Crossovers and which Inductor is right?

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- Anyone have an opinion on which which crossover is the one they would try?
Let's look at the two crossover suggestions side by side. Nope, looks like six and half a dozen to me!

However, you already know my opinion - go minimalist, as Wharfedale did! ;)
 

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--- There are several other Mods I would like to try to try and see if these W70's can be improved upon or not ... It turns out that Wharfedale had major fire a while back, so a lot of information was lost regarding most of their past speaker designs, so one of the guys on another forum had the drivers sent to someone who measured all the the Thiele-Small Parameters on the drivers for this speaker. One of the things that they came up with was that for some reason - probably marketing , they made the speaker box a lot smaller than it maybe should have been - the speaker box appears not really to be optimized for the 12 inch Alnico Bass driver. The W70 has approximately 4782 cubic inches inside - the bass driver really needs at least 5 cubic feet or more - that's 8640 cubic inches, pretty big difference! ...
- The other issue that might make a difference is that there is no separation between the 8 inch Midrange and the bass driver, it seems like the woofer could be muddying up the sound of the Midrange driver some - so another thing I would like to try is build a temporary box to put around the Midrange and see if it would improve the sound quality of the Mids any or not , if not it's will be easy to change things back. But that box will also be taking away more of the space that the Bass driver needs. One option is to build a bigger speaker box, but it would be hard for me to make grill design look as good as the production grill and WAF and resale wouldn't be optimized either - LOL. So another option is to extend the back of the box , but that is like doubling the depth of the cabinet... Also not exactly WAF - or resale optimized.
One idea I'm thinking of trying is I managed to get a screaming deal on a second pair of the 12 inch Alnico Bass drivers to see if turning the box into a kind of Isobaric design would more optimize the Bass..... the idea is to cut a hole in the back of the speaker cabinet that the second bass driver can be attached to, leaving the back of the second driver is sticking out the back, (it would be easy to make a small cover for the portion of the driver sticking out the back) ... I read somewhere that doing that would make the 1st driver think and preform like it's in a larger box than it is without having to actually to put it in a larger box........... A complication is that the back wall of the current speaker cabinet is not removable and is actually a double wall with sand between the two layers.... so a hassle and making it hard to put humpty dumpty back together again if my idea doesn't help much. I could whip up a second set of speaker cabinets, just to try the idea and see if it works, then it would be worth the effort to make the changes to the original cabinets. ------- So , am I off my rocker or not?
 
Hi Galu , I am cursed with wanting the best sound and having little money . . . . but if all goes well and the W70 does live up to my hopes. The drivers that the SFB-3 utilizes are a little different and Better than the W70's . So after short test to see that the W70 is "All that and a bag of chips" , or at least that's the battle plan.... then I want to sell it - in it's Refinished / restored/and maybe slightly modded form. Then I can collect the drivers needed to Replicate the SFB-3 -- of coarse they aren't inexpensive , but less than an original SFB-3. Then choosing which version of the SFB-3's I like the looks of best, I can build it exactly as i want it to look -- and of coarse with just a couple mods --

Best Regards,
Dean
 
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DIY is like this. The answers to some of your questions may already be known. Your crossover suggestions are coming without knowing why they will make a difference.

For example, consider a woofer that performs best under a certain frequency. What frequencies can and can't be used, how far should the top be cut, how should it be done to keep the overall result smooth.
 
--------------------- Hi Allen , yes I do kinda understand that , but I hoped to get lucky and either find someone who had experience with the Speaker/crossover , or find a speaker Guru that could give some of the answers I was looking for ... I know that some of the question are, try it and see. But I did get some of my main questions about the crossover parts answered - and that will Help a Lot!
- The problem of which of the two crossover would be best to try is important because I don't have enough to buy the parts for both crossovers to try and see which sounds best. It will cost around a hundred fifty with having to add 4 L-Pads to the bill for crossover parts, if it was just me I would probably just find the right resisters and forget the L-Pads, but I want to keep the L-pads in the speaker for resale and to make it easier for the next person who owns them. I know that isn't a lot of money but we've been on disability for a long time -- so It's a good year if I can save two to three hundred in a year - I'm not complaining at all, many are far worse off - just trying to use my money as wisely as I can - :)
- Since these speakers are stepping stones to the vintage speakers I really want, I need to at least get close to breaking even when I sell them.. I need to be able to afford to buy the drivers for the dream speakers, and if I put another two or three hundred into them I won't break even and may not be able to afford all the parts to build the ones want this year.... So far I have REALLY Liked these W70's and with some new parts they should get nothing but better!

- As far as the idea to try and use the isobaric configuration - I have no idea if that will work very well or not. I read some information about using the second woofer in it's own compartment in the box to support the first woofer giving it more optimal conditions to operate in, and that it does work. But I found there are arguments against it. The main one is that by the time you add the second woofer and give it enough space to work correctly, ( to make the first driver think it's in a bigger box than it is ), you are just about at the same place you would be if you just gave the first woofer the correct amount of room in the speaker box in the first place. But because I don't want to double the size of the box, or even build a new box at all if I can help it - (better for resale if it's not a small refrigerator - LOL) - I want to try the idea I found of making it the kind of Isobaric configuration where the second driver is mounted to the inside the back wall with just 5 or six inches of that driver's backside sticking outside the box. I just haven't found anything more than a few diagrams of two woofers set up that way, I don't know of any speakers like that, and I haven't been able to find any threads where it is discussed - that's why I was hoping to find someone had tried it or someone who knew anything about the idea. --

Best Regards,
Dean
 
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diyAudio Moderator
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Interesting, as putting the speakers face to face like that could simplify the concern over their coupling. On the other hand you now listen from the back of the driver.

Bottom line, face to face they are simpler to attach to a piece of wood. Not sure how high they'll work without testing.
but I hoped to get lucky and either find someone who had experience with the Speaker/crossover , or find a speaker Guru that could give some of the answers I was looking for ... I know that some of the question are, try it and see.
It's not for want of trying, it's very difficult to guess. This is also a complex baffle arrangement.

Four options..
Someone who has a set and has learned the driver acoustics and found a good cross.
Someone who knows an old thread where this happened.
Get a microphone and equalise what you see until you like it sufficiently *
Measure and cross to your own level of satisfaction.

* In addition to this, you can post your equaliser result here and driver impedance curves and we can back-convert it to passive.
 
Since you bring it up, Dean, let's examine the financial aspect further.

These speakers may be regarded as a piece of industrial archeaology. They are valued for their vintage sound.

Any modification, other than replacing like for like, will devalue these speakers in the eyes of a Wharfedale enthusiast. Furthermore, interfering with the cabinet and its sand-filled back would simply be anathema!

If you really want to recover the money you paid for them, then caw canny, as we say in Scotland! ;)

(Caw canny - proceed warily)
 
You may want to get an LCR meter and measure the value of each component of the original crossover, that way you can pretty much reproduce it with new components (while you're at it measure the new values too). Older components had tolerances of +/- 10 or 20% (unless they happened to have been selected or matched between speaker pairs) and in addition those values may have changed over time, so two "identical" speakers could sound slightly different, not even counting variations in drivers.
 
- Hi Galu, I have been thinking for awhile about the aspect that you mentioned about keeping the Wharfedale W70's as close to stock as possible for their historical value and for resale . . . . For the crossover it would be easy to make two crossover boards one that uses the original component values but new parts, and then the second board with the new modern style crossover. To simplify things a little both would have their own wiring harness too , that way the customer/buyer could have the option of which crossover he would like to use and it would be just a few solder connections and your choice is up and running, after I find out the buyers preference I would solder it in... I could also include both in the sale -- :) --
- I'm now thinking I want to do the same for the original sand filled back. First I make a second back for the speaker with the cut outs for the second woofer... I will also make it so it will be sand filled just as the original back was. -------- Then I would Carefully cut the original back panel off with the sand intact , clean up the edges then add an inner lip to that back piece and a gasket so it can be screwed back in place for resale if necessary. I would also make a frame to be screwed / glued to the inside of the speaker cabinet that will keep the cabinets from flexing now that the back is not a solid part of the box ,and also so the back panel would have something solid to but up to. --- I could also add brass screw inserts so either back panel can be screwed on and get a good tight seal.
- In fact, the way the manufacturer set things up is, that at the moment to get in to do anything with the drivers or crossover you have to unscrew the front of the cabinet which the drivers are screwed to, so I'm thinking I should maybe add brass screw inserts and a gasket to the already removable front piece too.

Best Regards,
Dean
 
Just some historical information for interest:

Wharfedale Audio Products produced 'Americanised' versions of the UK cabinet systems of increasing degrees of differentiation. The Wharfedale W70 had no UK equivalent and was created exclusively for the US market. All the components were supplied from the UK, but the furniture-styled cabinets were locally sourced and the systems assembled at Port Washington, Long Island. (Information from 'A Pair of Wharfedales' by David Briggs.)

Now, if your Wharfedale was a UK model, I'd be much more upset over you modifying it! :D
 
Ok hallcon ,remember on this vintage speaker , TODAYS modern deep bass is not going to be its strenth .but it can tuned down some (to remove some of the massive midrange this speaker makes)...YOU may need a seprate SUB. .. mine had the 10in mid and i used the one pot the control IT.
 
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