Saw the same thing using Arta. Installing drivers for the E-MU 0404. Lets hope for better. I want to get a good set of measurements on the RIAA
The resolution is good. The Riaa will hover higher anyway. Any residual tip stuff we can count out now we saw the raw loop. No worries. But its a nuisance you can be better off cleaning if possible with the EMU.
Technically it is tomorrow I guess. Found the issue with the sound card, it was the driver. Took me many hours of frustration to find it. Back to M-Audio card as it has a lower noise level in this set-up.
Taken at 48000, 65536FFT Blackman. 0dB = 1Vrms
Taken at 48000, 65536FFT Blackman. 0dB = 1Vrms
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in your previous plots the 60Hz and the +-180Hz sidebands on the 1kHz were almost certainly mains and intermodulation with the third harmonic.
Your latest seems to have lost that mains interference.
Your latest seems to have lost that mains interference.
I agree as it makes perfect sense, but the only real difference between the good and bad was the software.dll used for the signal generation. I was able to repeat the same results and symptoms this morning.
Why is the third harminic so dominant?
I ask this as I have the RIAA hooked up right now. I don't see sidebands to the signal but I do see 60,120,180..... with the odd harminics spraying up into the higher freqs.
Why is the third harminic so dominant?
I ask this as I have the RIAA hooked up right now. I don't see sidebands to the signal but I do see 60,120,180..... with the odd harminics spraying up into the higher freqs.
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I don't know why the odd harmonics become so dominant. But they are the source of the buzz we hear when the PSU to Amp connection is not quite right.
How much of the issue could be related to incoming power quality? Just put my probe on the AC line-in and it looks like a triangle wave with the tops and bottom cut off tp fit it into 120V.
When I look at the harmonic spectrum closer it kind of looked like a triangle spectrum.
When I look at the harmonic spectrum closer it kind of looked like a triangle spectrum.
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You did not have such a harmonic noise with so high a fundamental before in any of your measurements. Something weird is going on. If you check your DC rails with the scope are they still a flat line? If your mains are a triangle indeed the field around the Tx must be terrible on the other hand.
I am trying to find a couple of batteries to take a picture from the scope. With kids and a Wii that is almost impossible. I could hear a wierd hum this morning, very faint but there.
Force Out is dead quite on the shunt per the scope.
I may try pulling the tranny out and moving it across the room.
Force Out is dead quite on the shunt per the scope.
I may try pulling the tranny out and moving it across the room.
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Is that IEC AC filter fishy? Could have had a blow? ...So bad a mains? Same if probing off the wall?
Hi,
is post4530 direct off the mains supply?
Note the odd harmonics are consistently higher than the even harmonics.
The tops chopped off is standard with our mains. Many consumers only draw current from the mains when the waveform is near maximum voltage.
Transformers feeding capacitor input filter.
SMPS that use a capacitor direct to rectified mains voltage do the same.
Changing the shape of the mains waveform from true sinusoidal to a flattened waveform can be recreated by introducing harmonics to extremely high frequency in the correct proportion and in the correct phase.
It's these harmonics in the mains supply that are the cause of many of our PSU problems.
is post4530 direct off the mains supply?
Note the odd harmonics are consistently higher than the even harmonics.
The tops chopped off is standard with our mains. Many consumers only draw current from the mains when the waveform is near maximum voltage.
Transformers feeding capacitor input filter.
SMPS that use a capacitor direct to rectified mains voltage do the same.
Changing the shape of the mains waveform from true sinusoidal to a flattened waveform can be recreated by introducing harmonics to extremely high frequency in the correct proportion and in the correct phase.
It's these harmonics in the mains supply that are the cause of many of our PSU problems.
Power line before the IEC looks the same.
Little different subject, but following through on a promise. Here is the turntable in action with the DL103R, Magnapan Unitrac I arm.
Better get the stuff of the camera before these are stolen as well!!!!
Little different subject, but following through on a promise. Here is the turntable in action with the DL103R, Magnapan Unitrac I arm.
Better get the stuff of the camera before these are stolen as well!!!!
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Its like the head shell has been designed to look OK only with that cart. Weird arm that Magnepan. The phono box looks good from side too. Reminds me of an early Musical fidelity Dr. Thomas from that angle.
