Anyone using a Vox VX50 AG with a (really) acoustic guitar?

**RJVB** · 10-12-2025, 08:51 AM

Been looking around a bit more for an affordable compact amp for acoustic guitar - and by that I do mean that the input would come at worst from a piezo UST

... and the strings will mostly be "nylon" ones.

There are quite a few options, including really nice and not-so-compact ones like the Ortega Cone. There's an AER clone with the appealing name Bugera AC60, a more affordable Nux AC-25 that seems interesting, and an even cheaper Harley-Benton "table amp" that seems surprisingly nice for its small size.

In my mind, an amp for acoustic guitar has to have a much more hifi, audiofilish quality than an amp for electric guitar, so I'm a bit surprised that no manufacturer seems to have jumped on the love for tubes that's even been coming back in more democratically priced hifi equipment. Not for their overdriven distortive properties, but for the reasons they're used in hifi equiment (warmer, more natural sound).
Well, maybe you wouldn't really hear that in a controlled listening comparison, but the sales pitch should work

But there's actually (at least?) 1 dedicated acoustig guitar amp that does use tubes, or maybe just a single one: the Vox VX50 AG. I've seen Nutubes used in a high-end portable DAC (Cayin RU9) so they should be able to have the kind of effect you'd want on acoustic sounds.

I haven't found many demos of it on YouTube that make it desirable (or maybe it does excel at boosting piezo quack?). Does anyone here have experience with it, in particular with a nylon-strung guitar? What would you say is the benefit of the Nutube in it?

**Mick-7** · 10-12-2025, 11:06 PM

The Vox VX50 amp is solid state but uses the Korg VFD NuTube, whatever that is.

P.S. - To answer my own question, this amp is solid state, as I said, but its preamp uses a Korg Nutube, here's an article on that technology:
R&D Stories: The Korg Nutube 6P1 | audioXpress

**Alter** · 10-13-2025, 04:49 AM

Get the Bugera AC60, it's a great amp, saying this while having an Aer too.

**RJVB** · 10-13-2025, 09:45 AM

Originally Posted by Mick-7

The Vox VX50 amp is solid state but uses the Korg VFD NuTube

Yes, which is what many hifi amps, "DAPs" etc. do too; presumably tube pedals as well.

**Woody Sound** · 10-13-2025, 11:58 AM

Are you specifically wanting a tube acoustic amp?

**RJVB** · 10-13-2025, 12:19 PM

At the moment I'm just exploring (I don't actually need an amp), and trying to understand why these appear to be so uncommon.

**RJVB** · 10-13-2025, 01:57 PM

Oh, and there's the question if there is any benefit. I broke out my old ART Tube preamp, connected my Cabaret and used an old iPhone with a monitoring app into a pair of studio headphones.

Very tedious to dial in the various volume settings to avoid clipping (output level on the guitar, preamp level that controls the tube contribution on the ART and its output level). There's the expected piezo quack from the UST but I can't yet say if the supposed tube warmth makes it less or actually more apparent

**Mick-7** · 10-13-2025, 02:50 PM

Originally Posted by RJVB

Yes, which is what many hifi amps, "DAPs" etc. do too; presumably tube pedals as well.

No one has used this technology for higher power instrument amps before though, and doubts have been expressed about it's durability. In fact I read one review in which the owner said his amps preamp failed within a year.

Originally Posted by RJVB

There's the expected piezo quack from the UST but I can't yet say if the supposed tube warmth makes it less or actually more apparent

Yeah, I hate that noise, by all means let us know if you find an amp that can neutralize it.