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View Full Version : Tuning help for 2203H in L65



gasfan
01-15-2016, 02:25 PM
Okay so I want to try my newly rescued 2203H in my L65s. They fit but I can only use two screws, however with 1/4" soft foam gaskets they seem quite firmly planted. Problem is, outside of crossover issues, I just can't get my head around optimizing tuning frequency. Volume of the cabs is around 2.3cu. ft.? existing port is 2 13/16 inches ID. Calculators say around 13" for tuning frequency of 20hz. But where do T/S parameters enter the mix? And how do I determine best tuning frequency for this cab/room? Fs is 16hz. Is 20 hz too low? Either for the driver or the room? So far they sound quite good in terms of extension but not quite as loud as the 122A. Most appreciated:)

Btw, I also subbed in 104H-3

gasfan
01-16-2016, 07:16 AM
I've read a few that even I would consider stupid:bouncy:

Earl K
01-16-2016, 03:47 PM
TS = Theile/Small Parameters (https://en.wikipedia.org/wiki/Thiele/Small)

One can predict bass performance of a transducer operating within a box, once one has accurate TS parameters for their transducer ( woofer ) and a box simming bit of software ( such as WinISD (http://www.linearteam.dk/?pageid=winisdpro) ).

:)

ps ; You need to measure your refurbished woofers to get their TS parameters before you can accurately predict their bass extension ( ie; when they are used in your L65's ) .

I don't doubt that you may have changed the stock 2203H parameters by over-tightening ( reducing ) the spider's compliance.

There's a sticky located in one of the many sub-forums, on how to measure TS parameters ( using a minimum of gear ) .
- I'll let you search out that sticky .

gasfan
01-16-2016, 06:07 PM
Thank you Earl. I thought I may have increased compliance with the acetone. This is just for a fun experiment to confirm the 2203s are functioning as they should. Discovering Fs should be an easy task. I don't know how I could have changed other specs. If they are correct, the L65 cabs will need around a 6.5" stock dia. duct for a tuning frequency of 26hz with the 2203s. I haven't measured the length of the stock duct but I think I've already discovered the L65 crossover has a bigger influence on their performance at this stage. I'm not up for altering the crossovers.

Incidentally, I couldn't open the WinISD file for some reason I can't figure out. Computer utility is not a strong suit here.

kelossus
01-16-2016, 06:46 PM
In the process of building stereo subwoofers with my 2203H's to pair with L212's.

I went with 4313b's suggestion and am tuning the 2.8cubic ft enclosures to 30hz.

I imagine you would need some crossover modification as the 2203 has no chance of playing up to 1khz. In my 4315B's the 300hz it was tasked with was a stretch and was much improved once the crossover was modified to 100hz.

Unsure how low the LE5 can be crossed over but thats something to look into.