Marshall AS100D 100-Watt Acoustic Guitar Combo Amplifier
Marshall's acoustic series amplifiers designed specifically for acoustic guitar are quite popular and the AS100D is one of their better selling models.
It sports 4 channels with two of them having mic inputs - it can handle piezio and magnetic picups as well as vocal mics.
One channel is dedicated to vocal microphones with a mic preamp with phantom power and an XLR socket so it can effectively be used as a mini PA system.
It's rare to see a guitar amp of any kind so highly praised by owners, and when I was analyzing reviews and discussions about the Marshall AS100D it was quite difficult to find much negative sentiment at all. The nearest thing to an outright negative statement was in the Acoustic Guitar Magazine review which said, "Whilst this is a great sounding amp, it’s definitely intended for stage use. If you want a nice tone for your guitar alone, around the house and practise room, this big lump of an amp is going to stretch your arm far more than is really merited. If, however, you want a good stage amp which can cut it even when you need two guitars and vocals, it might just be the amp for you. At a keen price, too!".
There was one complaint I saw from a reviewer who said that after owning it for a couple of years they went to replace the tweeters only to find that the original one was no longer being produced and the replacement ones required holes to be drilled in order to fit them in - this is not likely to be an issue for most people.
The versatility of the Marshall AS100D is almost universally praised whether it's being used just for guitar, or with vocals in addition, and even when playing MP3 tracks during set breaks. Many of the amp's features were consistently cited positively - one in particular was the feedback control system in the amp which appears to work quite well from all reports.
Importantly, many of the reviewers who gave this amp a high rating were ones that said they play professionally or have been playing acoustic guitar for over a decade, which means these guitarists know what they're talking about.
There was a small amount of negative sentiment concerning the 16 built-in digital effects, but for every negative comment about them there were 2 or 3 more who liked them.
A note of caution: some online retailers erroneously list this as a 50 watt amp when in fact it has two 50 watt channels giving it a total output of 100 watts at full power.
Take a look at the following video demo to see the full range of features and effects: