ARC SP9 MK2 tubes


I have just upgraded, or thought I did, from a Counterpoint SA3 running through a B&K PT3 series 2 pre into a B&K Ref 4420 amp. I replaced the Counterpoint and B&K pre with a ARC SP 9 mk 2. Speakers are Vandersteen 2CE Signatures. CD is the Adcom 600. TT is a Thorens 160 with a Linn Basik arm and Goldring 1012 cartridge.

I really liked the warmth and lack of grain when I ran the Counterpont through the B&K. I used the loudness switch on to gain bass as my room does not yield solid bass response.

When I put the ARC in its place last night, the sound changed quite a bit. When playing te CD I detect some grain and hardness but the imaging and detail are good. Since the ARC has no tone controls, the highs seem to roll off a bit so I will probably increase the highs on the speakers a bit. The tubes are "Grand Dragon" which I guess must be Chinese tubes. Never heard of them.

For you ARC 9 users, what tubes have worked for you and has anyone heard of Grand Dragon Tubes.

I am thinking maybe the B&K and ARC are not a good match. I experienced similar results when I ran a Sunfire reference pre through the B&K. Do B&K amps only sound good with B&K Preamps?

Looking for advice and opinions..

Eagleman
eagleman6722

Showing 2 responses by slipknot1

I currently have Amperex Bugle Boys in my ARC SP9 MKII. Very happy with the results. Highs out to there, deep, tight bass, no tube rush. I also had good luck with a pair of NOS AEG 6922 that worked well.
The Sp9 MKII has a really high gain in the phono stage of 67 db. It's been my experience thus far that low output MC carts have more than enough gain available to them. A HO moving coil or MM cart may have too much gain unless you open the unit up and swap out a resistor on the bottom of the unit. The stock change only results in a drop of 6 db.

If you use a HO MC cart, you may find that the stepped volume contol does not offer enough change in the percieved volume. One setting not being loud enough, the next click being too loud. One option would be to have the volume modded away from a stepped unit to a continual type.