wgb113
Active Member
Making an active speaker switch to a less-integrated model and will need a preamp as a result. With a mix of consumer/pro gear I'm wondering if someone could explain in layman's terms how to use the specs to guide me in determining the proper gain structure. I'm looking for the best way to have the two sources be as close as possible to each other so that large volume adjustments aren't needed along with minimizing overall system noise while avoiding clipping. Most of the articles I've read are either very product-specific or in the professional realm where a preamp isn't in play. Output and input levels are as follows:
Phono Preamp Output Levels:
Nominal: 2.0V RMS (+6dBV)
Maximum: 6.3V RMS (+16dBV)
Impedance: 200 Ohm
SNR: 107 dB
DAC Output Levels:
Selectable: 0/+1/+7/+13/+19dBu
SNR: +1 dBu: 117dB RMS/120dBA, +7/+13/+19 dBu: 120dB RMS/123dBA
THD+N @ 0 dBFS: -116dB, 0.00016%
Impedance: 200 Ohm
Preamp Levels:
Passive OR:
@ 0dB:
THD: <0.001% at 2V RMS
IMD: <0.001%, CCIR
SNR: >115dB, A-weighted, referenced to 2V RMS
Impedance: 600 Ohm
@+12dB:
THD: <0.002% at 2V RMS
IMD: <0.002%, CCIR
SNR: >110dB, A-weighted, referenced to 2V RMS
Impedance: 600Ohm
Active Speakers:
Sensitivity: 85dB @ 1M free-field
+6dB Setting = 50mV (0dBu/0.775V max)
0dB Setting = 100mV (+6dBu/1.5V max)
-6dB Setting = 200mV (+12dBu/3.1V max)
The phono preamp output levels seem like they're tied to cartridge loading so that's somewhat fixed in that range. The DAC offers some adjustability so I'm guessing that's where I could best get a match between the two but I've also read that you should try to maximize the output of each device (without clipping) so that could cause a mis-match.
Then with 3 selectable options each on the preamp and speakers the speaker manufacturer recommends the -6dB setting for most consumer gear outputs which the preamp is. Is it simply a matter of experimenting with each or can the numbers be a guide?
Bill
Phono Preamp Output Levels:
Nominal: 2.0V RMS (+6dBV)
Maximum: 6.3V RMS (+16dBV)
Impedance: 200 Ohm
SNR: 107 dB
DAC Output Levels:
Selectable: 0/+1/+7/+13/+19dBu
SNR: +1 dBu: 117dB RMS/120dBA, +7/+13/+19 dBu: 120dB RMS/123dBA
THD+N @ 0 dBFS: -116dB, 0.00016%
Impedance: 200 Ohm
Preamp Levels:
Passive OR:
@ 0dB:
THD: <0.001% at 2V RMS
IMD: <0.001%, CCIR
SNR: >115dB, A-weighted, referenced to 2V RMS
Impedance: 600 Ohm
@+12dB:
THD: <0.002% at 2V RMS
IMD: <0.002%, CCIR
SNR: >110dB, A-weighted, referenced to 2V RMS
Impedance: 600Ohm
Active Speakers:
Sensitivity: 85dB @ 1M free-field
+6dB Setting = 50mV (0dBu/0.775V max)
0dB Setting = 100mV (+6dBu/1.5V max)
-6dB Setting = 200mV (+12dBu/3.1V max)
The phono preamp output levels seem like they're tied to cartridge loading so that's somewhat fixed in that range. The DAC offers some adjustability so I'm guessing that's where I could best get a match between the two but I've also read that you should try to maximize the output of each device (without clipping) so that could cause a mis-match.
Then with 3 selectable options each on the preamp and speakers the speaker manufacturer recommends the -6dB setting for most consumer gear outputs which the preamp is. Is it simply a matter of experimenting with each or can the numbers be a guide?
Bill