LE 10 "upgrade?"

[Triumph Don]

Just recieved a pair of Radience Series R 103's, woofers need repairs. Would Alnico LE 10's work for replacements? Both are 8 ohm.

[boputnam]

Hey...

I don't know. Maybe we can model the original and the LE10 in that cabinet and see how it performs. Can you provide dimensions for the cabinet, port and duct? And, do you know what the original woofers are?

[Triumph Don]

Thanks Bob. The cabinets are 25.5" tall, 16"wide, 10,5" deep. The port is 3", 6" into the cab. Woofer is the meek looking 310 G 1, LE 25 tweeter, 305 G1 5" mid. These cabs are just a little larger than L 100"s, of course with 12's. Looks like LE10's and upgraded mids can be had for $100 to $175. What do you think?

[boputnam]

Well, I don't know the first thing about your Radiance series cabinets, and that last post is a bit ambiguous. Are the Radiance with 12-in woofers? If so, you're going to have a wobble getting a 10-in frame to fit into the existing baffle.

Maybe I got confused...

Anybody else out here know this cabinet or the "310 G 1"?

Trouble is, a different woofer will be affected by how the existing crossover works - slopes and crossover frequencies - so, you're really getting into a vague area. We need to know the entire configuration - crossover and midrange characteristics, too.

Not trying to be difficult, but your question has grown, and the objective is good sound, not mud.

[Triumph Don]

Bo- The Radiance series was made from 1979 to 1983. Mine are the model R103 with a 10" woofer, hence my question about replacing the very meek looking 310G with a more substantial LE 10, and possibly LE5 mids. This is just for fun, a little project with my 13 yr. old. His older brother has a pair of Jubals we just finished [dad has L300's] I have no way to determine the crossover points. The cabs look the same on the inside as the L100's we also have, although the veneer is not quite as nice. As you can see from the previous reply the volumetric effieciency, I would think, should be substancial for 10" woofers. Am I barking up the wrong tree or what? Thanks again, Don

[Triumph Don]

I just found a pair of 310G's like mine on eBay auction # 3067458475. My cabs have the port, not the passive radiators

[Roddyama]

If you decide to put the LE10A's into these boxes, it should work fairly well even with the same port. You'll get an f3 of about 42Hz. Here's the Bass Box Pro version.

[boputnam]

Nice job, Rod! Saved me the bother. I was wanting to model that 310 LF as comparison, but can't find the Thiele-Small parameters, in either BBPro or WinISD...

I'm might run some models with different ducts just to see...

[boputnam]

Hey, TD...

Sorry to be so lethargic on this, but with the NYE noise, it was hard to get any PC time.

Anyway, I corroborated what Rodd got, and then ran a model letting BBPro suggest Fb - this result (attached) suggests you lengthen the duct to 6.63-in. I can't see a great difference in the two plots, but if you're game, you might fashion a duct insert and lengthen the port to 6.63 and "see" if you notice any difference. Giskard has walked me through some "suggest Fb" runs, and the results in those cases were improved.

Lemme know!

[GordonW]

I completely agree with the sentiment of BBPro, and in fact, I'd be inclined to start with a port length of about 7 or 8 inches, and work back from there. It's easy to cut small lengths off, if the bass is weak. I'm guessing, that with a port of around 7.5 inches, the bit of peaking in the bass response in the 50-100 Hz range, will be reduced. Audibly, this should correspond to a reduction in boominess...

Regards,
Gordon.

[Roddyama]

Originally posted by boputnam
Giskard has walked me through some "suggest Fb" runs, and the results in those cases were improved.

Just a caution about moving fb to low as you start to run into the excursion limits of the 10" driver. It will work fine for lower listing levels, and you may get a little bit of bass extension, but the bass output will not be able to keep up with the SPL capabilities of the mid and tweeter.

[Triumph Don]

Thanks Guys! Just bought some thinwall "smooth" PVC that can be cut to size [length]. Now all we need is some woofers. Anybody help w/ info on the LE 111 A? [ebay # 3069341060] Strange looking cone material to me. Will keep you posted on this project, thanks again. By the way-any Rap reproduced through these speakers by the 14 yr old, they WILL take flight!

[GordonW]

Well, in response to Rodd's concerns... I'd be worried, if we were going significantly below the WOOFER's own resonance. However, with a 7.5" long port, it still should be at or above 30 Hz, which is the LE10's resonance itself. Shouldn't be much unloading problems, or bass over-excursion issues there, IME.

Regards,
Gordon.