This is my first foray into the wonderful flea-powered world of single-ended triodes. The change came about as a result of a major event the birth of my son requiring the need for softer listening sessions without the sacrifice of dynamics.
My previous two-channel system was based around a Conrad-Johnson Premier 11A/B&W Nautilus 805 combination. It was a very rewarding pairing, but needed some volume to really sing. Given my room size (16 x 13 x 8.5), I felt the less is more theory might be worth exploring.
After some hefty reading over on Audio Asylum and email exchanges with several inmates, I decided to take the plunge.
I contacted Jeff Korneff and had him build one of his 45-based single-ended amps. Its output is about 2 watts per channel of effortless sonic bliss. Its extremely transparent and can deliver impressive dynamics given its minimal output.
Terry Cain, from Cain & Cain, built a pair of his Abbys (a modified Voight pipe design) for my less is more system. The Abby houses a single 6.5 Fostex full-range driver, and uses two interchangeable drivers for different listening experiences. A Fostex FE 166e driver is the more aggressive of the two, delivering a very forward presentation. The second of the two, a Fostex FF165K is a more laid-back, softer presentation. To paraphrase Terry Cain; the difference between these drivers is the deep and clear sound of the FF165k, as opposed to the dynamic projection of the FE166e. I like to think its the difference between sitting in the 10th row and being on stage with the musicians.
The room is equipped with two dedicated 20amp circuits - one to drive the source equipment and one for the amplification. Speakers are placed about 2 ½ feet from the rear wall and about 3.5' from the sidewalls. The chair is 10' from speakers, which are slightly toed-in.
Ive found this system is capable of incredible detail retrieval and conveys the emotion of the music better than any other set-ups Ive had in the room.
Gain: 26 dB Maximum Output: 15 V rms Hum and Noise: 100 dB below 2.5 V output Distortion at 1.0V output: less than .1% THD or IMD Phase: inverts phase of all inputs at main output Output impedance: less than 850 ohms Zero Negative Feedback
The 17ls uses a 4ft BC-14G Cryo Power Cord
Jeff Korneff 45SE
Class A Single Ended Triode, using 45 output tubes, a pair of 6SN7 drivers and a 5Z3 rectifier. The amp delivers 2WPC @ 8ohm with zero feedback. Materials used include: - Electroprint output transformers - Hammond 300 series power transformer - Elna Cerifine caps - WBT binding posts - Kimber RCA jacks All wiring is point-to-point. The 45SE uses a 4ft BC-14G Cryo Power Cord.
Cain & Cain Abby
Modified Voight Pipe horn-loaded loudspeaker. Single Fostex FE166e driver with Fostex T90A super tweeter crossed over using Fostex CS 0.68 uF cap w/ 1ohm resistor in series and 30ohm resistor in parallel.
Sota Star Sapphire
Self-Sensing Vacuum Hold-Down System w/ Remote Double-Regulated AC/Vacuum Pump. Balanced Sub-Chassis Hung from Four Point Spring Suspension. Rosewood Plinth. Vacuum/Motor assembly has been modified to include internal dampening sheets and an upgraded power cord.
Graham Engineering 2.2 Deluxe
Unipivot Tonearm with micrometer adjustability for azimuth, VTA, and tracking force.
Lyra Helikon
Output voltage: 0.5 mV Frequency range: 10 Hz 50 kHz Stylus: 0.08 x 0.12 x 0.5 mm natural diamond shank, Ogura PA line-contact profile (3 x 30 um) Cantilever: 0.3mm diameter solid boron
Turntable Isolation Platform. Twelve layer laminate of high-density polymer, multi-density composite board, polymer adhesives and non-resonant primer with six large IsoNode footers.
Audio Points Isolation Cones
1" Brass isolation cones positioned under the CDP, DAT deck and phono stage
MonsterPower AVS-2000
Voltage Stablizer
JPS Labs Digital AC
Replaces stock power cord on the Meridian 588 CDP
Acme Audio Cryo Silver Plated Outlet (20A)
Two cryogenicly treated 20A outlet residing on each own's 20A dedicated circut. One outlet feeds the power amp and one feed the source components (through the AVS-2000)
Homebrew BC-14G Cryo Power Cord
Bob Crump designed power cord using Belden 19364 14-gauge wire, Wattgate 320i and 5266i connectors. All parts have been cryogenically treated.
Bybee Quantum Purifiers
Internally mounted in series to the positive terminals in the Abby speakers (one per speaker)
Joe: Since Mike hasn't responded yet, I'll take the liberty of answering your last question.
The current rating of the powerline indicates what amperage can be safely supplied to attached devices. It refers to the specification of the breaker box, wire guage, and outlets and associated hardware, and represents the level if exceeded at which the circuit breaker will open and interrupt the power flow to maintain safety. What current will actually be drawn is determined by the devices themselves and the conditions under which they're operated.
Providing a higher available powerline current capacity can't hurt you gear under normal circumstances, but won't help either if it isn't needed. Most stereo systems are made up of gear rated safe at 15 amps and operated under typical conditions draw on average comfortably less (leaving headroom for higher peak instantaneous draw). Some 'monster' power amplifiers that under certain conditions could draw more (such as when powering big, current-hungry speakers in large rooms at high volumes) are spec'ed as requiring 20-amp powerlines, which means they'll have differently-configured AC jacks and need powercords with corresponding plugs (the +/- blades are set at right angles to each other, rather than parallel as on 15-amp connectors).
The benefits of dedicated AC circuits in most cases where the attached gear is standard 15-amp rated probably have more to do with increased powerline isolation from other household devices, and maybe an improved quality of wire and jacks than what the builder originally used, than with a 20-amp capacity per se. But the theory is, if you're going to do the job anyway, you may as well go ahead and do it all the way, especially if you might ever want to use 20-amp gear in the future.
Just as a point of reference, my own system has 200-watt tube monoblocks powering mid-sized floorstanders of average sensitivity in a mid-sized room, and playing full-range music at the loudest volumes draws an average of no higher than 8 amps from the powerline as indicated by my power conditioner's digital meter. Since the system has never tripped the 15-amp circuit breaker while playing music, I have to assume I don't need 20 amps of capacity. (I can trip it if I switch my amps on simultaneously, due to power-on inrush demand of charging the large reservior capacitors, but of course there's a simpler solution for dealing with this occurence.) In a low-powered/high-efficiency system like you propose, the demand is probably even less.
BTW, if the reason you're asking this question here, rather than of your audiobuddies who're recommending the 20-amp lines, is by any chance because they can't answer it, then you may want to take that into consideration when they offer their advice. And though I could never contemplate doing what you've done -- spending a bundle sound-unheard and completely changing direction based only on stuff you've read -- I hope you dig your new system, keep us posted!
I have a battery-powered phonostage myself, the Camelot Lancelot, but it uses two larger, sealed lead-acid batteries and recharges them continuously when not playing records (the battery/recharger and preamp are two separate units connected by umbilicals), which are supposed to be good for up to 10 hours playing time on a full charge. I believe the PhD uses a greater number of regular alkaline cells (C or D?) and lacks an integral recharger if I'm not mistaken, but is supposed to be good for a much longer playing time before requiring new batteries. I'm curious what Sutherland says about the possibility of using high-energy NiMH rechargeable cells with an outboard recharger for when the batteries wear down instead of disposables, given the slightly lower voltage of the rechargeables.
Dude! Sorry not to followup yet on my drop-by threat (we were gone most of August). If it sounds half as nice as it looks you're doing very well for the money - and anyway I see the Professor approves. Curious to know what you heard when powering your new speakers with the old CJ amp vs. your new SET's...
