Another proac 2.5 clone project!

[supernet]

Here are my pics about this speaker project, which sound such beautifull as it looks like. 🙂 The best thing is, that you can not stop listen this speakers. If anybody got some question, just go ahead.

 

[cowanrg]

what was the approximate total cost of this project?

 

[supernet]

Scan-speak bass driver and QED Qudos internal speaker cable:

 

[supernet]

About 500 Euro in my country.

 

[dshortt9]

What amp are you using and which crossover values? Did you use the notch filter?

 

[supernet]

I used Jacq crossover with notch filter. Coils are custom made, resistors are MOX and caps are Intertechnik Audyn plus.

My sistem:

NAD C541i
Musical Fidelity X-pre preamplifier
Super Leach amplifier ( a little too powerfull)

 

[supernet]

My place

 

[konstantin]

The details please.

Hi,

Can you send me the details of the project (drawings,parts,crossover,etc.)
I was allways wanted a pair of these beauties.


Thanks

 

[supernet]

Here is the link:

www.geocities.com/diyproac25

 

[JC Fardo]

Great job Supernet.

Could you pls inform your room dimensions and speakers placement. This is due some comments about bass conflicts of that clone in smaler rooms (25 square meter)

In advance thanks for comments

JC

 

[supernet]

My room (on the picture) is 4.5m×5.5m ×2.4m . In position on the picture there is no boom bass, although one speaker is in the corner. There maybe be any improvement, but space and furniture limit speakers position.

 

[Alain]

How much damping material

I have seen quite a few pictures of ProAc clones. Some seem to have very few damping (I would say about 3cm). Others like the pictures on this thread seem to have quite a bit. Is it very important to stay to specs of 5cm of damping? Is density of the material important? What would be the sonic differences.

 

[supernet]

Very important is to put bitumen damping on the walls. For lining I used 200 g / m2 ( I do not what is the name of this white stuff). There is no significant sound improvement, if you use 200g or 300g.

 

[Alain]

Cross-Over modifications

Supernet,

I suppose that you used the notch filter of Troels. Which version did you use. His latest posted on in Dec (v4) or the version of October (v2)? I listen mostly to classical myself and I like a very neutral sound.

 

[supernet]

I use series 1.5 mH + 10 ohm + 3.3 uF. With sound I am very pleased, specially with some jazz CD. But you should got at least 60-80W per channel.

 

[Saci]

bitumen

Hi,

I am building my ProAc clones, and I am planning to use roof insulation kind of bitumen plates, something like this.

I heard that "ordinary" bitumen can emit gases which can damage the speakers. Is that a big threat for me? Should I use something else instead?

Regards,

Saci

 

[Jadde]

Nice work!

http://w1.605.telia.com/~u60516421/index.htm (swe)

 

[pinkmouse]

Re: bitumen

Hi,
I heard that "ordinary" bitumen can emit gases which can damage the speakers. Is that a big threat for me? Should I use something else instead?

Hi Saci

Yes, the bitumen may outgass solvents that could affect your drivers.

What I have done in the past was to install the bitumen sheeting and do any final staining/painting/varnishing, and then move the speakers into a warm room for a few days. When you can no longer smell any solvents, then you should be able to install drivers and crossovers. The bitumen will continue to outgass for a while, but as you have a ported box it will not build up into dangerous levels, especially if you keep running the speakers, as the airflow through the port will ventilate the box quite nicely.

The emited solvents are heavier than air, so will tend to collect in the bottom of the box as well, so if your drivers are at the top, and the ports at the bottom, you should have no problems at all😉