Deep Purple · Perfect Strangers · song 1
Knocking at Your Back Door tuning.
Knocking at Your Back Door (Deep Purple, 1984) is in E Standard at concert pitch (A 440), measured by TuneLit from the record.

Measured by TuneLit
At concert pitch
The album's value, measured on the CD.
Deep Purple · Perfect Strangers · 1984
About Knocking at Your Back Door
Knocking at Your Back Door opens Perfect Strangers (1984), the album that brought the classic line-up back together, and it was written by Blackmore, Gillan and Glover. After the introduction the guitar settles into the main part: two-note shapes on String 4 and String 3, moving between the 2nd and 9th frets, often against an open string. It stayed in the band's live set for the next ten years. Blackmore plays it in E Standard.
TuneLit measured the original Polydor CD at concert pitch, and this song reads −3 ¢, inside the measuring precision. So the Tune button needs no offset at all. The check from the audio agrees with E as the lowest string, so a normally tuned guitar fits the record.
Because the main part lives on String 4 and String 3, those two strings decide whether you sound in tune, more than the low E. The Songsterr tab splits the guitar into a main part and several overdubs; start with the main part, which the record follows from the first verse, and add the overdubs later.
Tip: Tune String 3 and String 4 carefully and check the two-note shapes against the first verse.
Step by step
Tune your guitar like the record
- Tap Tune like this: the tuner switches to E Standard, the notes Knocking at Your Back Door was recorded in.
- Turn String 6 to String 1 until each shows ✓ in tune. Knocking at Your Back Door sits at concert pitch on the record, so the tuner stays at A 440.
- Then play Knocking at Your Back Door along with the record: its lowest open note and your String 6 should ring together without a wobble.
Or the other way round
Move the record into your tuning
Rather keep your guitar as it is? Let Play along move Knocking at Your Back Door instead. Add your own copy, for example from your CD (it never leaves your device); the link already says the song is in E Standard. Choose E Standard at A 440 and Knocking at Your Back Door moves down 2 cents, at its own speed. Slow it down or loop a few bars to learn it, and save the result as a WAV file.
Questions
What tuning is Knocking at Your Back Door in?
E Standard: E A D G B E, low to high, at the pitch TuneLit measured on the record.