Mid Bass Horn Design 80-800 Hz

[Steve Mac]

Originally posted by selmerdave:
Hmm, I have no hiss whatsoever in my active setup. Is it possible it's part of the high power tradeoff?

Dave

<font size="2" face="Verdana, Helvetica, sans-serif">What's yer system? If the sensitivity of the horns were 3 or 6dB less...it might be completely silent. I've got 808-8a's in 511s being fed by an amplifier with no input attenuation that supplies 180 watts who gets its input from the behringer dcx2496. But the point is if I unplug the input to the amp...it is dead quiet. The hiss...and I've heard others on the diyaudio forum talk about hiss on this unit, have recommended an analog knob for what I am facing, which is maximizing resolution and lowering the analog output signal to increase s/n. I know I'm going after a very slight hiss, but the thing is, if I make it dead quiet...this system becomes the re-amping system from **** ...which I dearly want to take advantage of in the studio.

[selmerdave]

Hi Steve,

I'm running 604's with mostly vintage tube stuff (10w/ch lows and 2w/ch highs) and a Rane AC-22B XO. No hiss audible from 2 inches in front of the drivers. It will be interesting to hear what you find.

Dave

<font color="#FFFFFF" size="1">[ September 02, 2008 05:43 PM: Message edited by: selmerdave ]</font>

[bfish]

i expect you're right Dave, tho I've never tried the low wattage route to say for sure. My ROT is to have 1.5-2 times the rated power available for the intended BW of each driver, so for even a Pascalite 900 driver crossed above 4kHz, that's 75-150W each, and even more down below, often a lot more (the 4-way I'm tinkering with has 900W/ch available). All that just so those few brief 115-120dB transients can snap thru clean, clear, and unclipped. 98% of the time, everything's more or less loafing along and staying cool.

With some amps, you could hear faint hiss from the listening position between cuts, with others you have to put your ear to the horn. It bothers me more knowing it's there than it does hearing it, but it's a tradeoff I'm obviously willing to live with.

[valhallax]

i get a lil hiss as well, mostly during warm up , but then fades as listening goes on..or i just get used to it. a band i know, the sovtek tube amp hums like crazy..the guitarists says.."thats how i know its working" at any rate its not there during program material and barely there after warm up. bfish's idea of signal-noise ratio all but cured mine.