BIC Venturi Formula 4 recap and restoration

[JayPare]

Got it:
http://foamspeakergrilles.com/

Get a hold of sonofagun Bob Shafer in Evart MI
spellings might be off a bit, but he's the one who made these:

 

[JayPare]

Capacitance adds together when you wire 2 or more capacitors in parallel. So, you could get 2 8uf caps, or add a 1uf to the 15uf. If you want to keep it simple, it's fine to buy a single 16uf cap, but Mundorf E-Caps are very good.

I know it's been a long time but time is rare these days. I'm currently placing my order for caps and I wonder if I should replace the film and the electrolytic capacitor with the Mundford ecap of only the electrolytic and get film from Mundford for the film one. If you recommend the later, there seems to have a bunch of different film capacitor for those caps:



Which one would tou recommend? Thanks again!

 

[toxcrusadr]

I would stick with film where the manuf. put film.

I don't know the Mundorf lines worth jack so this comment is a general one. If you click on any of the individual caps at Parts Connexion (and probably at Mundorf too) you can find a pdf sheet about that line. It will tell you a few things about the construction mixed with some flowery language about its benefits (not picking on Mundorf, everyone does that).

Also, look at the cost in comparison to where your speakers sit in the vast continuum of audio quality. Not junk, not very expensive high end, but somewhere in between. You probably want to spend an amount commensurate with that. Maybe (maybe!) the super high end expensive caps do have improvements over cheaper ones, but chances are if the speakers can't resolve those tiny differences, you're not going to hear them anyway. Kind of like putting racing tires on a Chevette. I probably wouldn't spend $69 on a cap for a speaker that's worth a couple hundred, for example. But I might spend $10 if I really like the speakers.

Someone will hopefully come along and recommend which of these 14 types of caps is good. You can also search AK for "Mundorf" and see what people are using.

 

[toxcrusadr]

Actually here's a better link. I like the way they have this laid out: a full description AND prices together for each type.

http://www.mundorf.com/en/?category=hifi&menu=caps_audio&content=mcap

They're laid out in price order on the list at the left. The cheapest 1 uf is the MCap ($2.79), middle of the line MCap Supreme is $14.90, and the SilverGold Oil is - haha this is funny - $69. I swear I didn't look at that till after I posted the above, which was just pulled out of the air.

Also there are some lines like the EVO that are only offered in limited values (all <1 uf) so that may eliminate some entire lines from consideration.

 

[StimpyWan]

I know it's been a long time but time is rare these days. I'm currently placing my order for caps and I wonder if I should replace the film and the electrolytic capacitor with the Mundford ecap of only the electrolytic and get film from Mundford for the film one. If you recommend the later, there seems to have a bunch of different film capacitor for those caps:

View attachment 1360225

Which one would tou recommend? Thanks again!

I've mainly used Mundorf EVO Oil caps. MKP's, and E-Caps as well. I think any combination would be worth your time and money. MKP or EVO Oils for your film caps, and E-caps for the electrolytics. All good, but the EVO Oils are very good. Clean and open.

 

[JayPare]

@StimpyWan and @toxcrusadr, approved?



15µF + 1µF electrolytic to replace my 16µF electrolytic,
4.7µF electrolytic to replace my 4.7µF electrolytic
0.47µF film to replace my 0.5µF film
1µF film to replace my 1µf film

 

[StimpyWan]

@StimpyWan and @toxcrusadr, approved?

View attachment 1360304

15µF + 1µF electrolytic to replace my 16µF electrolytic,
4.7µF electrolytic to replace my 4.7µF electrolytic
0.47µF film to replace my 0.5µF film
1µF film to replace my 1µf film

That looks good. But, a word of warning; the EVO Oils are large capacitors. Check their dimensions, to be sure they'll fit your crossover board. If too big, maybe step back to the MKP's. A nice, dynamic capacitor, that's a bit smaller, due to their lower voltages.

 

[JayPare]

That looks good. But, a word of warning; the EVO Oils are large capacitors. Check their dimensions, to be sure they'll fit your crossover board. If too big, maybe step back to the MKP's. A nice, dynamic capacitor, that's a bit smaller, due to their lower voltages.

I'm doing a brand new PCB for them! I will proceed with this! Thank you very much for your inputs guys!

 

[JayPare]

New PCB with brand new caps:



Still need to solder everything and add the inductor coils.

 

[borus]

Before you go any farther look hear http://troelsgravesen.dk/coils.htm. I need to zoom in to see the photos.
Scroll down to see a diagram.

 

[JayPare]

Before you go any farther look hear http://troelsgravesen.dk/coils.htm. I need to zoom in to see the photos.
Scroll down to see a diagram.

What if I have 3?

 

[toxcrusadr]

3 inductors? They can each point in a different dimension.

Also they can be the same direction as long as they are not too close. And avoid poking a nearby one with the axis of an inductor. i.e. 4 and 5 in the linked diagram are bad but 6 and 7 are OK.

 

[toxcrusadr]

Note also that a lot of crossovers are made with 'bad' alignments that seem to sound fine. It's best practice to do it right though.

 

[JayPare]

What do you guys think?

 

[RTally]

What do you guys think?
View attachment 1371311

Good job orienting the inductors to avoid cross-coupling.

That looks like a hex head bolt holding down the inductor in the upper-left. Don't do that. The bolt will act as a core and change the inductance of the coil. It would be better to use tie-wraps to hold it in place, similar to what was done for the others. If you feel it must be bolted down, use a nylon bolt.

 

[JayPare]

Ok I will tie-wrap this one too! Thanks for you input!

 

[JayPare]

Some more pictures of the front!



I covered the phenolic tweeter with this:
https://www.amazon.com/gp/product/B00114M6YM/ref=ppx_yo_dt_b_asin_title_o00__o00_s00?ie=UTF8&psc=1
You can find this at Wal-Mart, but I ordered mine from Amazon.ca.

Here is a closer shot of it:

 

[JayPare]

Before:

 

[toxcrusadr]

Lookin' good! How do they sound?

 

[JayPare]

Lookin' good! How do they sound?

Still have too listen to them I only tried them a little bit yesterday but from what I've heard for now, real good!
However, they seems to draw more current than before? Can it be? I tried to listen to them at a high level and my amp was clipping, but I'm pretty sure I was able to go that high before...