DC-1

[KeithL]

Actually, the "fixed output" on the DC-1 uses the exact same signal path as the "variable output" - it literally just sets the gain to 0 dB and locks it so you can't change the setting.
Likewise, the signal passes through the exact same circuitry regardless of the gain setting (except for different passive resistors chosen by identical switches in the volume control).
So, if there are any differences at different levels - other than the level - they really should be minimal.

Mar 4, 2014 15:06:01 GMT -5 ads said:

Mar 4, 2014 10:47:34 GMT -5 KeithL said:

Honestly, I would be inclined to suspect that the preamp was boosting the upper midrange
just a tiny bit - which will produce an apparent increase in "brightness" AND "detail" - and removing it eliminated this effect. The reality is that any component will produce some change - which may or may not be audible. (People argue endlessly about "what amount of change is audible", but even a slight boost in treble, which may not be audible as a difference in frequency response, may still be audible as "more detail".) Passive components (like resistors) generally produce the least amount of difference; and even moderately good resistors are more transparent than all but the best active components. (And "additive math logic" applies; if adding a component produces a change, and removing it removes the change, then the component itself usually is changing something.)

When you connect an interconnect cable, or another component, to the output of a FULLY PASSIVE preamp - which is really just a set of resistors - you may also get changes because of how the resistance interacts with the capacitance of the interconnect cable itself - and because the source impedance will actually change significantly depending on the setting. However, this specific interaction will not happen with the DC-1 (the DC-1's resistor ladder volume network is followed by an active buffer stage, so the output of the DC-1 shouldn't be subject to load interactions - the DC-1 doesn't significantly change output impedance at different volume settings).

It’s possible that the Cambridge pre is adding something or that the DC-1 variable output is subtracting something. I mean this is a hypothetical way, as I have no objective evidence for either case.

I’m open to the possibility that the DC-1 variable output is more neutral or accurate, but my ears and brain were telling me that something was missing.

Is there any additional circuitry in the signal path using the variable output? Is there an additional gain stage vs. using the fixed output?  Does the volume control attenuate the output in variable mode and also fix the volume to 0 in fixed mode?  I’m trying to understand if there are any significant circuit differences that could explain fixed vs. variable sound differences.

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Mar 4, 2014 15:56:57 GMT -5 KeithL said:

Actually, the "fixed output" on the DC-1 uses the exact same signal path as the "variable output" - it literally just sets the gain to 0 dB and locks it so you can't change the setting.
Likewise, the signal passes through the exact same circuitry regardless of the gain setting (except for different passive resistors chosen by identical switches in the volume control).
So, if there are any differences at different levels - other than the level - they really should be minimal.

Thanks for confirming this.

I take this to mean:
1) That the DC-1 should perform identically connected to a preamp in fixed mode vs. connected directly to amp(s) in variable mode set to 0 dB.
2) That the DC-2 should have consistent performance across the volume range.

Is it more "difficult" for the DC-1 to drive an amp vs. preamp at the same dB level setting?  

[d1sturb3d]

Mar 4, 2014 11:16:11 GMT -5 KeithL said:

The most recent (Unified) drivers support WASAPI PUSH mode (but not WASAPI EVENT) - so you have to select "disable Event Style" under device config (in jRiver).
(It will be on the device properties page - which you will only see once you have selected our DAC and WASAPI mode.)
If you really want to try WASAPI EVENT mode, then you can use the older drivers (which, however, don't support Windows 8).
(I don't hear any difference in sound between them...)

WASAPI is intended to be a bit perfect mode - so, since changing levels or balance requires changing bits, Windows disables those controls in WASAPI mode.
(Although some players may allow you to make changes in the player - before Windows gets control of the audio stream.)

In principle, this should work equally in USB as well as other modes, but that will of course depend on the player program you're using.
Windows itself should disable all controls and "special effects" in WASAPI mode.

Mar 2, 2014 13:59:25 GMT -5 eclypse said:

It will wotk with waspi as long as u set something called " stop events" or whatever ita called in the options. Also theres an option in jriver to change the speaker levels and distances in the speaker configuration.

just got my DC-1 and downloaded the driver in the product page? is that the latest one? I cannot use WASAPI push on Foobar, only WASAPI event is working..just saying..

btw..I didn't realized that the DC-1 is that small..I'll paint the mini-x black so they will match together..they look cute together though lol

[klinemj]

Per a few posts ago in this thread from Keith:

The most recent (Unified) drivers support WASAPI PUSH mode (but not WASAPI EVENT) - so you have to select "disable Event Style" under device config (in jRiver).
(It will be on the device properties page - which you will only see once you have selected our DAC and WASAPI mode.)

Mark

[d1sturb3d]

Mar 4, 2014 15:53:11 GMT -5 KeithL said:

You can get them at the bottom of the XDA-2 product page:

Emotiva XDA-2 Drivers Archive 11/27/2012 (.rar)


(The XDA-2 and DC-1 use the same drivers.)

Mar 4, 2014 11:41:42 GMT -5 eclypse said:

Where does one get the older drivers so o can hear the difference?

I uninstalled the XDA-2 driver thinking the DC-1 will be different..could have saved me a couple of minutes in setting up.

[KeithL]

Your 1) and 2) are (or should be) entirely correct.

The input impedances of various power amps and preamps vary considerably, but both are in the same range (either could be anywhere from 5k or 10k to a few megohms), and the DC-1 should have no trouble whatsoever driving either.

Mar 4, 2014 19:30:59 GMT -5 ads said:

Mar 4, 2014 15:56:57 GMT -5 KeithL said:

Actually, the "fixed output" on the DC-1 uses the exact same signal path as the "variable output" - it literally just sets the gain to 0 dB and locks it so you can't change the setting.
Likewise, the signal passes through the exact same circuitry regardless of the gain setting (except for different passive resistors chosen by identical switches in the volume control).
So, if there are any differences at different levels - other than the level - they really should be minimal.

Thanks for confirming this.

I take this to mean:
1) That the DC-1 should perform identically connected to a preamp in fixed mode vs. connected directly to amp(s) in variable mode set to 0 dB.
2) That the DC-2 should have consistent performance across the volume range.

Is it more "difficult" for the DC-1 to drive an amp vs. preamp at the same dB level setting?  

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Related to this topic, I’ve heard some folks say that dynamics or “slam” are not as good with the DC-1 in variable mode without a dedicated preamp. I’ve read this same thing about other digital sources with variable outputs.

I’ve always wondered, how can that be? What is the electrical phenomenon that could explain that?

Take a DAC like the DC-1 in fixed mode connected to a preamp - all the dynamic range (voltage swing) in the signal has to be in the DAC's output. A separate preamp can’t create dynamic range that is not in the DAC’s output. In most cases, a separate preamp is attenuating the input signal.

Following on this, using the variable output of the DC-1 at levels less than 0 dB, I would not expect that dynamic range (voltage swing) would be compromised, since the full dynamic range is output at even higher levels in fixed mode. In other words, the DC-1 should not run out of gas in terms of voltage swing dynamics in variable mode at 0 dB or lower vs. fixed mode at 0 db.

Whether you are using a separate preamp to attenuate or the DC-1 to attenuate, would not the dynamic range have to be limited by the DAC’s output?

The only thing I can think of to refute this would be the possibility that the variable output’s dynamic range is reduced at levels lower than 0 dB, and that a separate preamp preserves the higher dynamic range of the higher fixed output voltage.

This post is meant to be food for thought, not any type of definitive statement.

[garbulky]

Mar 5, 2014 13:09:16 GMT -5 ads said:

Related to this topic, I’ve heard some folks say that dynamics or “slam” are not as good with the DC-1 in variable mode without a dedicated preamp. I’ve read this same thing about other digital sources with variable outputs.

I’ve always wondered, how can that be? What is the electrical phenomenon that could explain that?

Take a DAC like the DC-1 in fixed mode connected to a preamp - all the dynamic range (voltage swing) in the signal has to be in the DAC's output. A separate preamp can’t create dynamic range that is not in the DAC’s output. In most cases, a separate preamp is attenuating the input signal.

Following on this, using the variable output of the DC-1 at levels less than 0 dB, I would not expect that dynamic range (voltage swing) would be compromised, since the full dynamic range is output at even higher levels in fixed mode. In other words, the DC-1 should not run out of gas in terms of voltage swing dynamics in variable mode at 0 dB or lower vs. fixed mode at 0 db.

Whether you are using a separate preamp to attenuate or the DC-1 to attenuate, would not the dynamic range have to be limited by the DAC’s output?

The only thing I can think of to refute this would be the possibility that the variable output’s dynamic range is reduced at levels lower than 0 dB, and that a separate preamp preserves the higher dynamic range of the higher fixed output voltage.

This post is meant to be food for thought, not any type of definitive statement.

The pre-amps I believe adjust the output impedance. So hopefully it makes it lower. At least that's what I've read. For me I think whatever coloration/alteration goes on at lower volumes is increased vs the signal vs at high volumes from the DC-1. Just my personal opinions which probably doesn't stand up to scrutiny though...

[eclypse]

Mar 5, 2014 15:00:57 GMT -5 eclypse said:

Dec 28, 2013 18:42:41 GMT -5 mumstead said:

When I first got my DC-1 I was going crazy trying to get event mode to work. Eventually I discovered that Schiit uses the same USB chip as Emotiva in its DACs so I downloaded the Schiit drivers for USB from their web site. When you unpack the drivers the contents of the folders appear to be nearly identical to the Emotiva drivers except for an ini file. The Schiit drivers work perfectly with my DC-1 and they allow me to use event mode without any problem. I have been using these drivers since shortly after I received my DC-1 early in October and it has been working perfectly in event mode with Windows 8.1 and JRiver 19 ever since.

Thanks for the info on the drivers.. savws me last night when i removed the newest drivers for the dc-1. I first tried to install the old xda-2 drivers and no matter bow many times i ininstalled and reinstalled them i could not get.the dc- drivers to install in win7 pro 64. Installed the Schiit drivers and bamb worked just fine and am able to use the event style mode just fine.

[eclypse]

Ment to say the old xda-2 drivers..could not get those to install at all.

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Over the weekend, had a strange experience using the DC-1 in variable mode without my preamp in the chain.

I had a high level of noise/hum from speakers connected to the B speaker outputs of my amps, which feed a Niles speaker selector and 3 pairs of speakers in separate locations. I was using the patio speakers only. I individually tested the other speaker pairs connected to the speaker selector, and they all had the noise. The noise is bad enough that I can't use the system with this configuration (no preamp). The amps' A speaker outputs, which I use in the main audio/video room, did not have the noise.

The noise does not exist with my preamp in the chain, independent of which DAC I have used, including the DC-1 in fixed mode. In other words, the noise only exists when the DC-1 is connected directly to my amps with the B speaker outputs engaged.

So, somehow, the DC-1 connected directly to my amps is generating noise with the B speaker outputs, but not the A speaker outputs. I wonder if the DC-1 is somehow picking up noise from the long runs of speaker wire associated with the B speaker outputs, and that somehow my separate preamp is immune to this.

I have no good explanation for the noise using the DC-1 directly to my amps, using the B speaker outputs, but I wonder if the phenomenon could be related to the reduced detail I hear in the main audio/video room (A speaker outputs) without my preamp in the chain.

Strange...

As a side note, my amps' input impedance is 30K ohm.

[novisnick]

I'm thinking that it may be the Niles. Pull it out and test each separately, I think you will find your problem.
SITD

[garbulky]

Mar 11, 2014 20:23:42 GMT -5 ads said:

Over the weekend, had a strange experience using the DC-1 in variable mode without my preamp in the chain.

I had a high level of noise/hum from speakers connected to the B speaker outputs of my amps, which feed a Niles speaker selector and 3 pairs of speakers in separate locations. I was using the patio speakers only. I individually tested the other speaker pairs connected to the speaker selector, and they all had the noise. The noise is bad enough that I can't use the system with this configuration (no preamp). The amps' A speaker outputs, which I use in the main audio/video room, did not have the noise.

The noise does not exist with my preamp in the chain, independent of which DAC I have used, including the DC-1 in fixed mode. In other words, the noise only exists when the DC-1 is connected directly to my amps with the B speaker outputs engaged.

So, somehow, the DC-1 connected directly to my amps is generating noise with the B speaker outputs, but not the A speaker outputs. I wonder if the DC-1 is somehow picking up noise from the long runs of speaker wire associated with the B speaker outputs, and that somehow my separate preamp is immune to this.

I have no good explanation for the noise using the DC-1 directly to my amps, using the B speaker outputs, but I wonder if the phenomenon could be related to the reduced detail I hear in the main audio/video room (A speaker outputs) without my preamp in the chain.

Strange...

As a side note, my amps' input impedance is 30K ohm.

You're not the first person with that issue. Pull out the power cord. Wait 30 seconds and reinsert. See what happens. (Literally remove the power cord and reinstert)

[rod]

Is zero the right volume on DC 1 functioning as DAC?

[novisnick]

Mar 14, 2014 21:26:16 GMT -5 rod said:

Is zero the right volume on DC 1 functioning as DAC?

Yep

[rod]

Mar 14, 2014 21:30:11 GMT -5 novisnick said:

Mar 14, 2014 21:26:16 GMT -5 rod said:

Is zero the right volume on DC 1 functioning as DAC?

Yep

Thank you! I just got it. The DC1 and xda2 are both connected to xsp1 , transport ERC1....

[novisnick]

way cool rod! Fire them up,I will not comment at this point. Ill just sit and wait for your impressions

Nick

[rod]

Mar 14, 2014 22:21:43 GMT -5 novisnick said:

way cool rod! Fire them up,I will not comment at this point. Ill just sit and wait for your impressions

Nick

Well I guess you know exactly what I will say about my impression for these two machines. Hahaha. By the way, the right side of Dc1 is a little bit hot.. Is it supposed to be like that?

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Spent some time yesterday troubleshooting the noise issue with the B speaker outputs from my amps using the DC-1 without a separate preamp.

The vast majority of the noise must be coming from the run of 4 conductor speaker wire from the amps to the Niles speaker selector. I ran a temporary/test set of spliced together wires from the amps to the selector, and the vast majority of the noise disappeared.

Before I did this, I noticed that the right channel of the A speaker outputs had some noise relative to the left channel, but nowhere close to the amount of noise with the B speaker outputs. This was the case even with my current Cambridge preamp and a Parasound 2100 I got last week. I decided to change the interconnects from the preamp (tested the Cambridge, Parasound, and DC-1) to the amps, and the right channel noise was eliminated (went from MIT Terminator 2 to some AR interconnects).

Strangely, changing the interconnects improved the A speaker output right channel, but created the high level of noise with both channels of the B speaker outputs with all 3 preamp options. With the original interconnects, only the DC-1 as preamp resulted in noise in the B outputs.

So, ultimately, the combination of changing the preamp to amp interconnects and running different/temporary speaker wire to the speaker selector eliminated the noise in all configurations.

Very strange and a bit confusing how this all played out. I thought that speaker wire was impervious to picking up noise. There obviously has to be an electrical root cause, but it escapes me. Gremlins come to mind though.  

So, now I need run some new speaker wire to the selector. This will need to be run in a different pathway through the basement, which is is good thing, since it will not be in proximity to the "problem" speaker wire.

[garbulky]

Mar 17, 2014 6:27:38 GMT -5 ads said:

Spent some time yesterday troubleshooting the noise issue with the B speaker outputs from my amps using the DC-1 without a separate preamp.

The vast majority of the noise must be coming from the run of 4 conductor speaker wire from the amps to the Niles speaker selector. I ran a temporary/test set of spliced together wires from the amps to the selector, and the vast majority of the noise disappeared.

Before I did this, I noticed that the right channel of the A speaker outputs had some noise relative to the left channel, but nowhere close to the amount of noise with the B speaker outputs. This was the case even with my current Cambridge preamp and a Parasound 2100 I got last week. I decided to change the interconnects from the preamp (tested the Cambridge, Parasound, and DC-1) to the amps, and the right channel noise was eliminated (went from MIT Terminator 2 to some AR interconnects).

Strangely, changing the interconnects improved the A speaker output right channel, but created the high level of noise with both channels of the B speaker outputs with all 3 preamp options. With the original interconnects, only the DC-1 as preamp resulted in noise in the B outputs.

So, ultimately, the combination of changing the preamp to amp interconnects and running different/temporary speaker wire to the speaker selector eliminated the noise in all configurations.

Very strange and a bit confusing how this all played out. I thought that speaker wire was impervious to picking up noise. There obviously has to be an electrical root cause, but it escapes me. Gremlins come to mind though.  

So, now I need run some new speaker wire to the selector. This will need to be run in a different pathway through the basement, which is is good thing, since it will not be in proximity to the "problem" speaker wire.

Did you try my suggestion?