Yamaha Session and SE Guitars The 600 serial no. Models

The 600 series has a lot of model variations and has models which are both SE and Session 11. The 603, the 612 and the 620 are all session 11s and SEs. The 610 I can only find as a Session 11 but then I can find very little information about the 610 so any help would be appreciated. Most of the 600s I have come across are MIJ but I have seen one 620 with Made in Taiwan stamped on it with a serial number which suggests 1991 they definitely don't appear in catalogues that late so maybe some production of some SEs continued in Taiwan past the catalogue dates .

 
The SE 620 Made in Taiwan

The Yamaha Session II 610

 


The only pictures I can find of the 610 plus 1987 Catalogue scan

I have got a little information on the 610 from Yamaha Archives and from the pictures and catalogue scan above. There are 2 models the 610S and the 610SM The S has a Rosewood board and the SM a Maple one and are otherwise identical. They were produced for less than a year in 1987 at 60,000 yen. As the model number suggests and the pictures show it is a single humbucker. It has one control presumably volume and black hardware including an RM11 bridge. It seems odd that as all the other 600s are around the same price anyone would want this very basic version. Does anyone know anymore?

The Yamaha Session and SE 603

A Session 11 603p

This is the three single coil variant of the 600 series. Those of you following the story so far will know that P tends to indicate a non locking vintage type vibrato however the 603p has a RM11 bridge verified in the service manual just when I thought I had it figured thanks once more Yamaha! One thing I have noticed is that the p models in the 600 series all have black hardware rather than chrome but this only applies to the 600 series.

A 603MA with Active pickups and three controls.

* The body wood for the 603 series and the 612 series is shown as Basswood in all the catalogues but the service manual clearly states they are all Alder. The 620 shows as Alder in the manual and some catalogues but basswood in others. However some of the other series have Alder on Basswood so maybe that's the case here.

Yamaha Session and SE 612 and 620 series

These are the variations with Humbuckers and as per the usual Yamaha system the 612s are all SSH and the 620s all HH

Body of an SE 612

It is possible that there are other models in the 600 series such as a 620A but these are all I have come across so far.