The Tanglewoods are usually fair.   I'd be tempted to point the finger at your pickup but it Alastair's sounds similar in may undermine that thought. First priority would be to borrow a different guitar that you know sounds to your taste and an "acoustic amp" and check the borrowed guitar through your rig and your guitar through the acoustic amp.

Cunning thought - offer to host a local "open mic" night and you will get to hear hundreds of guitars through your rig!