Saturday 31 January 2015

Roland (Rhythm) TR-77 & Bentley (FR-8L) Rhythm Ace Drum

The TR-77 was Roland's very first drum machine. It was released in 1972. TR stands for Transistor Rhythm. As it is Roland's first drum machine, its place in the history of Roland and indeed in Electronic music history, is assured.

Officially named the Rhythm Tr-77, it was in reality a updated Rhythm Ace  FR-7 &/or FR-8L
The FR-7 appears to be very very rare (In fact I have never seen one in real life or even a photo). More common is the FR-8L  To make things even more confusing, in the UK, the FR-8L was  re-released as the Bentley Rhythm Ace and in the USA she was sold as the Hammond Auto-Vari 64.

 the Hammond Auto-Vari 64

1972 was the foundation year for Roland, who also released in the same year, the TR-33 & TR-55. The 77 was Roland founder's (Ikutaro Kakehashi) baby as he migrated from the old company, Ace Tone. The Tr-77 became Kakehashi's flagship product. 

Here are the TR-77 & the Bentley Rhythm Ace ....... united once again.
The differences between the two machines appear to be small, however they do sound different. The Bently/FR-8L is also slightly shorter than the TR-77.

The TR-77 has two additional patterns (the Western & the 6/8 March) over the Bently.
and also a Samba 1 & Samba 2 rhythm. The Bentley has only 1 Samba Rhythm.

The Bentley has 5 faders for Volume,Tempo, Cymbal/HH/Maracas, Guiro, Snare, Bass Drum.
The TR-77 has 6 faders for Tempo, Fade Time, Volume, Bass D, Snare D, Guiro & Hi-Hat/Cymbal/Maracas.

As you can see from the pics above, these drums were designed to sit on top of an organ.
The wood finish and the built in music stand indicate their designer's original intentions.
However, I think they are the warmest sounding drums I have. I really dig them.
The voices are generated by "tuned resonance" type circuits. Though neither has the kick of a 808, there is a smoothness to both that I truly love.

The Bentley Rhythm Ace (FR-8L)

Both also have that lovely start/stop metal bar that can be seen on their extreme left.
Why don't more drums have this?

The Roland Rhythm TR-77

The Roland Tr-77 Rear

 TR-77. Start, High Impedance & Low Imp outputs.

Here is a interesting video where a Roland TR-8's handclap is routed to an individual out and then run into the Footswitch stop/start of the TR-77. This allows the TR-77 to start and stop on command via an audio signal. The handclap on the TR-8 were placed on steps 1 and 14 of the sequencer and the TR-77's tempo was hand-adjusted to match. 


Both the TR-77 & Bently FR-8L have no sync abilities without modifications.
Nor do they have seperate outs for the individual drum sounds.
 The Bentley Rhythm Ace FR-8L rear

Bentley FR-8L

Bentley FR-8L
These drums are ripe for modding.
Here are some links to start you on your modding and/or circuit bending way.
3. Burnkit2600 TR-77 mods (trigger inputs, External clock Sync,Tone Mods).
4. Warren Cann from Ultravox  (his experiences modding the TR-77)
5. CircuitBenders (FR-8L & the TR-77)
6. Circuitbenders (Tr-77 External Power conversion to reduce hum & background noise)
7. Bently Rhythm Ace with Buchla & Euro (using a envelope follower to sync)
For more info on the history of Roland Drum Machines click here


  1. Hi!
    I would very much like to know how you manage to sync your TR-77 with other gear!
    Please send link or instruction to

    Best regards
    Svein Welde

  2. do you have any internal guts shots of your hammond auto vari 64 i have pulled one from an organ still trying to determine the foot switch wire i have the rest worked out. Thanks

    1. Hopefully this helps

  3. Hi, i just got tr77 with a hammond purchase.
    I have no need for it, would you be interested in purchasing it?

    1. Thanks for your kind offer, but I already have this machine. Best wishes, j

  4. Hi, in case the TR77 is still for sale, I'd be interested in buying it.

  5. Thanks for your offer. At the moment, its not for sale.