Control = more muscle or grip over cone movement.
Resolution = More information retrieval, finer detail in the music
Eek, describing sound is not my forté. They sound great. I think the DLCP-UcD combination was also pretty fantastic (especially for the price). I think they are delivering more resolution in terms of sound (like there is slightly more on the recording) and the amps seem to output more bass, could be the filters.
Bearing in mind this is currently a media centre, most music is streaming through Spotify at 320kps, cables are cheap/freebies and at the moment L&R speakers are just twisted together from one amp to get stereo. I think with two amps, some proper playing with filters and a measurement mic and these will be fantastic. I don't want to discourage anyone from buying some...
I have a new turntable, which I will try out in the next few days and see how that works.
As for the noise, its a very faint hiss, I would guess about 4-8Khz. About the noise of the quietist whisper you could do in someones ear, almost sounds like a CD player spinning if your really close. You can't hear it 50cm away, could be microphone issues in cables on my speakers? Just checked also that the Hypex speaker cables are not crossing the amp and the SMPS build it. I just tried with a SPL meter on my iphone, ambient in the room (windows open) 37.5db, right next to the driver 39db.
I just tried turning off the Mac Pro, and the sound is still there, as well as disconnecting the optical cable.
Bearing in mind this is currently a media centre, most music is streaming through Spotify at 320kps, cables are cheap/freebies and at the moment L&R speakers are just twisted together from one amp to get stereo. I think with two amps, some proper playing with filters and a measurement mic and these will be fantastic. I don't want to discourage anyone from buying some...
I have a new turntable, which I will try out in the next few days and see how that works.
As for the noise, its a very faint hiss, I would guess about 4-8Khz. About the noise of the quietist whisper you could do in someones ear, almost sounds like a CD player spinning if your really close. You can't hear it 50cm away, could be microphone issues in cables on my speakers? Just checked also that the Hypex speaker cables are not crossing the amp and the SMPS build it. I just tried with a SPL meter on my iphone, ambient in the room (windows open) 37.5db, right next to the driver 39db.
I just tried turning off the Mac Pro, and the sound is still there, as well as disconnecting the optical cable.
So what actual physical properties (that a designer can try to optimize) of an amplifier do those descriptions correspond to? Control of cone movement (assuming sufficient power output) is pretty much a function of output impedance, but all the hypex amps are at levels way below the point where the speaker internal resistance totally dominates, and "finer detail" is a function of signal-to-noise ratio and THD (so basically THD+N), and again all hypex amps are way better than any recording out there.
That doesn't sound like oscillation, more like switching noise picked up by input wiring (as a guess).
@Julf. The units are stock and the cabling is tight, I would assume you mean switching from the SMPS. Does anyone else have theirs yet? Any similar issue?
@Audio Elite that was what I was thinking, could all simply just be me wanting to hear improvements in my system though. I was really happy with the DLCP set up. and these amps are actually less powerful 180w vs 120w. People seem to love the nCores.
One small other thing, I can't in HFD seem to change the settings on the first screen (not HFD). So at the moment its in the super low power mode, which turns it off if it doesn't see a signal for 15mins. Playing a signal through optical doesn't turn it back on, so I have to switch it off and on at the unit. There might just be a button I need to flick.
@Audio Elite that was what I was thinking, could all simply just be me wanting to hear improvements in my system though. I was really happy with the DLCP set up. and these amps are actually less powerful 180w vs 120w. People seem to love the nCores.
One small other thing, I can't in HFD seem to change the settings on the first screen (not HFD). So at the moment its in the super low power mode, which turns it off if it doesn't see a signal for 15mins. Playing a signal through optical doesn't turn it back on, so I have to switch it off and on at the unit. There might just be a button I need to flick.
I’m excited to receive these units. Mine are actually going directly to Rick Craig of Selah Audio to work on a kit which will be built around these units. It’s my first time to use an active approach to speakers. Hopefully they will ship soon!!
I got my FA252s in and got em on my bench.
0.0003% THD, 0.076% THD+N at 1 watt into 4 ohms
0.003% THD, 0.004% THD+N at 10w into 4 ohms
0.03% THD, 0.03% THD+N at 100w into 4 ohms
0.04% THD, 0.04% THD+N at 250w into 4 ohms
And noise on the bench with and without a 12db transformer pad. Volume on the amp was set at -3. No filters loaded. Pardon the pops as I was moving some connectors on the transformer.
YouTube
0.0003% THD, 0.076% THD+N at 1 watt into 4 ohms
An externally hosted image should be here but it was not working when we last tested it.
0.003% THD, 0.004% THD+N at 10w into 4 ohms
An externally hosted image should be here but it was not working when we last tested it.
0.03% THD, 0.03% THD+N at 100w into 4 ohms
An externally hosted image should be here but it was not working when we last tested it.
0.04% THD, 0.04% THD+N at 250w into 4 ohms
An externally hosted image should be here but it was not working when we last tested it.
And noise on the bench with and without a 12db transformer pad. Volume on the amp was set at -3. No filters loaded. Pardon the pops as I was moving some connectors on the transformer.
YouTube
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For using the built in measurement function can someone (@ds23 man?) remind us all what microphone is recommended and if a power supply is also required, and cables etc.
There doesn't seem to be any info in the user manual, if anyone can provide a walk through of how to do this, or point me/us to a link?
Has anyone tried the MiniDSP Dirac Live equipment in the signal path, do you think a similar room EQ can be achieved with the HFD?
There doesn't seem to be any info in the user manual, if anyone can provide a walk through of how to do this, or point me/us to a link?
Has anyone tried the MiniDSP Dirac Live equipment in the signal path, do you think a similar room EQ can be achieved with the HFD?
First of all: get a decent mic with a calibration file:
Dayton Audio EMM-6 Electret Measurement Microphone
Next is a decent usb soundcard with a balanced mic preamp: Focusrite Solo or 2i2 are decent ones.
Scarlett Range | Focusrite
The rest? Mic stand, xlr mic cable and a TRS to cinch cable.
Dayton Audio EMM-6 Electret Measurement Microphone
Next is a decent usb soundcard with a balanced mic preamp: Focusrite Solo or 2i2 are decent ones.
Scarlett Range | Focusrite
The rest? Mic stand, xlr mic cable and a TRS to cinch cable.
ugh, some of my images went missing. Re-uploaded a bunch of tests. Everything looks great except CH1 has more noise than CH2. Confirmed on multiple units.
more images here: Hypex FA252 Measurements - Album on Imgur
more images here: Hypex FA252 Measurements - Album on Imgur
okay, got both amps up and running (FA503)
what however wonders me is that one of the amps gets significantly hotter so that the fan is running. the other amp is much cooler and the fan is not on.
is that normal?
and further, one of the amps has a more noise than the other.
one is just the usual white noise if you put the ear very close to the driver.
but the other one has this high-frequent interference noise which is fluctuating.
what however wonders me is that one of the amps gets significantly hotter so that the fan is running. the other amp is much cooler and the fan is not on.
is that normal?
and further, one of the amps has a more noise than the other.
one is just the usual white noise if you put the ear very close to the driver.
but the other one has this high-frequent interference noise which is fluctuating.
The FA252 has the same noise issue. I didn't check any thermals or anything, but I'll do that later. I posted vid and graphs of the noise above
The changelog has a remark "Prepared for porting to OS X", so they must be preparing for that already.