I'm using the A-100 amp with my 25 ohm Denon AH-D5000 phones with the jumpers in presently. Should I be using this amp in the high power configuration with these 25 ohm phones? Would I get better response and sound with the lower power configuration? Thanks, Sam
Well honestly at 25 ohms, switching to high power gives you a bit over 12000 mwatts of power for your headphones. Which is INSANE. At this power, unless it's a headphone like those planar magnetic headphones like the hifiman's, you may find that you have very little play in the volume control and you may even damage it by giving it too much power. Even 4 milliwatts of power should get you to quite loud volume. You also may get too much hiss so I'm going to say you'd probably prefer the convenience of the jumpers in. But you can try it, just be real careful with the volume control.
Transport: Sony UBP-X700 UHD-Blu ray player spdif PC using Musiland Digital Times WASAPI via BNC connection - DAC: DC-1->XLR XPA-1 , RCA->Basx A-100 CD: Denon DCD 600 PCM 61 DAC. RCA Amp: XPA-1 gen 2 using XLR connections. Speakers: Axiom Audio m80 V3, Sennheisser HD700 headphones. two pairs 12 guage each bi-wire speaker cables per monoblock Headphone amp: Basx A-100 (INCREDIBLE VALUE!!)
When I bought the BasX I was using HiFiMan HE-400's so I put the jumpers in and they sounded great with all that power. Those cans are really hard to drive. When I got the Lawton modded Denons I tried them with the same setup and they really jumped out with the high power but there's very little volume control and I get the left channel drop out until it's turned up past it. They sound a bit harsh at volume so I'm obviously over driving them. I went ahead and pulled the jumpers for the Denons as I don't really use the HiFiMan phones anymore. The Denons are far better headphones IMHO. Much more top end and tighter bass, the HiFiMans have a ton of midrange but are lacking a bit everywhere else. I'll try the Denons like this for a while and see if I like this setup better. After listening for a while I'm putting the jumpers back in. I lost a lot of inner detail and bass with it in the lower power configuration. I'll just have to be careful with the volume knob.
Last Edit: Feb 4, 2020 17:41:05 GMT -5 by slovell: update
The Bas-x A100 is for showing high impedance headphones whose boss! Beyer Dynamics, Senns, Stubborn Planars etc. If you have a 32 ohm easy peasy drive, just leave the jumpers in and enjoy. You could go full bore but the noise floor at least to me is objectionable. But 600ohm or 250ohm, rock on and ditch the jumpers.