Re-Built Vifa Basis 95 -> 2023

[motokok]

Is 3L for the D75 the optimal volume? What was the original? I thought the datasheets said 1L or so.

 

[Hondasnl]

Hi ;-) I made a little bit smaller.

 

[profiguy]

Is 3L for the D75 the optimal volume? What was the original? I thought the datasheets said 1L or so.

It depends on how far down you want to run it, but anything from 1 to 3 liters is good, depending on how much dampening material you want to use. The main result you want to see is a reduction in Qtc through overdamping the dome. You want to be under 0.9 Qtc.

There are 7 little holes in the rear middle pole plate covered with felt. Thats the only open area which needs chambering. Removal of the felt helps, but you have to make sure no particles get into the motor when its opened up.

 

[mterbekke]

To get an idea of where and how much dampening you need for the bass section, it helps if you stick your head through 1 of the holes and use your voice to hear what happens when your hand moves the material in the box through the other hole.
Best is to not get it on the walls, but try to get it stable in the middle of the space. If the material allows it. Add more or less, untill your voice stops ringing, echoing, but not so much as to make it dead inside.

Nice project and I see you're having fun. All that matters.

 

[Stanislav]

D75 is a dome mid, right?
As such it doesn't need any separate volume, can live happily in the main volume. It's xover slope and cut off point needs to be determined by the xover, so no extra help from physical means.
One reason I don't like dome mods, plus their Fs is always way higher than desired.

 

[Hondasnl]

To get an idea of where and how much dampening you need for the bass section, it helps if you stick your head through 1 of the holes and use your voice to hear what happens when your hand moves the material in the box through the other hole.
Best is to not get it on the walls, but try to get it stable in the middle of the space. If the material allows it. Add more or less, untill your voice stops ringing, echoing, but not so much as to make it dead inside.

Nice project and I see you're having fun. All that matters.

Yes I know that trick 🙂 .

 

[profiguy]

D75 is a dome mid, right?
As such it doesn't need any separate volume, can live happily in the main volume. It's xover slope and cut off point needs to be determined by the xover, so no extra help from physical means.
One reason I don't like dome mods, plus their Fs is always way higher than desired.

This D75MX41 dome is vented in back of the motor and requires a separate chamber. It has a pretty solid reputation, which is why its still in production today. Its my favorite dome mid for multiple reasons. No, you can't cross it that low, but it makes up for it in performance.

 

[Hondasnl]

I do like each driver in separate cabinet. It's the best solution!

 

[Stanislav]

Yes, you are right. I read a bit about it just now, a newer version of the old vifa dome mid. Apparently great as an OB mid above 1kHz once the felt is removed.

 

[motokok]

What does the felt even do? And when is @profiguy going to finish his D7608 how to use article! 🤣

 

[profiguy]

I'm still working on a potential WG for the D7608. I've had some setbacks with health slowing me down. Hopefully should have something soon.

 

[Hondasnl]

Received all components for rebuilding the new separated crossovers.

Nice parts for the speaker 😍😍.

 

[Hondasnl]

In progress, the different filter sections.

 

[Hondasnl]

Me love it 😍 .

 

[motokok]

Nice rug!

What are these perforated crossover boards? They look pretty nice.

 

[Hondasnl]

A little step further.
Filters are ready with the cabling.
Waiting for the wood 😀 .

 

[Hondasnl]

The sawn wooden panels have now arrived.
However, the sawmill made a mistake and that is that the panels are 27mm thick instead of 19mm thick.
I don't think that's a bad thing of course 😍😍.
And that for the same price.😎

Drawings need to be adjusted again.

So we can get started.
Start with the compound thick baffle.

 

[Hondasnl]

Very very happy with the gaps between drivers and baffle.
I have nevertheless chosen not to sink the woofers up to the second panel.

At the woofers and mids later self-adhesive sealing tape in between.
It goes very well and very happy with the results.
This is going to be a beauty 😍😍

 

[Hondasnl]

Some little progress 😀 .

 

[Hondasnl]

And the facets applied.
Perfect and tight!