Low cost BL mini horn with Visaton FR10

[widowmaker]

Speaker: Visaton FR10 8ohms
Volume: 35 liters

[widowmaker]

some pictures:
1.

[widowmaker]

2.

[moray james]

The multiple folds should keep mid range frequencies from reaching the mouth. Nice size horn. How does it sound and where does it roll off? Regards Moray James.

[widowmaker]

They sounds nice and have good bass - 45-50Hz

[moray james]

for such a tiny driver. Have you considered a version with the mouth on the rear side of the cabinet? This further directs any midrange from the horm mouth away from the listener and also directs the lowest frequencies into the corners or side wall for greater coupling. How high up into the midrange do you think is escaping the horn mouth? Regards Moray James.

[widowmaker]

I tested horns with sweep signal, probably there is no response above 250Hz from the mouth...

[seanzozo]

Doing a very rough simulation with Hornresp (i.e. factory specs and exponential approx from throat to mouth, no folds)

it predicts (eyeball approximation)
55hz to 250hz -3db
and
50hz to 350hz -10db

seems fairly close to your actual measurements.

Good job.

The only thing I would note is that in a baffle that is only 5 inches wide the bafflestep should be around 900hz. Thus you will likely have a shallow dip from 350 to 900. A suprabaffle of about 12 inches should level this out if you want to try it.

Sean

[AndrewT]

Hi,
your BLH has turned out well.
What T/S data have you got on the driver?

[moray james]

horns start to become efficient at 1/2 WL. Your horn design is 1.5 metres long which is about a 1/4 metre short of 1/2 WL. If you turn your cabinet design around so the mouth faces backwards and then place the driver on the top firing forwards using a very small cavity you can then extend the horn back from the driver at a downward angle into the section that currently holds the driver. This will give you more than enough extra length to exceed 1.77m (1/2 WL of 97 Hz). You would of course need to reposition the other sections to correct for the new length and expansion but your basic configuration is preserved. The overall length is increased and the driver fires forward and the mouth backwards. Any mid frequencies now vent to the wall behind the driver not the listener. The physical height of the driver is now in line with ear level at seating position so you no longer have to tilt the cabinets up as in your pictures. Further you gain some extra folds in the horn which should further reduce midrange output from the mouth. What do you think? Regards Moray James.
PS this is an exponential expansion, yes?