Pass Labs XA25 without preamp (from a variable output source) vs INT25

joeyg- My speakers are Tannoy FSM (monitors) from the late 80's.

That is the million dollar question. When the new INT arrived it needed

200-300 hours of burn in time so at first it was worse. My audio mentor friend

loves it as do I so all I can say with any certainty is what I stated- no improvement.

The Preamp section is said by the Pass people to be "Minimally invasive".

True enough as it has no Pre-out, no sub out. One output & 3 inputs.

@avanti1960 I used extensively passive preamps in the past too (some Audio Synthesis units)  but that is a much more complicated way to achieve nice results than using just a source with high quality variable output into an amp.

With a passive preamp between source and amp you must take seriously some considerations like having a low source output impedance, a low cable capacitance and a high input impedance of the amp (and of course high output and an amp with hig sensitivity). It´s very easy to have a mismatch and get a poor sound with a system with a passive preamp. So unless everything is on set it´s better to avoid using passive preamps.

Getting nice results with a source driven directly an amp is way much easier so if you´ve got bad experiences with passive preamps in the past I strongly suggest to not extrapolate that experiences and  give the "source direct to amp" way a chance, may you´ll like the results.

I

I´d like to say that I´d love to hear that going direct to XA25 route brings spectacular results but I have my worries. A more transparent and pure sound? I´m sure. A "leaner" (cleaner) sound than with a preamp? Of course but as I´ve said I don´t want to get an overall lean sound so here my interest to hear from anyone that have tried both ways with this amp.

I did DAC With digital volume control direct to XA25 and enjoyed it a lot.  But adding a tube preamp did bring more lively and saturated tone and 3D space.

preamps are also very good at integrating multiple sources :)