Just to be clear ... the Topping D10 can be powered through a wall transformer or directly from a PC usb port. You tried both ways and no change.
Yes the D10 is USB powered and no change.
I have been experimenting all day and it seems like the crossovers are introducing the hum. Now, I doubt that they are faulty I am guessing the fact that they are added in the chain must have something to do with it. Both are adding the same amount of hum.
The good news is that when I connect the DAC>AMP>Woofer the hum is significantly reduced, to be honest its gone there is still a buzz but you got to put your ear right up to the woofer. To make sure this noise was not harmful I executed a test with Audiolense to see if the signal to noise ratio was normal and I could get a successful measurement.
In my old set up both crossovers don't produce any hum or hiss or buzz for that matter. But in a bi amp setup it does so not sure what is happening.
I have been experimenting all day and it seems like the crossovers are introducing the hum. Now, I doubt that they are faulty I am guessing the fact that they are added in the chain must have something to do with it. Both are adding the same amount of hum.
The good news is that when I connect the DAC>AMP>Woofer the hum is significantly reduced, to be honest its gone there is still a buzz but you got to put your ear right up to the woofer. To make sure this noise was not harmful I executed a test with Audiolense to see if the signal to noise ratio was normal and I could get a successful measurement.
In my old set up both crossovers don't produce any hum or hiss or buzz for that matter. But in a bi amp setup it does so not sure what is happening.
What are you using for interconnects?
My system uses a laptop with a Topping DAC as well. If I use a wall wort for power to the DAC it will hum/static, etc. Powered from the laptop it's dead silent.
RCA cables from the laptop to the DAC, DAC to signal booster also RCA (if I use another piece of equipment here in place of the signal booster, Yamaha YDP2006 digital EQ w/built in booster, it's RCA from the DAC to XLR plug end at the other side ... minus the GND shield connection) From there it's balanced XLR to the crossover and then to the amps.
My system uses a laptop with a Topping DAC as well. If I use a wall wort for power to the DAC it will hum/static, etc. Powered from the laptop it's dead silent.
RCA cables from the laptop to the DAC, DAC to signal booster also RCA (if I use another piece of equipment here in place of the signal booster, Yamaha YDP2006 digital EQ w/built in booster, it's RCA from the DAC to XLR plug end at the other side ... minus the GND shield connection) From there it's balanced XLR to the crossover and then to the amps.
Last edited:
Well from the Marantz(DAC Preamp) to > Crossover> amplifier its all XLR cables.
With the D10 its RCA with adapter for input into the crossover then XLR the rest
The Hypex is dead quiet as an amp, as far as I know. And connecting it directly to the woofer with both the Marantz and D10 no hum.
With the D10 its RCA with adapter for input into the crossover then XLR the rest
The Hypex is dead quiet as an amp, as far as I know. And connecting it directly to the woofer with both the Marantz and D10 no hum.
Is your PC's sound card bad?
Also, your XLR cable .. roll your own or ? If you made 'em ... check the wiring.
Also, your XLR cable .. roll your own or ? If you made 'em ... check the wiring.
Last edited:
USB goes into the DAC bypasses the computer sound card, technically I don't have a soundcard. Its not the comp cause Ive had not problems prior to this set up. Even when my Marantz had some buzz it was easily fixed playing around with the wires, and outlets.
I'm pretty sure its something to do with the crossovers, but how to find a solution? That is problem at hand.
I'm pretty sure its something to do with the crossovers, but how to find a solution? That is problem at hand.
If you've isolated the problem to the XO's .. do they have a GND lift switch? Other than that, I've got nothin'. Hope you figure it out.
Next, try crossover>amp, without the DAC. Try also while shorting the input. What is the gain of the crossover?when I connect the DAC>AMP>Woofer the hum is significantly reduced
I'm not seeing the ground issue based on what I've read so far, unless something is broken or has been modified.
When I take the DAC out of the equation the noise is still there, makes no difference. Hence, why I suspect its the crossovers. Even with both DAC's the noise is the same. Even when switching the power points around with the amps and the DAC's no difference.
I apologize for my amateurish knowledge but i get most things its just the way its been put is hard to pick up immediately.
When you say try shorting the input, can you explain one more time? Is that what you mean short the inputs? Which inputs?
I am not fully understanding when you ask what the gain like? You mean what volume its on? When I play around with the volume on the crossovers there is a slight attenuation but the hum is still there. It doesn't disappear. I tried a measurement with Audiolense even with the volume on the crossover very low, but the signal to noise ratio was still horrible.
In saying that, I also tried a measurement sweep without the crossover just for the woofer and I got a a good dynamic range so the buzz is minimal that I am getting from the DAC>AMP>Woofer. At least I can go down this route in future if i can't figure out what is happening with the active crossover in the chain.
So if it's not a ground issue that's good news I reckon. Possibility the chances of getting to the bottom of it increases. I am presuming isolator will probably wont work.
It seems like the crossovers are the culprit but why its adding so much noise is a mystery, plus why both of them? And why in this particular setup and not others?
I apologize for my amateurish knowledge but i get most things its just the way its been put is hard to pick up immediately.
When you say try shorting the input, can you explain one more time? Is that what you mean short the inputs? Which inputs?
I am not fully understanding when you ask what the gain like? You mean what volume its on? When I play around with the volume on the crossovers there is a slight attenuation but the hum is still there. It doesn't disappear. I tried a measurement with Audiolense even with the volume on the crossover very low, but the signal to noise ratio was still horrible.
In saying that, I also tried a measurement sweep without the crossover just for the woofer and I got a a good dynamic range so the buzz is minimal that I am getting from the DAC>AMP>Woofer. At least I can go down this route in future if i can't figure out what is happening with the active crossover in the chain.
So if it's not a ground issue that's good news I reckon. Possibility the chances of getting to the bottom of it increases. I am presuming isolator will probably wont work.
It seems like the crossovers are the culprit but why its adding so much noise is a mystery, plus why both of them? And why in this particular setup and not others?
Tell me if the crossover isn't single-ended input and output.
Take you multimeter and do a few things, post your results if you think they are interesting. Measure resistance from the input ground to the output ground. Turn the unit on and measure Vdc and Vac at the input terminals (one probe on shield and one into the RCA socket, make sure it makes contact in there). Measure Vdc at the output.
Use your oscilloscope to show the output waveform with volume turned up and down.
Take you multimeter and do a few things, post your results if you think they are interesting. Measure resistance from the input ground to the output ground. Turn the unit on and measure Vdc and Vac at the input terminals (one probe on shield and one into the RCA socket, make sure it makes contact in there). Measure Vdc at the output.
Use your oscilloscope to show the output waveform with volume turned up and down.
I thought ill continue on this post as everybody was really helpful and I was thinking I would post my progress here as well. Attempting to find the hum didn't produce any results so I just forgot about it and moved forward with my goal of digital crossovers.
But, connecting the UDIO-8 to my amp to the tweeters causes some hiss as well. I managed to get a good dynamic range measurement so its not that bad but I just thought ill ask if any one has any ideas? Is this normal? I tried every combination and the woofer does not have any hiss or hum but the compression driver does. The amp is hypex and a music fidelity DAC so both are quiet.
My other question is after measuring my B&C DE250 dropped after about 12000khz is that also normal? I thought it should get to about 16000khz according to the spec sheet?
So far I have only tried crossing over at 1600hz and it sounds great. Something is missing and it could be the voice frequencies being played from the woofer and not all from the compression driver but all in all more than satisfactory. I will add some tuning from parametric EQ in Jriver was needed plus I still can add two superb subs as well as trying lower crossover points.
But, connecting the UDIO-8 to my amp to the tweeters causes some hiss as well. I managed to get a good dynamic range measurement so its not that bad but I just thought ill ask if any one has any ideas? Is this normal? I tried every combination and the woofer does not have any hiss or hum but the compression driver does. The amp is hypex and a music fidelity DAC so both are quiet.
My other question is after measuring my B&C DE250 dropped after about 12000khz is that also normal? I thought it should get to about 16000khz according to the spec sheet?
So far I have only tried crossing over at 1600hz and it sounds great. Something is missing and it could be the voice frequencies being played from the woofer and not all from the compression driver but all in all more than satisfactory. I will add some tuning from parametric EQ in Jriver was needed plus I still can add two superb subs as well as trying lower crossover points.
- Home
- Loudspeakers
- Multi-Way
- Fusion 15's vs Econowave Deltalite vs another option