then it's not a polarity issue.

Some of the stuff we built definitely has that issue. Try running hard for an hour or two and see if it starts to break in and match its mate.

Did some break-in and they appear to be sounding more similar. I think there is some quality/tolearance issues on the cheaper Dayton drivers. To me the bottom one the one speaker does not sound the same. I'm going to keep playing them for a while before I start swapping anything out.

johns811 wrote:Did some break-in and they appear to be sounding more similar. I think there is some quality/tolearance issues on the cheaper Dayton drivers. To me the bottom one the one speaker does not sound the same. I'm going to keep playing them for a while before I start swapping anything out.

Considering the price that's not surprising, and why I recommend Eminence. If it does turn out you've got a bad driver I'd get PE to replace it.

Thanks to mikey on this site I got all 8 of for $100 plus shipping , otherwise this would have been more than I wanted to spend. Managed to make the pair for right around $200 so I think I did pretty good. Will post photos hopefully tomorrow.