There's no best tube option for 803 except going for tube preamp. You'll be better of with solid state amplification.
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The preamp option seems to be the preferred method based on what I have read, but thought I would explore all avenues. Unfortunately there is no one in KC where I live doing much with tube equipment. Any suggestions on a tube preamp would be most appreciated along with cable recommendations.
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.
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.
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.
The input impedance of the Halo A21 is spec'd at 33K unbalanced and 66K balanced, which would be a suitable match for most tube preamps. I'd still be hesitant to pair it with the BAT preamp, however, assuming the output impedance of the VK-3i is similar to that of the VK-3ix. Although with recordings which don't have significant content in or near the bottom octave you may not notice any issues.
Regarding use of a tube power amp with your speakers, I couldn't find an impedance vs. frequency curve for the 803S. However, impedance curves for several other B&W models, including some that seem to have a degree of commonality with the design of the 803S, all show a rise to very high impedance values (well above 20 ohms) in the upper midrange/lower treble area, around 2 to 4 kHz or so.
The interaction of that kind of impedance variation with the relatively high output impedance of a tube amp will result in greater emphasis of those particular frequencies, relative to other frequencies, in comparison with the frequency response that would occur with a solid state amp. That would seem to be the opposite of what you are trying to accomplish, namely softening the highs.
As others have indicated above, when it comes to power amplification B&W's tend not to be tube-friendly.
Thank you all I at this point I am leaning to the Halo a21 and suitable tube based preamp. This seems like a prudent way to try some tube equipment within my $2500 budget. My Halo dealer will let me borrow their A21 to audition with whatever preamp I pick up. He is also a long time B&W dealer with knowledge of the 803S speakers which will help.
Lastly are there any good reference articles, or books on tube equipment in general, or is it strictly live and learn as you go?
"Thinking about taking the plunge into the tube arena to soften up the highs in my 803S speakers."
The only thing I would suggest is to be aware that you have 2 different goals here. One goal is to try tube gear, and the other is to fix the highs on your B&W's. While you may get lucky, I wouldn't expect a move to tubes to fix the issue with the speakers. Those 2 goals should be dealt with separately.
I drive a pair of B&W 804S with a McIntosh MC275 and love it. I used to have a Rotel 200W SS amp to drive these speakers, and at the time I was looking to upgrade amp I auditioned McIntosh MC252 (250W per channel SS) and MC275 (75W per channel tubed) with 804S, and preferred the 275.
FWIW, bass with the 275 was a lot better than with the 200W from Rotel. Let alone midrange and treble!
Generally speaking, B&W 800-series loves power and hence are usually driven by SS. I remember listening to 802D driven by $30k VTL monoblocks at the dealer and it sounded fantastic...but who would spend that much on amplification for those speakers?
Anyway, my point is with smaller 800-series such as 804S, and maybe 803S, tubes are definitely an option. I would encourage you to consider two MC275 playing as monoblocks. Of course this would not be $2.5k, but you could buy one MC275 now, see how you like tubes, and when funds permit you could buy your second 275. mC275 is also a very low maintenance amp - it is auto-biasing.
Eventually I also replaced my SS preamp with a tube pre (Lamm LL2), which I love too.
In my view, B&W aluminum tweeters and tubes play really nicely together.
Think about it!
Good input from Lewinski. I would add, though, that the output impedance of the MC275 is much lower than that of most tube amps. I had said earlier in the thread that:
Impedance curves for several other B&W models, including some that seem to have a degree of commonality with the design of the 803S, all show a rise to very high impedance values (well above 20 ohms) in the upper midrange/lower treble area, around 2 to 4 kHz or so.The current Mark VI version of the MC275 has a specified damping factor of 22, which is much higher than that of most tube amps, and theoretically corresponds to unusually low output impedances (for a tube amp) of 8/22 = 0.36 ohms for the 8 ohm tap, and 4/22 = 0.18 ohms for the 4 ohm tap. John Atkinson's measurements of the Mark V version are only slightly higher than those values.
So the tonal balance effects of the interaction between the MC275's output impedance and the speaker's impedance vs. frequency characteristics will be considerably closer to those of a solid state amp than will be the case with most tube amps.
Matrix 800 series tweeters were the best around at the time. The 801s and 800 were Stereophile Class A regulars and the 805 was up there too for a long time. Methinks you have something different about your ears ..."
I don't know how you come up with those tweeters being the best available at the time. That's another one I've never heard from anyone. Its possible that your hearing may be rolled off a bit, and/or have some wax buildup. I know a few people like this. They just don't hear the sibilance/harshness that most people hear. As far as Stereophile goes, I think you'll get a better sounding system doing just the opposite of what they say.
This is the only impedance graph I could find, and yes it does look to be tube friendly for good push pull tubes with low output impedance.
But this graph needs to be read in conjuction with a phase angle graph as well, and there are none of these around.
If the phase angle dips to -30 or more degrees at the 3ohm to 4ohm impedance between 50hz and 700hz, which some of the later floor standing 8 series do, then this can then look to the amp as a 2ohm or even lower impedance.
And a tube, even good powerfull one may sound a bit light on in the lower mids and upper and lower bass, and therefore maybe sound too lean and bright overall.
So unless you can find a phase graph, I would stay clear of tubes and even wimpy solid state.
"As far as Stereophile goes, I think you'll get a better sounding system doing just the opposite of what they say."
Wow, why didn't I think of that? Go exactly the opposite direction. So I presume you're a big fan of Bose maybe?
About the Matrix 800 series tweeters, if you care to read more
Quoting the reviewer Larry Greenhill "The 805's tweeter is almost in a class by itself."
Other rave reviews
Yep, these speakers are true MONITORS and will indeed reveal what is in the source material. You need good equipment to match with these speakers -- otherwise you are wasting your time. Poor recordings will be bothersome. And BRIGHT recordings will sound harsh. There is your "ice pick" reference.
I don't blame the speaker for that. Obviously you do. To each his own.
Unfortunately I just don't have the access to the lines required to go forward with moving tubes into this system at this point. Perhaps a recommendation of a dealer specializing in tube equipment could help my local shops are just not very tube friendly.
Also for those reply's suggesting a new speaker to audition I am ALL EARS. I will be upgrading in 2015 keeping in mind I have owned the B&W 803s, 804s, and 805s and have a $6K budget new or used. I will be heading out to the next RMAF and hope to expand my sonic expectations there. I'm looking for a floor standing "British Sound" speaker I guess suited to Jazz and Vintage Rock predominantly listening to Redbook CDs.
Much appreciate any insight along these lines.
This is easy - British sound, $6K budget new/used, for jazz & vintage rock...buy the best pair of Proacs you can find & afford. If you end up staying with solid state, you'll be great. If you end up going tubes, the Proacs will kiss you on the lips.
I've walked a similar path as you...moving up the B&W line, solid state to tubes, exploring new "British sound" frontiers, and I don't think many people would dispute a Proac recommendation at your budget.
(I'd also tell you to look at Wilson Benesch - I have a pair of Arcs and love them just as much as my Proacs, but at your budget it may be harder to find a pair of floor standers. But either way, Proac or WB, I think you'd end up happy, again just from my own experience which sounds similar to yours)
The CJ ET-3 SE looks like a definite option here. Any suggestions on power amps in the $2K-$3K range would be appreciated that match up best with this preamp.
Would my Anthem A2 be suitable until I could find an alternative without clouding the sound of the ET-3SE?
Thanks making some progress on all fronts I think.