Is no preamp the best preamp of all?

I prefer a Preamp over none.

As mentioned quality is key though.

I have conducted experiments running direct from Bel Canto dac3, PS Audio Perfect Wave system and Esoteric SA50 - in all cases prefer the preamp in the signal path (Plinius M8 used to conduct tests)

****dealer disclaimer - I sell all above besides Bel Canto********

Here is Nelson Pass's thoughts on the matter.

http://www.firstwatt.com/pdf/art_b1_man.pdf

The Vandersteen highpass filter is actually not very accurate for my amps. The closest I can get is with the dipswitches at the 100kOhm setting, which gives a drop of about -2.25dB @ 100Hz, and the slope is steeper than it should be. Disappointing for such expensive little boxes. The digital filter is very accurate, but there is the danger with software of it screwing up that's not there with a passive device. I sometimes wish I hadn't bought such fussy speakers.

There are very few great DACs and CDPs with truly exceptional volume controls and even fewer with analog volume controls. My experience in this regards is with the following digital devices, testing them direct to amps and also via preamps: Levinson 390S CDP, DCS stack, EMM Labs, Resolution Audio Opus 21 w/ GNSC mods, Audio Aero Capitol, Esoteric SA-50.

Trebejo s right, they all perform better direct than through a bad preamp. Though, with a good preamp in the system, for the most part they all performed better than direct. But a good preamp is not so easy to come by! Here are a couple of preamps that did not result in "better" performance for ALL of the players: Gamut 3Di, ARC LS16MK2, BAT 5 series (don't remember exact model), Cary SLP Series (don't remember exact model number).

I feel that with the Aesthetix Calypso (w/ upgraded tubes) and also a SF line 3, they all performed better with the preamp.

Based on your (OP) comments, it sounds like you are running through a Pre/Pro or HT Receiver, if that is the case, then I would suspect most any decent (not even great) product is going to sound better direct than going through the processor (even in direct mode).

If you like that experiment with yor Oppo BDP-95 here an even better one. Download a 192kHz 24 bit FLAC FILE ( I have done this with( Carly Simon No Secrets and others)from HD Tracks onto your computer, insert a keychain USB
(at least 4 gig) and plug it into the USB input in the back of the Oppo BDP-95, And listen to an uncompressed,
solid state(no moving parts)memory, 24 bit/192kHz playback
micro music-server.Some of thier files are only in 96kHz,
go for any music you know well in 192kHz the difference is huge. A taste of a High-Rez music server for low $.
The Flac files won't play on itunes, Windows ect. it will on the Oppo 95. Like all audio devices the USB needs break-in and may take a week on re-play to sound it's best.