It has never met your system. Here, nobody is new.
The audiophile AI that knows your system. Ask about your room, your gear, or the one channel that went quiet.
Ask about a speaker, a turntable, an amp, a receiver, a DAC, a streamer, or the room, and the answer walks through what to check and in what order.
- Trial
- 3 questions in any rolling 5 hours, counted against your browser. Nothing to sign up for.
- Knowledge base
- About 19,800 passages of repair and setup knowledge, checked before every answer.
- Plans
- Pro is $9.00 USD a month and Studio is $19.00, plus tax, monthly or by the year, and the first 14 days are refundable.
Real questions, answered
The questions that arrive at a bench, with the answers the repair guides give. Every guide is free to read, and the app answers from the same knowledge base.
Protection has latched, and the manual gives you two sensing paths to work separately. Current through R789 or R788 develops a voltage that turns on H755 through R783, which clamps the drive: that is the overcurrent path. R777 and R781 form a second network sensing excessive positive center voltage.
Test each path on its own before replacing anything.
The pattern is an output tube red-plating and failing, bias that refuses to set, and volume that dies after a few minutes.
The documented fix: drop the grid leaks to 220 K (one rebuild used 200 K for Electro-Harmonix tubes), double the coupling capacitors from 0.047 uF to 0.1 uF so the RC time constant stays put, and add 10 ohm cathode resistors at pin 5 so current can be read per tube. Roughly 38 mA idle is the target.
It can be. Direct-coupled output, big supply caps: a DC offset fault reaches the terminals. Measure the offset before connecting speakers you care about.
The guide library
Free model-specific repair guides for the receivers and decks a bench sees most. Each is built from the documented failure rows for that model, and an honest guide says what it does not know.
What breaks on a Marantz 2270
Protection latch, blown line fuse, dead FM, DC offset that will not zero, and the 7 Hz relay cutout that is not a fault.
What breaks on a Pioneer SX-780
The PA3004 protection IC, the STK-0050 power packs, DC balance at VR5 and VR6, and the four regional versions that share one model number.
What breaks on a Pioneer SX-1250
The direct-coupled output that makes DC offset a speaker risk, and the shared tuner front end that drifts without a real alignment.
What breaks on a Fisher 500C
Why it eats 7591 output tubes, and the documented fixes for the grid resistors, the power switch, and the selenium bias supply.
What breaks on a Yamaha CR-2020
The heat problem Yamaha issued three service bulletins about, the regulator transistors, the 2SC458 noise source, and the adjustments with their test points.
What breaks on a Sansui 5000A
The corrosive glue that eats component legs and fakes dead devices, plus the protector, bias, and multiplex adjustments.
What breaks on a Technics SL-1200
Pitch fader wear, the D301 zener that drifts hot, tonearm bearings, and the three items a bench should quote on a worn DJ deck.
Pricing
3 questions in any rolling 5 hours with no account, before any of this. Past that, three tiers.
-
Free account
Free
10 questions in any rolling 24 hours, on every device you sign in from. One email, and a password of 10 characters or more.
Make an account -
Pro
$9.00 USD a month, or $90.00 a year, plus tax
150 questions in any rolling 24 hours, plus 5 a day on the strongest model (Pro). Billed monthly or yearly in advance, renews until you cancel, and the first 14 days are refundable. There is no contract, and the card is handled by Stripe.
Start free, upgrade inside -
Studio
$19.00 USD a month, or $190.00 a year, plus tax
300 questions in any rolling 24 hours, plus 20 a day on the strongest model (Pro). Billed monthly or yearly in advance, renews until you cancel, and the first 14 days are refundable. There is no contract, and the card is handled by Stripe.
Start free, upgrade inside
The counter rolls rather than resets: each question drops off the count that many hours after you asked it, one at a time, so a quiet morning gives the questions back.
The complete terms of each tier are in the terms of service. Cancelling and refunds are in refunds and cancellation.