CD direct to amp vs active preamp

I was just curious as to the various results. Thanks for taking the time to post and share your experiences and observations.

Like Audiotomb, I have a DAC with two different sets of outputs. I can run direct via the built in shunt style stepped attenuators with 4 volts of output available or run into a preamp at line level. I've done both, making all of the "necessary" cable changes along the way, and noticed no discernable differences. Keep in mind that the level of resolution that this system posesses may not be nearly as high as some others. Then again, neither is the money that i've invested in it nor my bank account. I'm simply trying to work with what i have and can afford : )

Since this specific preamp seems to do nothing but add versatility and it is FAR more convenient, i'm going to leave it hooked up. I have several other sources within that system and having a "transparent switchbox" is pretty handy. After all, who actually "enjoys" hooking / unhooking various components ? That is, unless you just picked up a "new toy" : )

My guess is that those that did not like the CD direct approach ran into loading problems. It is my opinion that playing with various interconnects ( and the different impedances that they present ) may have resolved most of that situation. That is, so long as there was enough drive coming out of the DAC section to push the amp ( easily ) to full power in the first place. Unfortunately, one may not be able to swap cables around, do multiple time consuming comparisons, etc.. especially if you are doing all of this on site at a dealer's location.

Since recording levels and amplifier gain ( input sensitivity ) can vary so much, i don't think that some amps ever get the necessary drive level that they should when fed directly from some players / DAC's. I have known a few folks that have tried running "cd direct" and not been able to achieve the desired listening levels that they could with the addition of an added gain stage ( active preamp). This obviously reduces ones' listening enjoyment, as the music may lack drive and intensity.

Between the lack of gain and loading problems, this might account for the majority of "lacking dynamics / tonal & timbre mismatch" situations mentioned. After all, if introducing a preamp into the system makes it sound "better", you have either corrected the above mentioned deficiencies OR added colouration to the amplification chain that is more to your liking.

Before someone gets all jacked up about my last comment, i personally don't think that there is anything wrong with "tilting" the response to your liking. Since we all have to listen to our own systems, i would prefer having one that i can actually enjoy and "sounds good" rather than one that supposedly "looks good" on paper or measurements and impresses others. The bottom line is to set your own personal and system goals and then strive to reach them.

Just by reading some of the various comments on these forums, it should be fairly obvious that many of us "dance to the beat of a different drummer". The nice thing about all of this is that we can compare notes and draw from any / all of our experiences and knowledge as needed. I know that i've learned quite a bit from others and have applied many of those things to my own personal systems. At the same time, i've tried to pass on some things that i've learned along the way.

Hopefully, we can agree that sharing knowledge and experience helps us all out. Whether or not we agree on specifics may be a completely different story : ) Sean
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Hi Sean,

I've read many responses that basically says digital attenuation isn't desireable because you are taking away 1 bit of resolution for every 6 db attenuated.

For now, I am going direct from Alpha dac to amp. I don't have a fantastic preamp, so this is the best method so far. Attenuation is done with a digital preamp, Meridian 518.

I am getting an ARC integrated amp. Most posts I've read claimed their Wadia suffered from lowered resolution at lower volumes. I don't feel I lose any resolution with the Meridian. I'd see if I get higher resolution using ARC's preamp secion instead of the Meridians.

Regarding the gain, I have two dacs to compare. One Sigma and one Alpha. The Sigma is 2.0v and Alpha is 3.5v. I hear no difference in volume between the two when directly connecting to amp, at least not obvisouly so. The Alpha obviously sounds better, but I doubt it has anything to do with the difference in output gain.

Regarding impedance, I don't know how to figure these things out. Before I went direct, I asked some gon members whether Cal dacs can go thru a passive preamp to my Aragon amp in regards to their impedance compatibility. They said I can't because their impedance didn't match. Well, they are working great being directly connecting.

One thing I don't understand is digital cables. I expressed my feelings to Rick at Virtual Dynamics that analog cables sound better than digital cables in my system. He then told me his digital and analog cables are one and the same. He also added digital cables are the furthest behind in terms of technology. My D-60 sounds harsh. I bought it used and burned it in for a week already.

To connect dac straight to amp, my best configuration is to use analog cables throughout; trans to pre to dac to amp.

I hope my two cents help.

there is a simple, relatively inexpensive solution to the passive approach that to my ears outperforms ANY active preamp i have heard....the Placette RVC. at $1000 list price it is within the budget of most folks and only requires one additional short (the shorter the better) interconnect to use in any system. the Placette Remote Volume Control is placed next to your amp(s) and allows any source with sufficient interconnect drive capability to be used direct into your amps without bass or dynamic limitations.

since i have 3 sources i use a custom passive switchbox that allows me to switch sources and mute from my listening chair.

i do think that the passive/active argument is very situational but that in general additional active circuts cannot add "good things" to the signal and that theoretically passive has more potential when properly executed.

I can see and understand both platforms when it comes to the active vs passive debate.

As to passive's or unity gain designs, you will still have colouration due to internal wiring, signal degradation and loss from passing through various components and contacts, be subject to loading problems, etc...

Active has all of the same problems but can increase gain and alleviate many of the loading problems. The key is to find an active unit that alters the signal as little as possible while passing on all of the benefits.

As to a unit that uses a remote control, how much noise do you think is internally generated from the drive motor that rotates the potentiometer, the infra-red or rf based sensor circuitry, the power supply to feed the motor and remote sensors, etc ???? You might as well "go active" as you've got almost as much "junk" within the box. Sean
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Well, here I go with my 2 cents... I have a complete Cello system (Mark Levinson's last "cost no object" company that went out of business and is now being resurrected). Instead of using an active preamp, Cello or otherwise, I use a Cello passive attenuator called an "Etude". The unit has 4 selectable inputs to one output (all RCA). The attenuator (volume control) is the same hand-wound 60 position dial as found on their $20,000 Audio Palette. With the exception of the Audio Pallette, I have not heard any active preamp that I like better than the Etude, and I have tried quite a few! To my ear, active preamps always seem to put a veil over the speakers. The passive attenuator adds no coloration nor removes anything from the music. Providing you have sufficient gain comming out of your D/A (or whatever source you are using) and impediance is not an issue, passive gets my vote! Ken G.