Best Tubed Preamp For A Warm, Rich Sound, Yet Still Detailed and Agile

If you have not had a Direct Heated Triode preamplifier,, it is thr purest sound you 
Will find . After having  every type. This is the most direct type without question ,
Single ended. I am using a custom Lundahl based 4P1L Vacuum tube 
Preamp.  For 1/2 your  $6'k budget  you can best preamps are 3-4 that in resolution and refinement, Radu Tarta is one of the best engineers 
I have ever met .p.s just look up this tube it is probably the most linear Vacuum tube for  music ,just research  the 4P1L  Vacuum Tube.

There is a Doshi Alaap that recently listed on this site. $5995.

nightfall
Best Tubed Preamp For A Warm, Rich Sound, Yet Still Detailed and Agile. I do not want slowness, or lack of detail, however.

As a starting point, I suggest you look for a tube preamp that has low output impedance, something below <1kohm (<1000ohms) 20hz to 20khz, as that will ensure it can drive comfortably any poweramp input, even if it’s 10kohm input impedance, without any added colourations, eg: fatness/thickness/thinness, slowness, rolled off.
Then pick your choices from there.

You could even though it’s much cheaper than your budget, for a trial period try the Schiit Freya, remote control, passive, active s/s, or active tube, balanced or single ended, if you don’t like it you can send it back.
http://schiit.com/products/freya

Cheers George

deHavilland UltraVerve. Wish I still had mine. So good. Outstanding resolution and detail, big tone and can boogie.

Cheers,

Scott

nightfall 

You have enough in your budget to get the deHavilland Mercury 3 which is an upgrade over the UltraVerve which is an exceptional preamplifier. I was a dealer for them for about 12 years and we had a room together at the Rocky Mountain Audio Fest in Denver. Deliriously good. 

http://www.dehavillandhifi.com