B&C Compression Driver and Horns

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Jump to Latest
col

col

Member
Joined 2008
minirig.org.au
How much eq did you had to add (at each frequency, if you have th data)?
How does this setup compare to your previous one (the one with the cheap JBL PT waveguide) ?
Click to expand...

I didn't keep the EQ profile for before the foam. So don't know about that.

The JBL 2407H (rebadged BMS 4540ND) and PT waveguides from one of my previous systems were very good. When I sold them I regretted it almost straight away. That system (http://minirig.org.au/minirig-v6/) was for a different purpose to this one though. I built that up to do parties with. It had a lot of equipment that I wouldn't use with a HiFi.

col.
 
col

col

Member
Joined 2008
minirig.org.au
Nice photos of your gear.

I see that you have both ART SLA and Crown amps in your rack. Do you have any opinions to share regarding sound quality of those units?
Click to expand...

Thanks, that system isn't the one that Iv'e been discussing in this thread. I sold that system a while back. Both the ART SLA1 and the Crown amps are very good. If you are thinking about using them in a home The SLA1 is quieter. A lot of DIYers modding it too, heaps of info on the net. The Crown is a very powerful and clean amp, it's fans are noisy though.

The amps I'm using now are better for home use. They use a lot less electricity and sound better. I have a 41hz 4 channel amp9-basic powering my mid/highs and a Hypex 2 x UcD180 powering my subs. These are both D-class.

amp9 = http://pix.minirig.org.au/main.php?g2_itemId=345
UcD180 = http://pix.minirig.org.au/main.php?g2_itemId=237

col.
 
Helmuth

Helmuth

Member
Joined 2008
gedlee said:


People keep talking the waveguide contours as if the shapes are something magical. To me at least 1/2 of the improvment in the more modern approach to waveguides IS the foam plug. Many people are using horn/waveguides now, but very few are using foam and I just find that without the foam "your not quite there".
Click to expand...


gedlee said:


I'm just guessing at how the foam will affect "other" waveguides, its likely different in every case. My point is that its a profound effect on any good waveguide. Most people seem to be missing this fact.

Last night I went to a freinds house who has an old set of JBL SR8's. I found the horn intolerably harsh and suggest that maybe some foam might help. We cut a piece and stuffed it down the horn. Better! We put a block of it on the outside where the acoustic lens was. Better yet! But there was still some residual harshness that I did not like. So, yes, foam always seems to help, but can it fix a disaster - sorry no.
Click to expand...


Hi Gedlee,

What kind of foam are you using.

And are there thd measurements off a horn with and without a faom plug.

Regards Helmuth
 
S

Sheldon

Member
Joined 2003
Helmuth said:
What kind of foam are you using.

And are there thd measurements off a horn with and without a faom plug.
Click to expand...

The foam is an open cell polyurethane like this, but cut from blocks: 86115K51 from mcmaster.com
THD is not affected by the foam. High order modes (HOM), which are reflections within the horn are suppressed.

Sheldon

edit: I'd suggest just buying the foam plugs from Dr. Geddes. Further, I'd ask for a little extra so that you can make an extension that goes right up the the phase plug of the driver.
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Top Bottom