XDA-1 gainproblem solution?

[honk]

Hi,

no doubt, I like the XDA1, but the gainlevels are a joke.

In the lowest step (0.5) my system is to loud for some situations. (USB, XDA, XPA1, 90dB speakers, XLR)

Level 1 / 80 is fair for most situations, and level 3-5 is on the loud side.

Sorry, but this gain regulation is useless!
It should be spreaded 10 times, so that 1 becomes 10, and 5 fifty.

We need a workaround here (at least).

KR

[Erwin.BE]

With my Weiss DAC2 and two XPA-1 combo this problem also exists. The DAC2 uses digital volume control via two front buttons and has four pre-set analogue output voltages. Even the lowest pre-set needs to much of digital attenuation to be ideal.

Digital volume control is inferior because it reduces the world lenght. It's like you use a 1080i picture, zoom in to a part of it (576i) and blow this part up to fit a 1080p teevee. It's just not the same. So 16 bits is reduced to 12 bits if you use digital volume control. The high gain of the XPA's is a problem. I tried XLR passive attenuator (-10dB) from Rothwell, but it took away some of the edge of the sound. Maybe some frequencies were more muted than others.

To bad the XDA-1 actually adds to this problem instead of improving the situation! To have best SQ, the digital volume control should be near the maximum.

[RPA-1 man]

From everything I've read so far about the gain situation of the XDA, it seems it may have been designed primarily to be used between the source and a preamplifier.

The only other solutions I see if you are not using a preamp are to use it with an amplifier that has adjustable gain or add passive attenuators in the signal path.

I have a Pioneer cdp with digital level control and I can't hook it up directly to my amp because it does not lower the volume enough for night time listening.

Is this a common problem with digital volume controls? Maybe Lonnie can fill us in.

[Chuck Elliot]

Dec 4, 2010 7:34:00 GMT -5 Erwin.BE said:

...I tried XLR passive attenuator (-10dB) from Rothwell, but it took away some of the edge of the sound. Maybe some frequencies were more muted than others....

How does the use of a properly designed in-line attenuator hurt the signal in any way? We're only talking resistors here. As long as it doesn't muck with the source or destination impedance, it should do nothing but attenuate the signal just as an analog volume control would.

I'm not being argumentative here, just trying to understand?

[rockguitar]

Dec 4, 2010 7:34:00 GMT -5 Erwin.BE said:

With my Weiss DAC2 and two XPA-1 combo this problem also exists. The DAC2 uses digital volume control via two front buttons and has four pre-set analogue output voltages. Even the lowest pre-set needs to much of digital attenuation to be ideal.

Digital volume control is inferior because it reduces the world lenght. It's like you use a 1080i picture, zoom in to a part of it (576i) and blow this part up to fit a 1080p teevee. It's just not the same. So 16 bits is reduced to 12 bits if you use digital volume control. The high gain of the XPA's is a problem. I tried XLR passive attenuator (-10dB) from Rothwell, but it took away some of the edge of the sound. Maybe some frequencies were more muted than others.

To bad the XDA-1 actually adds to this problem instead of improving the situation! To have best SQ, the digital volume control should be near the maximum.

I think the best information out there right now, is that the volume control built into the AD1955 used in the XDA is an analog volume control, not digital. Only thing digital about it is using a digital display.

[rockguitar]

Dec 4, 2010 4:38:39 GMT -5 honk said:

Hi,

no doubt, I like the XDA1, but the gainlevels are a joke.

In the lowest step (0.5) my system is to loud for some situations. (USB, XDA, XPA1, 90dB speakers, XLR)

Level 1 / 80 is fair for most situations, and level 3-5 is on the loud side.

Sorry, but this gain regulation is useless!
It should be spreaded 10 times, so that 1 becomes 10, and 5 fifty.

We need a workaround here (at least).

KR

Like I posted in detail in this thread, emotivalounge.proboards.com/index.cgi?action=display&board=preampdac&thread=15010&page=1#233478

there is nothing wrong with the gain of the XDA, the problem at low volumes is that the volume control is a linear volume control instead of logarithmic so it does not allow for fine control at low volumes.

Solutions are to 1) use a preamp or 2) use a passive preamp or volume control, e.g. stepped attenuators or an ALPS volume control or 3) simply use two resistors to step down the output voltage, this is done commercially here www.tweakaudio.com/Fixed%20Volume%20Ultimate%20Attenuators.html

[cawgijoe]

I won't be able to set my XDA-1 up till Christmas day. This should probably be put in the Stupid Question thread.....I'll be using it with a Pioneer Elite VSX-01 receiver......ERC-1......and Squeezebox Duet........what do I set the volume on....XDA-1.....and will I have any gain/volume issues?

I'm thinking no since I'll be using the Pioneer for volume........but can someone clarify?

Thanks!

[ocean2059]

If you're using your receiver to control the volume, you could set the gain control to max, 80.

[rockguitar]

Dec 4, 2010 9:32:53 GMT -5 rockguitar said:

Dec 4, 2010 4:38:39 GMT -5 honk said:

Hi,

no doubt, I like the XDA1, but the gainlevels are a joke.

In the lowest step (0.5) my system is to loud for some situations. (USB, XDA, XPA1, 90dB speakers, XLR)

Level 1 / 80 is fair for most situations, and level 3-5 is on the loud side.

Sorry, but this gain regulation is useless!
It should be spreaded 10 times, so that 1 becomes 10, and 5 fifty.

We need a workaround here (at least).

KR

Like I posted in detail in this thread, emotivalounge.proboards.com/index.cgi?action=display&board=preampdac&thread=15010&page=1#233478

there is nothing wrong with the gain of the XDA, the problem at low volumes is that the volume control is a linear volume control instead of logarithmic so it does not allow for fine control at low volumes.

Solutions are to 1) use a preamp or 2) use a passive preamp or volume control, e.g. stepped attenuators or an ALPS volume control or 3) simply use two resistors to step down the output voltage, this is done commercially here www.tweakaudio.com/Fixed%20Volume%20Ultimate%20Attenuators.html

Solution 3) can be done by using in-line rca or xlr attenuators. Here are some inexpensive options.

www.parts-express.com/wizards/searchResults.cfm?srchExt=CAT&srchCat=725&CFID=14079117&CFTOKEN=35894395
www.parts-express.com/wizards/searchResults.cfm?FTR=xlr+attenuator&search_type=main&WebPage_ID=3&searchFilter=xlr+attenuator&x=0&y=0

[DYohn]

Why not just run the XDA-1 through your preamp? If the gain structure is too ragged to use the DAC as your preamp, then set it to one output level that works well with your existing preamp and use it as an, err, DAC. Seems simple to me.

[Tonys]

I've got mine running into my VTL IT-85 (integrated el34 amp) and the gain is a bit over the top when the XDA is set at 80. There's no real improvement until < 45 for low level listening.

Sounds great btw. Can't wait to run it in.

[srb]

I am using the XDA-1 with my AV preamp, and while a maximum volume setting of 80 is OK, I have set it to 73 just to exactly match the level I get when I use the internal DAC of the preamp, which lets me more accurately compare the DACs as well as match levels to my multi-channel and analog sources.

As has been previously mentioned (and both verified by Emotiva and Analog Devices), the on-chip volume control implementation is an analog resistor ladder, albeit digitally controlled, and doesn't use up bits to attenuate.

I am curious if there is will be any possible method or access for the user to update firmware, not only to modify the volume control taper for those using the XDA-1 direct-to-amplifier, but in my case also for the front panel dimming function.

I was surprised (and dismayed) to find that it did not cycle through an all-lights-off position (to be momentarily displayed for a second or two when making an adjustment), like 3 of my other display-equipped components.

It's hard for me to imagine anyone wanting anything brighter than the current lowest dimming value, and to only go down from there. It's like my normally subdued rack has invited a carnival to town, but I guess that's a subject for a whole new topic!

Steve

[sharkman]

I was also concerned about the gain level of the XDA, and just received it today. With uncertain expectations, I connected my ERC via coax, then RCA's to my XPA-3. After testing it with a dozen cds of different recording levels/quality, including HDCD and XRCD, i can say I'm not concerned about the gain levels. With typical cds I have usable volume up to 22 or so on the XDA, which is 44 volume options. At this level I'm measuring 90-92DB peaks, so some could happily go higher.

On HDCD cds, it's around 16 or so on the volume level. But I haven't tried USB inputs. It seems like the gain of signals going into the XDA might vary greatly, thus making it more difficult to have a volume range that would be a perfect match for each.

At any rate the SQ is definitely better than with the ERC alone. Right across the frequency spectrum, everything is cleaner, more transparent and a little more defined. You can color me happy!

I am no longer completely happy. After more research and experimentation, I agree that the volume is not properly implemented.

[MukAudio]

Dec 4, 2010 10:30:50 GMT -5 DYohn said:

Why not just run the XDA-1 through your preamp? If the gain structure is too ragged to use the DAC as your preamp, then set it to one output level that works well with your existing preamp and use it as an, err, DAC. Seems simple to me.

The only bummer about that is Emotiva has said repeatedly that sound would be superior going direct from DAC to amp.

Mark.

[Tonys]

;D

For years I was a Wadia owner and even with variable gain and a volume controls it just wasn't practical. It offered the same digital preamp capabilities but very few owners used them that way.

My VTL has a processor bypass so I'll try it that way and report back in a few days.
Tony

[CrazyBlue]

Found this balanced analog volume control in another thread:

www.tcelectronic.com/levelpilot.asp

www.sweetwater.com/store/detail/LevelPilot/



Thread: emotivalounge.proboards.com/index.cgi?board=chat&action=display&thread=13182

$79.00 at Sweetwater. Looks like it would work to solve the linear volume problem. Connect the XDA-1 via balanced outs to the Level Pilot and connect it to your amp(s) (if your amp(s) have balanced inputs) and voila! Analog volume control. Only drawback is you lose the remote. And I think the supplied cables are pretty short.

Another member uses a Goldpoint passive preamp.

www.goldpt.com/index.html



They're four times the price though and it goes up from there.

[Erwin.BE]

Dec 4, 2010 9:30:04 GMT -5 rockguitar said:

Dec 4, 2010 7:34:00 GMT -5 Erwin.BE said:

With my Weiss DAC2 and two XPA-1 combo this problem also exists. The DAC2 uses digital volume control via two front buttons and has four pre-set analogue output voltages. Even the lowest pre-set needs to much of digital attenuation to be ideal.

Digital volume control is inferior because it reduces the world lenght. It's like you use a 1080i picture, zoom in to a part of it (576i) and blow this part up to fit a 1080p teevee. It's just not the same. So 16 bits is reduced to 12 bits if you use digital volume control. The high gain of the XPA's is a problem. I tried XLR passive attenuator (-10dB) from Rothwell, but it took away some of the edge of the sound. Maybe some frequencies were more muted than others.

To bad the XDA-1 actually adds to this problem instead of improving the situation! To have best SQ, the digital volume control should be near the maximum.

I think the best information out there right now, is that the volume control built into the AD1955 used in the XDA is an analog volume control, not digital. Only thing digital about it is using a digital display.

My bad, I missed that info then.

[Erwin.BE]

Dec 4, 2010 9:27:04 GMT -5 Chuck Elliot said:

Dec 4, 2010 7:34:00 GMT -5 Erwin.BE said:

...I tried XLR passive attenuator (-10dB) from Rothwell, but it took away some of the edge of the sound. Maybe some frequencies were more muted than others....

How does the use of a properly designed in-line attenuator hurt the signal in any way? We're only talking resistors here. As long as it doesn't muck with the source or destination impedance, it should do nothing but attenuate the signal just as an analog volume control would.

I'm not being argumentative here, just trying to understand?

Well, I don't have measurements to prove it and the difference is marginal, but I could swear the SQ is a tiny bit degraded with them. A bit less detail and clarity. And it should be the other way round, or else why bother?

I am still waiting for the 6moons review of the StereoKnight passive pre-amp, which uses magnets (and not resistors) to reduce the volume.
www.6moons.com/audioreviews/stereoknight/1.html

[rockguitar]

Dec 4, 2010 10:30:50 GMT -5 DYohn said:

Why not just run the XDA-1 through your preamp? If the gain structure is too ragged to use the DAC as your preamp, then set it to one output level that works well with your existing preamp and use it as an, err, DAC. Seems simple to me.

I think a lot depends on the quality of the preamp/receiver. For a pure stereo quality perspective, a preamp/receiver can do more to muck up the signal than resistors. If the DAC/amp interface is sufficient then a direct connection to the amp will allow the greatest detail and transparency. When I had a Benchmark Dac1, I connected the Cd-->DAC-->DACT attenuators (volume control) --> amp. I preferred the volume control of the DACT to the internal one of the DAC1. That was a very transparent and detailed setup.

[wizardofoz]

Dec 4, 2010 11:06:51 GMT -5 srb said:

I am using the XDA-1 with my AV preamp, and while a maximum volume setting of 80 is OK, I have set it to 73 just to exactly match the level I get when I use the internal DAC of the preamp, which lets me more accurately compare the DACs as well as match levels to my multi-channel and analog sources.

As has been previously mentioned (and both verified by Emotiva and Analog Devices), the on-chip volume control implementation is an analog resistor ladder, albeit digitally controlled, and doesn't use up bits to attenuate.

I am curious if there is will be any possible method or access for the user to update firmware, not only to modify the volume control taper for those using the XDA-1 direct-to-amplifier, but in my case also for the front panel dimming function.

I was surprised (and dismayed) to find that it did not cycle through an all-lights-off position (to be momentarily displayed for a second or two when making an adjustment), like 3 of my other display-equipped components.

It's hard for me to imagine anyone wanting anything brighter than the current lowest dimming value, and to only go down from there. It's like my normally subdued rack has invited a carnival to town, but I guess that's a subject for a whole new topic!

Steve

+1 on all of the above