Pearl F-605 Electro Echo Analog Delay

What is it?
Pearl Model F-605 Electro Echo Analog Delay, made in japan around 1977-79.

Saw this unit for sale and couldn’t help myself. Even if it meant that i was to eat dry bread for the rest of the month. Price wasn’t too bad, and i wouldn’t sell this for the price i got it – never. As analog delays come, this may be one of the greatest. It has input and output level selectors, which make it usable with synthesizers and other devices with line level output. In/out level settings depicted in the photo above work reasonably well with electric guitar.

Three modes on the right are Delay, Chorus and Duplex. Duplex, like the name suggests, mixes both delay and chorus together, resulting in quite spacious soundscapes. Unit runs on 12V DC supply or two 9V batteries. The latter seems to be quite a standard for these older designs. The photo below shows the circuit board. It’s pretty crammed…

But the traces are neat and the design looks pleasing. That box could have housed a bigger board, but i do find this tightness intriguing. Board designer shows some great disipline. I didn’t take the pots off, so you’ll need to live with a shot of raised board. Yup. It is crammed.

The chip responsible for the delay is MN3005, a 4096-stage long delay BBD (Bucket-brigade device). I know i should dig deeper to the design to see what’s really happening in there, but this seem quite complicated analog delay device to begin with. I may have to start with something a little more straight forward.

Anyway. As a closing, here’s a shot of the bottom plate. Everyone will get what the text means, but i think that grammar beats even mine.

How does it sound?
One of the best analog delays i’ve played with. Versatile design that has useful modulation section. Not really sure if these units were meant to be guitar effects in the first place, but it works and sounds.. Well. Analog. Overall, analog delays have their own character which is in many ways worse than modern PT2399 or otherwise digital based delays. This one has cool vintage clang to it, which is not too bad. Unit may be collectible, but i can already see myself using it next time i’m in studio…

UPDATE! There’s a traced schematic up at Freestompboxes (for those who have an user account). This shows there’s no regulator at the power supply side. On battery use, the unit uses 18V, but the dc jack has 12V 300mA printed next to it. This being said, the unit sounds awesome on battery and a power supply that gives 15V and >100mA out. Since the batteries can handle about 20 minutes of use and 12V supply sounds like s**t, i’m under impression that the label next to DC jack is in error. If you have one, feed it with 15V supply and be amazed.