Biamp Low frequecy amp recommend

I have a tube based system, need a smooth lf amp with High current about 200 into 8 that doubles into 4 ect. Low priced. Ive had krell ect in the past which are great just dont have the $$ after new speaker purchase.
What about McCormack DNA amp?

200 watts and there are several here at Audiogon for sale (no, not by me) around $2K.

Also might consider Parasound Halo, again 200 watts and as little as $1500.00 here at Audiogon.

Good luck with your search.
am right now in the process of adding subs to my vac 70/70 quad 989 system.have arranged to buy a classe ca300 to drive the subs.was looking at classe,older rowlands,McCormack,bryston,any well built powerfull amp with a large power supply.
Eagle amps got tons of grunt as well.
Marsh amps.
by the way what kind of subs are you thinking of?what are your main speakers? and are you going to use an active cross over?are you still going to play your main speakers full range?are you considering remote sub volume?I looked for a cheapish huge integated amp with remote volume first but all good units outside settled on classe with audio synthesis passion to control volume,getting up to adjust volume levels every record will be a pain in the butt.if your going active are you using tubes?
Other suggestions are good and I would also add Aragons.

It's might not be as easy as you think to plug in a different amp as you might think. There have been discussions on biamping before that should be browsed.
Thanks for the replies. Ive Biamped several times before.
When I was running my 801#3 with a krell ksa250, i went to the local shop and for fun I brought home a pair of 565 adcom mono blocks to compare to the 250, The 565 matched the krell stride for stride if not besting it in the lows with speed and control. Of couse the krell kicked it in the ass as far as natural presentation in the mids and highs adcom was steely sounding.Thanks for the replys.
All of the suggestions are reasonable. I would advise looking into the active crossover solution.

BTW........there is any number of "digital" amps that do quite well in the bass region. In fact, that may be what they do best.