2235 reconing for subs

[pinguin]

Dear Lansing community,

this is my first post here. But I'm not entirely new since I've already been reading along for a while. I'm not an expert on loudspeakers but I hope when getting some good advice I'll be able to do what I've been told. So please forgive me if my questions seem a bit strange for people quite familiar with this stuff.

I'm considering of building a subwofer for home use and somewhere in this forum I've read the 2235 works well. And to be shure of what you get reconing a damaged woofer shall be a good approach.

Currently there are two 2226h offered on ebay Germany - unfortunataly seperately. This is one of them:
http://cgi.ebay.de/ws/eBayISAPI.dll?...MakeTrack=true

Can you please give me some comments/advice for my project in particular concerning the following items:

Can these woofers be reconed to a 2235 or are there any alternatives?
How much is it?
I've never done something like this before. Is it very difficult?
If I can't do it by myself is there anybody in Germany/Europe providing good quality?
Which enclosure is best? Maybe this depends on the loudspeaker I want add these to: It´s a small tqwt suggested by l'audiophile in the 80ies. Efficiency is somewhat between 93 an 95 db/w/m (I can't measure this).
And this leads to my last question: Do I have to go active?

Thanks for any comments and greets
pinguin

[Guido]

Hi Pinguin and welcome!

The 2226 can't be reconed as 2235! The gap/coil structure is different.
You'll need K140, 2225, 2235 or 2234 cores. The Ferrit types are preferable.

If you need an proposal for 2225 reconed as 2235, PM me with your real name and email. I'm a JBL reconer here in germany and currently have 2 2225 cores available.

[Zilch]

http://www.lansingheritage.org/html/.../1983-subs.htm

B380 equivalent version for 2235H is near the end of the article....

[grumpy]

Jan 1990 Audio magazine has another take on a dual 2235H sub ... -huge- box, much
less often mentioned. Interesting read. -grumpy

[Zilch]

I'm not finding it online.

You have a copy, Grumpy?

[And a scanner? ]

[grumpy]

copy, yes. scanner no. I couldn't find it online either or I'd have inserted a link.
I'll try to capture the gist of it and post this evening. -grumpy

[grumpy]

First off, sorry for hijacking the thread...

Article is "Certified Bass for the Certifiable", by James S. Sherwin. Audio magazine, January 1990, Vol. 74, No 1.

From Table III - Box and system parameters

Net Internal Volume (Vb): 22.9 cu ft
Helmholtz Resonance Frequency (f1): 20.0 Hz
Box Leakage Q (Q1): 3.0
Minimum Vent Area: 169.2 cu in.
(author probably meant sq in)

author compares several vent length vs. port area (sq in) and diameter options

Tuning Ratio = H = Fb/Fs = 1.000

Alpha = Vas/Vb = 1.415

The author spends some time discussing outdoor measurements,
boundary loading, thermal vs. excursion limits, and subjective in-room
experience.

I'll be passing a copy on to a member who has volunteered to scan/post.

Cheers,

-grumpy

[Zilch]

Geez, that's the size of the 4688 TCB Monster Sub....

[Guido]

Sorry pinguin my 2225 cores are sold!

[Zilch]

Article:

[Zilch]

The rest:

[Robh3606]

Nice going Zilch we should drop that one in the Tech Library with the other sub article so it doesn't get lost.

Rob

[lucfm]

Nice going Zilch we should drop that one in the Tech Library with the other sub article so it doesn't get lost.

Rob

More information available about the James S. Sherwin stereo horn system?Particularly the bass/midbass short exponential horn and speaker design, operating from 80 to 700 Hz ?