Is no preamp really better that a good preamp?


Hi All, I have PS Audio gear, and both my DAC and my phono section have enough gain to run directly to the amp. Is this really the optimal arrangement, or might I actually get better sound by adding a good preamp, say a Cary or a Modwright tube unit, to the mix. Thanks in advance.
Ag insider logo xs@2xrustler
I'd prefer it if you wouldn't use my posts to fuel what looks to be a healthy argument brewing here as the above post (by me) is being used out of context :-)

All that aside, my comments, and I think Guido's on filter and upsampling for the Esoteric units are not meant for, and have little or nothing to do with a debate regarding preamp/no-preamp.

While it is true that the K-series Esoteric players (up until the X revision) have a volume control on their outputs, and you CAN skip use of a preamp, having heard both the P/D and K series units that offer this capability used both with and without a separate preamp, my opinion is there is no comparason in sound quality, imaging, sense of air, soundstage depth, accuracy and overall musicality when a good preamp is inserted in the chain (regardless of who makes it). In my case, I owned an Esoteric C-03 for quite a few years and now have a C-02. I've gone bare bones with my prior D-03 DAC and used no pre-amp and heard the K units used similarly; while the results are good and very pleasing, inserting the preamp back into the circuit gave me MUCH more in terms of the above criteria every single time.

This whole thread is subjective, I do realize that,...furthermore, it has everything to do with the choice of electronics, type and quality of interconnects,balanced circuitry versus single-ended, quality of power cords, grounding, etc...in use at every step in the chain. All things being equal, it is hinged on what the listener is looking to achieve, the quality of their hearing and ability to perceive differences in various sound presentations.

There is more often than not, no absolute right or wrong, better or worse, etc...that can be stamped on every possible combination in this hobby of ours. This is one of those topics :-)
this has all been very enlightening for me. Many thanks to all. I think I've decided to get one and see what it does for (or to) my sound. I'm thinking of a Aesthetic Calypso or a Jeff Rowland Capri 2. Any ideas regarding these two units?
Rustler, with the Calypso I would have the concern I cited in my post dated 9-26-15, that its gain (specified as 29 dB balanced/23 dB unbalanced) may be so high that you may forced to use it with the volume control on the DAC set too low to be optimal. That issue is much less likely to occur with the Capri or Capri S2, which have gain specs of 14 dB.

Aside from that, I don't see any technical issues with either choice.

Good luck. Regards,
-- Al
How in g**s name can a active preamp give you more REAL detail (not perceived detail because of distortions) from the source than the same well match direct source to poweramp.??

Please produce some laws of electronics in your answer and not voodoo speak.

The answer to this was in my prior post. However I like to use engineering principles since you asked; we can start there... normally in any situation where we are driving a load, as a general rule of thumb the source will have about 1/10th the impedance of the load. This is a good practice to insure proper bandwidth and low distortion of the source.

When you put a resistance in series with the source, the source will begin to have troubles driving the load. Now when the series element is a volume control, one might argue that the control itself becomes the source but this is not entirely accurate. The source becomes that of the volume control and the original source together, along with whatever effects are imposed by the interconnect cable between the source and the volume control. Many sources use a coupling capacitor at their output; such sources can suffer frequency response aberrations when a series resistance is imposed between the source and the load it has to drive (which in most cases will be an interconnect cable and the input of an amplifier).

Generally speaking, these errors can be reduces if the source is of low output impedance and the volume control is a fairly low value, for example 10K ohms or less. The issue here is the ability of the source to drive such a load, but if that is the case the effects of the cable between the PVC and the input of the amp will be better controlled and the series resistance between the source's output coupling cap and the amplifier's input will not likely impose much of a frequency response error.

When you get into higher source impedance and higher volume control values the cables play a larger role. This is partially due to capacitance. You can calculate the minus upper 3db point by the formula f=1,000,000/2xPi x C x R, where R is the source resistance in ohms, C is the capacitance to ground (that of the interconnect cable) in microfarads and f is the -3db point in cycles per second.

The cable between the source and the volume control should not be ignored.

While the ear cannot detect phase shift of individual frequencies, it can detect phase shift in a band of frequencies (generally as a tonality but high frequency phase shift can also affect imaging), generally phase shift effects can be heard to 1/10th the cutoff frequency, so if your -3db point is at 50KHz, there will be effects down to about 5KHz.

When you put a PVC after a source, as far as the amp is concerned the output impedance of the source is increased, conversely from the perspective of the source the load impedance is decreased. This can lead to the low frequency cutoff being increased in frequency. To avoid phase shift in the audio passband, the cutoff should be about 2Hz as phase shift components (which to the ear sound like a loss of impact) can be heard to 10x the cutoff frequency. So of this moves from 2Hz to 5Hz phase shift components can have an effect at 50Hz rather than 20Hz.

Thus it can be seen that while a PVC is a very simple device, if incorrectly used it can act as a simple passband filter. Keeping the phase shift components out of the audio passband is the key to success and is why they can work so well in some systems but not in others.


we are discussing about what the OP's question is, stop rambling about passives, GET A GRIP MATE.

"Is no preamp really better that a good preamp"

And I also addressed this in my prior post, which (in a nutshell) says that in some cases a passive will be better and in others an active will be better, thus both must be auditioned. I thought you would be happy that I was agreeing with you that passives can work...