Hi
I be been using a DAC/preamp to successfully drive my Class-D power amp, which has a 10k input impedance.The DAC/pre has an output impedance around 200 ohms.
I also have a pair Dayton DSP-LF units that i'd like to insert to analyse and room correct the lov end of my speakers; which should improve bass sound, since my tower speakers are placed out into the room for best stereo image.
However, I discovered the DSP-LF specs say its output is 1v and 10k ohms output impedance.
.
Using a 6ft shielded interconnect between the DSP and my power amp, if source and load are the same impedance, how would that affect the audio signal, and would there be a negative impact on the sound?
Alternatively, I could run the 6ft cable to the DSP, which could sit right at the amp...
Thanks
I be been using a DAC/preamp to successfully drive my Class-D power amp, which has a 10k input impedance.The DAC/pre has an output impedance around 200 ohms.
I also have a pair Dayton DSP-LF units that i'd like to insert to analyse and room correct the lov end of my speakers; which should improve bass sound, since my tower speakers are placed out into the room for best stereo image.
However, I discovered the DSP-LF specs say its output is 1v and 10k ohms output impedance.
.
Using a 6ft shielded interconnect between the DSP and my power amp, if source and load are the same impedance, how would that affect the audio signal, and would there be a negative impact on the sound?
Alternatively, I could run the 6ft cable to the DSP, which could sit right at the amp...
Thanks
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For driving cables, always use the lower source impedance possible and the higher at thr load end. Any source impedance will form with cable capacitance a low pass filter. The highs will be attenuated mose severely the higher the output impedance of the source, the greater the cable long and the cable capacitance. For normal situations, simply ignore it effect.
Okay, so if I keep the DSP-LF(1Vout/Z=10Kout) within a foot of the amplifier input(10Kin), do
I lose anything (other than maybe a little HF)?
What if power amp input impedance was 5k?
How does 10k:10k(or 10k:5k) impedance matching affect the audio signal with closely connected components? (I tried using Ohms Law, but that assumes a simple voltage divider)
Thanks.
I lose anything (other than maybe a little HF)?
What if power amp input impedance was 5k?
How does 10k:10k(or 10k:5k) impedance matching affect the audio signal with closely connected components? (I tried using Ohms Law, but that assumes a simple voltage divider)
Thanks.
RCA plug coax cable has about 100 pf per foot. Impedance of 6' cable 600 pf at 20 khz is 1/(2*pi*f*C) or 1/(12E4*6E-10)=1/72e-6) =13900 ohms. So using DAC to drive power amp you have 13.9k parallel the 10 k input, or 10k impedance driving 5.5 kohm impedance. It will be slightly more because the capacitance impedance & the resistance impedance are 90 degrees out of phase. Magnitude Zsum of Zr & Zc is the square root of the sum of the squares.
There will be some loss at 20 khz. Most men can't hear that anyway. Use a 3' RCA cable DAC to amp if you can hear that high. 1 foot cable would be better but they don't sell those.
There will be some loss at 20 khz. Most men can't hear that anyway. Use a 3' RCA cable DAC to amp if you can hear that high. 1 foot cable would be better but they don't sell those.
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Thanks.
I will consequently be biamplifying my system, with the DSP-LF feeding only the bass amp below 500hz, any hf roll-off should be outside the passband.
I've calculated (using Ohms Law) that the signal level to the bass amp will be down several dB, due to the impedance mismatch. I can then compensate at the analog high pass filter, which has a level pot.
Any other concerns of which I should be aware?
Thanks again.
I will consequently be biamplifying my system, with the DSP-LF feeding only the bass amp below 500hz, any hf roll-off should be outside the passband.
I've calculated (using Ohms Law) that the signal level to the bass amp will be down several dB, due to the impedance mismatch. I can then compensate at the analog high pass filter, which has a level pot.
Any other concerns of which I should be aware?
Thanks again.
I agree with speedskater. I looked it up on dayton's site and they do not specify it. I did find a review that did, and I am guessing it was a typo. I just cannot imagine the output is anything but an op-amp and that is not 10k. More like 100ohms.
The web-dweeb didn't bother to think. This means it is happy to drive a 10k load. As others are saying, the cheapest chips they could have used will drive much lower impedances to higher levels, but they don't promise that.
It is surely a 10 ohm chip and a 100-470 resistor. The chip's THD stays low down to 2k (TL072) or 600 (NE5532).