I think I'm having issues with a low-line level from my source in a home audio system. My output volume is low and I have to turn the volume knob/amp up all the way to get somewhat decent output out of my sub. I am also experiencing distortion with each bass hit that gets worse as I turn the volume up.
Does the distortion I'm experiencing line up with the effects of a line level that is too low or might I have another issue going on in tandem?
Thanks!
Does the distortion I'm experiencing line up with the effects of a line level that is too low or might I have another issue going on in tandem?
Thanks!
The source is a PopPulse Super Pro DAC707-USB. This is in relation to my earlier subwoofer issue post.
I suppose what I would like to hear someone say is "Yes, distortion like that can definitely be caused by low line levels. A line-level booster will fix the problem," or something like that. Or if the answer is "No, distortion like that isn't common with low-line levels, you have a bigger issue you need to work through," then I'll know I need to get to work diagnosing the problem.
The best I can say is:
An unacceptably low input level would result in a poor signal to noise ratio. The inadequate output would be accompanied by an excess of 'hiss and hum'.
It is signal to noise ratio that would be improved by having more gain in the early links of your amplification chain.
Distortion would only result from an unacceptably high input level.
An unacceptably low input level would result in a poor signal to noise ratio. The inadequate output would be accompanied by an excess of 'hiss and hum'.
It is signal to noise ratio that would be improved by having more gain in the early links of your amplification chain.
Distortion would only result from an unacceptably high input level.
Is there any software for this DAC installed on the system? If so, is there any software controlled volume that can be adjusted?
MKGus
Does Your sub have line input, or is it speaker input ? If it is speaker input, You have to bypass or lower the resistors in the sub in order to get a decent level. Does it work connected to an ordinary RCA amp input ?
Does Your sub have line input, or is it speaker input ? If it is speaker input, You have to bypass or lower the resistors in the sub in order to get a decent level. Does it work connected to an ordinary RCA amp input ?
I believe I understand what you are asking but it may not be applicable in my situation. The sub is driven by a Crown XLS pro amp. The connection to it is an RCA cable. I have purchased a line-level booster to boost the signal right after the DAC. I'll post here again once I test it. Fingers crossed!
Distortion on loud low frequency bass is often a sign of tired rail capacitors in the amp. XLS is an old product, is your amp over 15 years old? Or any other tired electrolytic capacitor in the signal chain.
You could test your line level too low theory by plugging the headphone output of an FM radio or CD player into the input of the amp . 1/8" stereo phone plug to dual RCA plug adapter, about $4. headphone outputs typically will go up to 6 vac or so. That should get enough drive voltage for your amp to be really loud with low setting of the volume knob.
BTW I test for rail capacitors in amps by checking the AC voltage coming out at max volume on a speaker or 4 or 8 ohm resistor. W=(V^2)/R If the amp watts are low compared to spec at max volume, your rail capacitors have dried up. Use an analog Voltmeter, not a DVM, those lie a lot on music. 5000 ohm/volt (cheap) meter is fine at speaker current levels.
When an aged amp acts up, I change ALL the electrolytic capacitors, not just the rail ones. Historic rubber sealant is really dirt after a decade or so.
You could test your line level too low theory by plugging the headphone output of an FM radio or CD player into the input of the amp . 1/8" stereo phone plug to dual RCA plug adapter, about $4. headphone outputs typically will go up to 6 vac or so. That should get enough drive voltage for your amp to be really loud with low setting of the volume knob.
BTW I test for rail capacitors in amps by checking the AC voltage coming out at max volume on a speaker or 4 or 8 ohm resistor. W=(V^2)/R If the amp watts are low compared to spec at max volume, your rail capacitors have dried up. Use an analog Voltmeter, not a DVM, those lie a lot on music. 5000 ohm/volt (cheap) meter is fine at speaker current levels.
When an aged amp acts up, I change ALL the electrolytic capacitors, not just the rail ones. Historic rubber sealant is really dirt after a decade or so.
Last edited:
A follow up: I added a line-level booster between my DAC & volume control and my Crown amp that powers my sub: iBoost 800 Stereo Line Level Audio Amplifier. This seems to have taken care of my problem with the sub/amp having low output and the sub producing distorted sound. I keep the line level booster on high and control the sub volume with the Crown amp. Thank you to everyone for your help!!
- Status
- Not open for further replies.