Wharfedale W70E resto- Anyone have crossover wiring info for 4uf, 6uf, 8uf version?

[Sam08861]

Hello All,

Acquired a pair or W70Es and in the process of rehabbing them. All drivers working and the purple dome tweeters (square backs, plactic covers on front) have been replaced with dayton 1" silk dome shielded tweeters. The original tweeters were provided, but one has dome that needs to be glued back and looks like one of the leads to the voice coil is broken. Will deal with that later if the replacements don't sound good.

As is, they sound OK, but the voicing is all off. None of that 'breath of life' I've experienced with the W60D Mk II (should have never sold these) or earlier W70 'a' with all alnico and the super 3 tweeter, though that ported model never sounded quite as good.

The prior owner replaced the crossovers with some generic crossovers from parts express that cross at 800hz and 4000hz, whereas the stock configuration is 600 and 5000hz, effectively squeezing the middle frequency duty from the mid driver.

I am hoping the above is why the voicing is off.

Luckily, the OP left the stock crossovers intact, but either desoldered or completely cut off the leads going to the stock crossover. As a result, I cant tell which driver leads attach where

Anyone with a W70E model have a picture / schematic or other with regard to the connection points?

Glad to post some pictures, if that helps.

 

[Sam08861]

Some more information...

The 2nd crossover had some small leads that were clipped, leading me to be able to figure some of these out.

I can see where the woofer and tweeter positives go, but not the Mids.

Also, I found 2 flying leads for the grounds, but not sure which drivers connect where. The one with the green arrow in the center, I'm not sure about, since there's no flying lead, so just a guess.

Anyone who knows crossover topology able to deduce where the negative leads go for each driver and where the positive for the midrange driver might go?

Caps will be replaced. I'm ordering both the NP electrolytics and the yellow film caps from dayton/PE, since it's only an extra $5 to try out both types. Any suggestions appreciated here as well.

 

[Sam08861]

Looking at a few other photos online, my best guess is as follows:



this gives a circuit that looks like the below: Is that a plausible circuit to get crossover frequencies at 600 hz and 5 Khz?

 

[timmatt]

Just spotted this thread. I purchased a pair of W70e's in 1971 & they are still loved. I now have three pairs.
These speakers are often under-appreciated, I think they sell cheaper than they should because they are too big to ship economically. Often see them go for under $200, always local pickup only... The W60e's always go for more - they can be shipped.
Four screws to pull the woofer and get a picture of one of the older style crossovers.
Your diagram is not correct according how mine is wired. Where is the purple inductor? I'll need to stare at this for a few minutes...

 

[Sam08861]

Hey timmatt, I ended up getting sorted out over at the DIY forum, and yep, that diagram is incorrect.

Thanks for looking into this though.

Sam

 

[timmatt]

Ok - glad you got it sorted out. Here's my drawing in case anyone comes here with a similar issue.