Solid State amp for High-Efficiency Speakers

[andrew]

I also am using Crown XLS, via RCAs. I've heard that switching over to the balanced inputs can remedy the hiss a fair bit. Just thought I'd mention that, incase you were using yours via RCA. I'm planning to try an ART Cleanbox pro for the XLR 4v connection to see is the minor hiss is helped, also supposed to be a nice bump in headroom with the higher voltage input.

I’m using XLR connections. Let me know, though, how things go with the ART Clean box.

 

[Elgrosso]

If you can afford the benchmark or two la90 that would probably the best.
Otherwise what about the schiit gjallahorn? Neat little blocks, 30w in mono at 8ohms.
Distortion is not at purify level but pretty close at low wattage.
No heat, nor any noise though high sensitivity drivers on mine, but transformer hum (other owners don’t have that apparently).

 

[andrew]

All this has got me thinking about managing gain across the system (as right now there is too much gain in mid-bass and horn sections).

What, if any, impact is there on amp performance in using on-board gain (level) controls to reduce gain? I get that this reduces amplification of upstream noise (as well as noise from the amplifier itself) but does it also impact SNR or distortion?

Or, put differently, with an amp like Crown XLS1503 or Nad C298, is there any downside in using the on-board gain control to level match in an active setup?

 

[anmpr1]

So, basically, I’m after advice on an amp for a high-efficiency (~100dB/W/m) horn with a nominal 8 Ohm impedance. The mandatory requirements are that the amp has no noise and isn’t a heat machine.

My main speakers are about 101dB/watt/meter horns (Akinson Stereophile measurements). They play as loud as you'll want with a 15 watt per side 6V6 push pull, but may produce hiss/amp noise up close, along with higher THD.

With an AHB2 there is no hiss or other noise, and heatsinks never get more than possibly above room temperature. Although the speakers are rated as 8 ohm, they dip from 4 and rise to 20 ohms, according to John. Sound is very clean, to my ears.