Ping Scottmoose Bruce 1v2 Filter

[Les Hudson]

Hello Scott , I built a pair of Harveys 1v1 and was so impressed that I thought that I would try a pair of Bruce 1v2 with a pair of 206e that I had. At the moment the Harveys sound much better. The 206E/Bruce needs a correction circuit or filter. Can you please advise me on this. Here is a pic of the Harveys.

Thanks , Les Hudson

[planet10]

You can start by trying 1-4 ohms in series.

dave

[planet10]

PS: is that a set of FF85 metronomes near the wall?

dave

[Les Hudson]

Kind of , they are FF85 Truncated Pyramid Tapered Quarter Wave Pipes that I had modeled with M King software. Sound great!

[planet10]

Les,

Because it is a pyramid, the taper is actually quadratic, not linear, which does put them into the Metronome camp... cool that you came up with them independently.

Can you post size details? I'd like to put that into the Metronome database.... FF85KeN is right at the top of the list of my favorite drivers, and the Met i currently have is very short to be used as a mid-tweeter to be set on a bass cabinet.

dave

[Les Hudson]

Exterior size is 60.5" tall , 2" x 2" at the top , 5 5/8" x 5 5/8" at the bottom. Wood 3/4" thick. 5 liters internal volume. Port 1.75" dia. hole located 12" from internal bottom , 1oz. polyfill covering from top to 35" down. Driver 27.75" from internal top to driver center. I'm still experimenting with supra baffles and such.
Les Hudson

[Les Hudson]

I built a pair of Harvey 1V1 with a monocor 4" and was so impressed that I had to build a pair of Bruce 1V2/ 206E. At the moment the Harvey sounds much better than the Bruce. I need advice on a filter for the 206E. I would prefer to do this at line level between Pre-amp and SET2A3 amplifier. Thanks , Les Hudson

[planet10]

Thanx for that Les.

Note that what you need is likely not BSC but the series R i have already mentioned. Bruce was designed for FE207, and the Q of the 206 needs to be raised to make it work properly. Working properly the gain of the box is such that little or no BSC is required.

dave

BTW: Scott is quite scarce at the moment. His dad is quite ill.

[Les Hudson]

Right on , thanks

[Scottmoose]

Edit -Dave beat me to it.

V. little audio time at the moment, but the box was designed for the 207, not the 206 & can do little to compensate for the latter's rising response above ~1.5KHz. That's not step-loss, but inherent to the driver as Dave mentions above. A few ohms of series resistance as suggested might help, although you're likely to have ~equivalent of 2.5ohms already with that SET 2A3. A speaker level shelving filter would be on the lines of 4ohms paralleled with a 0.5mH inductor. Bit of toe-in might help. Line level, I wouldn't like to say, I rarely work with passive components at line level & the values, just as at speaker level, will depend on the electrical characteristics of the components at each end, in this case the pre & power amps rather than power amp & speaker.