Description

Analog 2-Channel Stereo System to Complement my SOTA 5.1 MCH System and to experiment with.  Phono, line stage preamp, and Sony VFET power amp are all DIY built by me.  Great fun and It sounds wonderful. 

Added TWO new speaker systems this year: 1) a pair of maggie LRS's (with tan Outlaw Audio subwoofer for 50 Hz and lower.  Whoa -is this baby good !, 2) a Pass SLOB open baffle with a Cube Audio FC8 8" full-range, and an Eminence Definimax 15" slot-loaded woofer to augment the Cube.  Jury still out on this one. It is bi-amped with a dedicated Pass crossover.  Could be EPIC.  I also added two amps: a First Watt J2 SIT amp, and a Dynaco / Radial Engr. ST-70 Series 3.  Both are terrific.
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Room Details

Dimensions: 12’ × 16’  Medium
Ceiling: 8’


Components Toggle details

    • Denon DP-75 with Jelco Tonearm and Ortofon Synergy SPU MC
    Ancient Denon DP-75 DD turntable with Jelco SA-750DB removable headshell tonearm, and Ortofon Synergy SPU MC cartridge - musical bliss !
    • PassDIY Pearl 2 Phono Stage (DIY Kit)
    Wayne Colburn's second DIY project.  Toshiba JFET-based solid state phono preamp.  Similar to the terrific Pearl 1 but with a higher gain second stage.  I modified the second stage feedback loop using a 4PDT switch on the back panel to change the feedback resistor values.  

    Sounds very much like my Pass XP-25, but not quite as "bank vault" quiet.
    • Alesis ML-9600 MasterLink
    Digital HD/CD sound recorder.  Allows me to create CD's of my LP's for use in the car, office, etc.
    • Blusound Node 2i
    High Definition Streamer for Qobuz, Tidal and Internet Radio.  Coupled to Meridian Direct DAC.  Works great and, with Qobuz provides for 24 bit / 96 Khz streaming of hundreds of thousands of music productions !  Great streamer, easy set-up and outstanding GUI which is controllable via iPhone.  What's not to like ??
    • Meridian Direct DAC (formerly called Director)
    Compact DAC with SPDIF inputs.  Used to do "proper" apodizing D/A conversion for all digital sources in the system up to 24 bit / 96 Khz sample rates.
    • John Broskie (Glassware Audio) Aikido (DIY Kit)
    Aikido tube-based line stage - provides ~15 dB of gain with four 6DJ8/6922 miniature triodes.  Very quiet and musical sound.  Uses ALPS RK40 volume and balanced pots, Grayhill MIL-quality selector switch and regulated heater and B+ power supplies.
    • First Watt First Watt J2 Power Amplifier
    Pass SIT Static Induction Transistor (SIT) single-ended power 30W stereo JFET amplifier.  I will NEVER sell this amplifier - absolutely the best sounding amplifier I have ever heard.
    • PassDIY Pass / Sony VFET amplifier (built from scratch using Pass's 2016 article.)
    Stereo Class A VFET amplifier of about 20 watts/channel.  Best solid state amp I've ever heard !  Clips softly like a tube amp - perfect match to the Spendors.
    • Pass Labs Aleph-5 Power Amplifier
    Pass Class A single-ended MOSFET power amplifier.  60W stereo - best MOSFET amplifier ever made.  Only out-gunned by the SIT and VFET designs, BUT the Aleph has more power !!  This one  works spectacularly well with the maggie LRS's.  Match made in Heaven !
    • Dynaco / Radial Engineering Stereo 70 Series 3 Tube Power Amplifier
    Classic 35W / channel Ultralinear EL34-based circuit.  Improvements in the power supply, output transformers and input circuit.  Uses a single 12AX7 input stage and L&R 12AU7 driver stages.  This is a throughly modern tun=be amplifier that competes with the best of them.
    • Magnepan Little Ribbon Speaker (LRS) + Linkwitz LX521 Dipole Subwoofers + miniDSP Xover / EQ
    Magnepan's terrific new ribbon speaker (mini-Apogee) crossed over at ~60 Hz to a stereo pair of Linkwitz LX521 dipole woofers provides all the beauty of the BIG Maggies's without all the attendant room placement problems.    The best planar speaker I have heard since I sold my Quad ESL-57's they are really that good, folks !
    • Nelson Pass Designed Slot-Loaded Open Baffle (SLOB) with a Cube Audio FC8 and Eminence Definimax 15
    New DIY loudspeaker designed by Nelson Pass.  Bi-amped using a Pass FW J2 SIT amp on top and a Pass Aleph 5 on the bottom.  This one has a 1/2" thick clear acrylic baffle board with both acoustic and aesthetic advantages over a plywood baffle.
    • Spendor SP-1
    2 and 1/2 way classic loudspeakers with magical midrange !

Comments 4

Hello
Just noticed your system.   I have no ability for DIY building unfortunately for me, but still find your system intriguing. I am curious about your speakers.  Did you build those too to a design by Nelson Pass?  And if so where might I find more information about it.
Thank you

agriculturist

Thanks for the detailed answer. One of these days.......!
~Oran

oranfoster

Owner
Yes, I built them both.  I used circuit boards and semi-conductors provided by PassDIY and Glassware Audio, (John Broskie's company.)  Both websites, along with Pass's FirstWatt and DIYAudio, are great places to go to learn about audio amplifiers and to get help and inspiration to build your own gear.  Highly recommended.  

DIYAudio also has a store where you can buy a number of PC boards, parts and nice HiFi 2000 chassis's for any number of projects.  The articles Pass and Broskie publish include the audio circuits, power supplies and Bill of Materials (BOM), so you can source everything else you need from Digikey or Mouser who both have extensive on-line catalogs of electronic parts of all kinds.

I am in the process of building two new Pass Class A power amplifiers, a Pass / Sony VFET stereo amplifier which is similar to Nelson's FirstWatt J2, and an F5 Turbo, which is similar to Nelson's FirstWatt F7, a simple but very high quality MOSFET stereo amplifier.  I am keeping my Aleph 5 to see how well these amps compare to a single-ended Class A amp.  Nelson has indicated they should be comparable or better, being newer designs.  I have to say, however, the Aleph 5 is a very sweet amp and seems particularly well-matched to the Spendors !

dcbingaman

What an intriguing and wonderful stereo. Did you assemble the two kits? If so, I'd love to know a little about your experience building them and more about their sound. I've always wanted to build some kits, and I even earned an Amateur Extra Class license mainly to fill in my knowledge of electronics so I could build kits with more confidence..... but I still haven't!

oranfoster

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