Hello. I landed upon this site and this particular thread when researching one of the Thomann guitars posted about above. While I don't own any HB guitars (yet), I have purchased 3 or 4 inexpensive Chinese (mostly) imports recently and hoped I could lend some useful info about this and related things. I've alternated between solid body electric (Telecasters mostly) and classical guitars over my 45+ years of playing guitar. I've had formal lessons and do / have owned some good 'professional' quality instruments (Alvarez-Yairi CY140 -- 35+ years old; a top end Ramirez copy essentially). I've owned many, many Fenders and Gibsons and others too.
Regarding the question: Why does the HBO-850 not sound so great? I don't own one, and have never played one -- but, the answer can be uncovered by simply looking at the construction/components used to build it.
Here is the product description from Thomann USA: (asterisk (*) denotes comments I added next to original text of description)
www.thomannmusic.com/harley_benton_hbo_850_classic_natural.htmHarley Benton HBO-850 Classic Natural
Model: Roundback with cutaway
Top: spruce *(implies laminated, not solid)
Body: ABS Super Shallow Bowl
Neck: Mahogany
Fretboard: Roseacer *('roasted' maple essentially; Torrified?)
Fretboard radius: 400 mm
23 Frets
Snow-flake grip boards
Multilayer ABS body binding
ABS neck binding
Scale: 648 mm
Nut width: 48 mm *(almost certainly plastic -- ugh)
Bridge: Blackwood
Open Gear Classic machine heads
Dual-Action truss rod *(can be ok, but if a guitar is built correctly, it should not be necessary)
Strings: HB Medium Tension Nylon *(toss them!)
Pickup with 3-band EQ
Colour: High gloss natural *(lots of finish chokes vibrations of the top!)
The shortcomings of this design/construction, in bullet list form, roughly in order of importance:
(Up front I should add that I recently bought the Thomann Classic S 4/4 and have turned an average 'factory' guitar into something that sounds and plays great -- something more like a $600-$800 instrument, instead of the $120 I paid for it. But, it 'takes some work'.. It is possible you can do the same with a similar type of guitar..
1. Upgrade saddle -- it is not BONE.
2. Upgrade nut -- it is not BONE
3. It is almost impossible that a human took the time to check level, and polish the frets adequately. Check, level (if needed) and polish them well.
4. The finish (on top especially) is nearly always too thick 'choking' resonances of the top. There are ways of incrementally thinning the poly finish to allow the top to vibrate better. This makes a big difference in output sound/volume; generally most true of higher strings / notes.
It is a guitar, not a piece of furniture.
5. The top *appears* to be laminated spruce; glue inhibits resonances/vibrations and never ADDS to it. You can't change this -- you're stuck.
Laminated back & sides are generally thought to be 'ok' nowadays, but having a decent solid top is really critical for decent sound. Buy solid top whenever possible.
6. Break it in sonically -- either play it a lot and/or place it in front of or on a speaker with decent output. Play music through the speaker to vibrate the wood of the guitar. Do it as much as you can manage.
7. Use good quality strings. Ditch the stock ones ASAP and replace with a known suitable brand: D'addario, Savarez, LaBella, etc. D'addario Titanium NT (normal tension) works well with spruce top guitars by my experience and my favorite more 'standard' nylon set is the LaBella 2001 MHT
OK, you probably can get the idea of the things to check. Consider this: a guitar's top is the 'engine' of it's sound. On this HB nylon string, I found the following particularly unnerving: a plastic saddle sitting on top of a piezo wire placed in a bridge made out of 'blackwood' (there is an African Blackwood, but I doubt this guitar uses it; more likely, it is 'roasted' Pinus Radiata [Monterey Pine]), all attached to a laminated top -- sonically, it is a recipe for disaster.