Filter Button


#1

I recently changed preamps and I noticed my sound is much louder than previously with my older preamp. Should I be worried about the output from the ds being too much for it when its set to louder filter setting? I guess Im asking is the filter jut for volume or does it do something else and which setting gives the best sound or which is the preferred setting for a Preamp? I would imagine if you are using the ds directly to amps it help to go higher but I’m just not wanting to damage anything and get the best experience


#2

The “filter” button controls the 20dB attenuator. The attenuator only changes output levels by adding a shunt resistor to ground. The “high” level is still just a little less than most CD players so it’s fine with any normal preamp. If however (either with a preamp or plugged directly into an amp) you find that you always listen with the DS’s volume at 66 or less you should consider using the 20dB attenuator to give more volume range and to push the analog noise floor down by 20dB.


#3

Ted, i’m curious if you would have explanation for this curiosity:

In my setup (DS connected via balanced to EC AW400 solid-state mono blocks), the sound with -20dB shunt activated, the sound is less dynamic, softer and i have quite noticeable roll-off on the highs.

Can be this result of impedance/capacitance mismatch between the DS and my amps? Or anything else on your mind, why I would notice audible difference in sound characteristics between between attenuation on/off?

I was trying to match the levels on the DS to be almost the same when comparing the sound (i know not really scientific, but the difference is really obvious)

Amp parameters:

Input Impedance (Fixed) 330 kohm
Output Impedance (20 Hz-20kHz) < 0,01 Ohm
Frequency response (DC - 65 kHz) - 3 dB
Input level for rated output 1 V RMS
Max. peak current > 150 A
THD(measured at 1 kHzhalf power,8W) < 0,006 %
THD (measured at 1 kHz -1 dB, 8 W) < 0,007 %
Noise (measured with both inputs shorted) 400 Hz - 30 kHz : 130 µV DC - 30 kHz : 200 µV

Thank you! :)


#4

If you have high capacitance interconnects (or very long ones) they interact with the DS to roll off the top end if the attenuator is engaged (and counter intuitively) raise the top end with the attenuator not engaged. The amp’s input impedance doesn’t affect the rolloff nearly as much.


#5

Actually i’m using 1meter long XLO balanced cables, i’m not sure about their specific capacitance, but considering XLO is known for keeping capacitance/inductance and resistance low and also that it is only 1 meter cable I would believe the cable effect should be nearly negligible.

Could the sound change be somehow caused by noisy ground I am probably having in my flat? I have red somewhere here on the forums the shunt is connected to the ground when enabled (sorry for my ignorance in case i’m totally off :-) )

OR is there possibility that something could be wrong with my DS? I was upgrading the DS from the PWD with the PSA kit and noticed during the installation one surface-mount diode on the power board was not “seated properly” (apparently the board was hit against something hard in the factory/transport), but i have put it on right place and measured it’s functionality (it’s (in)-conductivity in both ways) and all seemed fine.

In general the DS has no issues whatsoever, i’m just listening without the shunt enabled as the sound is nicer, so not a great deal, i’m just trying to understand the beast bit more :-)


#6

If you like the sound better without using the 20dB attenuator, then, by all means don’t use it. The attenuator shunts both sides to the signal ground so it shouldn’t be affected by a noisy ground (at least not in the way you describe.)

I doubt that a diode in the power supply will cause the difference in sound when the 20dB attenuator is switched in or out.