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Best Tube Based Options For B&W 803S Speakers

Thinking about taking the plunge into the tube arena to soften up the highs in my 803S speakers. I currently have an Anthem AVM30 using Genelec speakers in a 5.1 theatre system as well as an Anthem A2 pushing the 803S for 2 channel. I will be upgrading to a 7.1 processor at some point possibly the Marantz 8801 and considering an upgrade to the Oppo 105 as well.

My immediate concern is what would make the most sense and be cost effective in terms of trying out some tube equipment for a 2 channel rig. Perhaps keep the A2 and try a tube preamp, or sell it and try an integrated tube amp. Maybe try some type of tube based CD player using the analog bypass in the theatre processor. My budget is around $2,500 used and I am looking for something easy to maintain.

Comments are much appreciated thanks.

bullitt731
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almarg
9,670 posts
 
You will need to be very careful about impedance compatibility when pairing a tube preamp with your Anthem A2. The A2 has a specified input impedance of only 10K unbalanced and 15K balanced.

The output impedance of the BAT VK-3ix is described in John Atkinson's measurements as follows:
The unbalanced source impedance varied from 7k ohms at 20Hz to 1460 ohms at 1kHz and 2650 ohms at 20kHz, while the balanced figures ranged from a very high 14k ohms at 20Hz to 1850 ohms in the midband and above.
If the output impedance of the VK-3i that was suggested above is similar to that of the VK-3ix, it would be a completely unsuitable pairing, which would result in severe deep bass rolloff.

Ideally the output impedance of the preamp you choose to use with the A2 should be no higher than 1.5K balanced or 1K unbalanced, AT ALL AUDIBLE FREQUENCIES. If only a nominal output impedance is known, which would presumably be at a mid-range frequency such as 1 kHz, to be safe I would suggest an upper limit of around 200 or 300 ohms.

Regards,
-- Al
rlb61
792 posts
 
Aar is correct. Be careful of impedance issues. I use the BAT with an amp having an input impedance of 31K, so no problem there.
rlb61
792 posts
 
Sorry for the misspelling of your name, Al.
zd542
5,339 posts
 
I had the 802's and had the same problem with the highs. The best way to fix the it is to get different speakers. If you really are set on throwing money at the problem, I got best results with a Rowland 112. I tried many different amps, both tube and SS, and the Rowland softened up the highs better than anything else. But I still say get different speakers.
bullitt731 OP
25 posts
 
Thanks appreciate the comments across the board.

I have no problem updating the amp as well and was looking at the Halo A21 if that would be a better tube preamp match, or other suitable suggestions.

Really no interest in replacing the speakers as they are in mint condition. The base and imaging in my application are excellent. I just want to tone down the highs a touch. Also intrigued about experiencing the tube sound.

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