It sounds somewhat neutral or even uninteresting out of the box from the factory... But it is very easy to make this amplifier to sing with minor modifications.
1. Change +B power supply capacitors to 1000uf (factory equipped with only 390uf); the main capacitors of +B are in series, two 1000uf would yield 500uf in lieu of 185uf from the factory.
2. Change the coupling capacitors between the drivers and power tubes to 0.47uf with Sprague or Solen capacitors, capacitors from the factory are only 0.22uf. The coupling capacitor from V1 preamplifier tube to the driver tube can use a better capacitor as well.
3. Use 6550 or KT88 power tubes, if low frequency palpation is desirable. Make certain to increase biasing voltage to 0.55~0.66Vdc for 6550/KT88.
Chinese amplifiers are not bad, they just need some minor modifications...
These changes will make this amplifier singing really well for many years to come...

Thought i would try tubes, however very disappointed with this purchase,
Have tried everything, changed tubes, changed cables , changed wires
All resulting in a flat washed out mid range and or muddy bass,
To be fair ,maybe tubes not my thing

Thought i would try tubes, however very disappointed with this purchase,
Have tried everything, changed tubes, changed cables , changed wires
All resulting in a flat washed out mid range and or muddy bass,
To be fair ,maybe tubes not my thing

I recently purchased this Amp thinking that going back to tubes would be a nice fit with the speakers I am now using. I was using a Classe CAP 150 integrated. I have owned lots of solid state integrateds and seperates through the years from Classe, Bryston, Moon, Creek, Harmon Kardon etc. My only experience with tubes has been with Prima Luna. I owned a Prologue 3 preamp and prologue 7 monoblocks for about a year. With the Primaluna Pre and power combo I was not that successful. I had some JM lab electra 936 speakers at the time that may have not been a good match even though on paper there supposed to be pretty efficient. I knew I was listening to tubes but the sound was too warm and lazy in dynamics. I tryed different tubes and cables but could not get it dialed in to be dynamic and lively. Any how, I was right to think that tubes would be good with my current set up. This Grant fidelity amp sounds amazing. At a $1000.00 it really has blown away my expectations. I can easily say that my system sounds the best it ever has. Depth of sound stage, air, clarity, seperation., no grain. All the cliche buss word come to mind. This to me is quite something since I have owned alot of peices that were alot more money. If you are looking for a preamp under $3500.00 I highly reccommend This piece in terms of sound quality. The movement of chinese manufacturing works for me when you can get this type of gear new at less than used prices on other gear that doesn't sound as good. I am Jamo1 on Audiogon And Canuck Audiomart