The theory is when everything is fine and not working. The practice is when everything works, but everyone doesn’t know why? :) I practice more. When I set my RMA audio interface to Sample Rate 48 kHz I have about 114 dB SINAD. Sample Rate at 192 kHz remains at about 110 dB SINAD.
I set the source level to + 6dB. At a source level of 0 dB, SINAD is about 94 dB (My post 200). The measurement was at highs signal levels - the measurement conditions were excellent. Maybe 90 dB is the minimum manufacturer specification to the sampling frequency 384 kHz. At a sampling frequency...
I checked the PCB. No H / Phone parts installed. In practice, I measured the output of the Poweramp through 470 Ohm resistor.
The artificial load was a resistor 33 Ohm /5W. In H / Phone mode disconnects the relays of speaker A and speaker B. There are no separate relays for H / Phone...
PCM1690 for Main Zone and PCM5100A NETWORK DAC for Z2. When I have a HEOS Main zone and set Zone 2 Source to HEOS is the same.
That's how it works. PCM1690 for Main Zone (SINAD 101dB) and PCM5100A NETWORK DAC for Z2 (SINAD is not measured by HEOS).
I marked 1,2,3 points on the ANALOGUE SOUND BLOCK chart. I shorten those points and check the signal path.
At CD input (coaxial), zone 2 Source: source, no signal sent to PCM1690. The signal passes through the PCM5100A DOWNMIX DAC (Point 3). Signal drop shorten only to point 3. Sorry I didn't...
Yes, post 200 Calibration mode. I connect RMA FIFEFACE Audio Interface Output to Audio Interface input. Testing generator is Audio interface output. Software: SpectraPlus_SC. Testing equipment SINAD is about 108 dB. All OK!
You read the measurement incorrectly. I measured only left canal output...
Modifications made, defects removed, housing closed.
An interesting measurement to finish.
Input - CD Coaxial. Zone 2 - ON. Zone 2 Source - Source.
At the top of the PRE OUT Main Zone.
At the bottom PRE OUT Zone 2.
DRA-800H modification done. PHONO input is replaced by "PRE OUT MAIN DAC". The signal is output directly from the PCM1690 op amp.
Checked Operating Inputs:
CD Coaxial SINAD about 100-101 dB
CD Analog SINAD about 91-92 dB (Theoretically without signal)
FM Signal of good quality (Theoretically...
There is no way to measure the HEOS signal quality. It only goes through the PCM5110A to the Z2. I'm thinking of PCM1690 output instead of PHONO input (I don't need it). The PHONO PCB can be easily removed, only a screwdriver is required.