Peavey Pro 410 horn replacement

[Curtybob]

Just got a 410 that sounds great, save for a few minor niggles. The horn is blown, but I picked it up used at a steal of a price. I could tell right away that it is gone, so I knew what I was getting into. Not sure how this cab didn't become Peavey's flagship cab. It is, frankly, a badass sounding cab. I tossed the tweeter from my crushed eden in it, and it doesn't sound horrible... but I like a bit of distortion every now and then, and the horn tweeter makes my normal tones unbearably hissy. Without the horn, the definition lacks a little. But the blue marvels drivers that peavey loaded this cab with sound great, and do a good job of translating all my drastically different tones (I play in a pop cover variety band), including the tone I use for hip hop covers, which is incredibly reggae-scoop styled.

I have decided to rework the crossover and high freq driver, and would love some opinions about details. I read that the existing crossover is centered at 4K, which is much too high. This is my biggest dilemma. I don't mind wiring a custom crossover, just unsure as to where I should aim as a center frequency. My inclination is to go for the 1500-1800 range, and use a good quality 3" or 4" mid-driver that will fit between the speakers (only a 3.5" cutout, with not much room for expansion). But, finding a driver that has an input sensitivity of more than the low 90dB range is tough. I found a 3" FaitalPro on parts express that I am currently considering going with that is stated as having 91dB sensitivity at 1w/1m. The cab is stated as having 106 1w/1m. I'm sure that's fluffed a little... but a 15dB disparity is concerning me, and has me here looking for either approval, or better plans. lol. My thoughts is that the sensitivity may be ok, considering the usual content of bass tone, and the notion that I am keeping the attenuator down all the way with the Eden horn (Fostex horn). But, is 1500-1800 Hz going to cause problems in my tone when I get it turned up a bit? Should I aim higher, or lower? Is there a great driver that is 4.25" cutout or less?

I know... I should build a Jack 10 pair and rock on... but I have latched on to this as a project, and it's getting too cool to work without a shop. lol

[Curtybob]

After second-guessing all week while I was waiting on parts, The cab does sound good. I built the little faital driver a separate chamber by using 2 cheap plastic cups, and some epoxy to fill the space between the two layers. Turned out very stiff. Cut a baffle that is the same size as the old horn mounting flange, and epoxied the drinking glass chamber to the back side of the new mounting flange.
drilled a small hole in the chamber, fished the tweeter wires in, and hot glued the wires.

I hooked it up with the peavey crossover, and it sounded wonderful. My bass dirt pedals sound fantastic, and the snap of the strings on my clean tones sounded great. I am kind of hesitant to rework the crossover, now. I can hear where they were trying to go with this cab.

Anyway, for now, the cab sounds just like I want it too.

[Bill Fitzmaurice]

I can hear where they were trying to go with this cab.

Where they were trying to go is with the least expensive option, which means using a tweeter that can't go below 4kHz. That's the case with most commercial bass cabs. Even though tens will have some useful axial response to 4kHz off-axis is going to be poor. That's why I specify the Eminence BGH 25 in the bass versions of the Simplexx line. It's rated for 2.5kHz with a 2nd order high pass, and with the 4th order filter we use in the Simplexx it will run to 2kHz, eliminating the upper midrange off-axis droop typical of commercial cabs.

[Curtybob]

Cheap? Absolutely. It's still a Peavey. But, as compared to the rest of their cabs, this one actually sounds like a real effort was made. It even sounded that way before I replaced the tweeter... just lacked some sparkle. For my tastes, this cab sounds pretty good. Horns generally sound odd with a little dirt, and downright bad with any real distortion. This little 3", while being a fair bit quieter than I would have like to see on paper, actually gets it done, and doesn't sound harsh or honky. Although, I do have the attenuator wide open, now.

[Bill Fitzmaurice]

Cheap? Absolutely. It's still a Peavey.

No knock on Peavey, almost every manufacturer use tweeters that are crossed over way too high.

[Ryan Sober]

Cheap? Absolutely. It's still a Peavey.

No knock on Peavey, almost every manufacturer use tweeters that are crossed over way too high.

Even manufacturers who charge many times more...

[Curtybob]

Had a weird problem. Thought I bottomed out the woofers. Hard. I brought the Peavey with me to a studio writing session to see what it sounded like with a bit of volume. Got turned up to a reasonable volume, and it sounded awesome for a minute. Then... fart. Only momentarily, but it definitely farted out. turned the attenuator down for the 3" tweeter to see if I had a crossover problem. No dice. Still farts on low D. Grabbed a screwdriver and yanked the tweeter and bypassed the crossover. Sounded mostly fine, then, and got a lot of volume. Probably double. It is actually a very good sounding cab from Peavey. Engineer was digging it.

Got home, and saw that my double layer cup chamber was cracked. The woofers were dragging the tweeter along for a hell of a ride. So, had a practice coming up last night, and I decided to bodger a couple of loose off brand 1016 piezos to the horn flare from the original horn. Didn't do any math... just made a small wedge shaped box to mount the two piezos on, with an end cap that I just hot glued to the horn flare opening (left the original phase plug, too). I played around with my Frankenstein contraption by hooking it up to my phone and comparing various things, like phase plug/no phase plug, series/parallel, both piezos/one piezo). Settled on series, because it sounded a bit smoother.

Tossed the monster in the cab, and took it to practice. It actually sounded ok, too. No more farts. Maybe a bit too much hiss. Distortion was just ok. The only problem I had, which is the bigger one... is that if I hold a note out for a few seconds (especially a lower register note at higher volumes) I can hear an odd swell, and you can watch the cones all move out over the course of a second or so. Very weird. Not sure if it is caused by the piezos, my old power amp (using a Line 6 processor through an older Tapco 800 watt amp on bridge mode), or maybe even if it's the preamp on my bass acting weird.

[Tom Smit]

Do you have a 4 ohm resister in front of the piezos? If not, your amp may be protesting.