While there are debates as to the specific size and shape of parlor guitars, most will agree that it should be small and comfortable enough to play on your couch or your front porch. Today, the term parlor guitar covers a wide spectrum of guitar styles, from traditional western designs to eclectic one-of-a-kind boutique builds.
The word "parlor" or "parlour" refers to old reception and commerce rooms, and since these compact guitars were regularly played in these small to mid sized venues, they were labeled as such - parlor guitars. Incidentally, the bigger "concert" guitar also got its name from the venue where it was usually played in.
Since there was no legitimate standard for parlor guitar building, luthiers varied the size of their creations to a degree. Even when there is no standard size imposed, many consider having a lower bout that is smaller than 13.5", or smaller than Martin Guitar's "0" shape, to be the historically correct size for parlor guitars. However modern day production parlor guitars don't necessarily follow this size limitation and are much more varied, with some guitar manufacturers labeling even bigger "00" size guitars as parlor, including those with a lower bout of 14". It should be safe to say that "00" size and below are viable parlor style guitars.
An easier way of identifying parlor guitars is by looking at the body shape. If the guitar is smaller than Concert size and has an "elongated" body then it is a legitimate parlor guitar. This longer body is the result of guitar builders trying to increase the volume of small guitars. The luthiers that were building parlor guitars in the past found that by subtly elongating the body, they can increase the volume without expressly increasing the size of the instrument. But now that we have microphones and pickup/preamp systems, some of today's guitar manufacturers no longer deem the elongated shape necessary.
'20s era vintage parlor guitar
Scale and Neck Joint
Scale and neck joint varies widely for parlor guitars, and as such they can not be used as good indicators. Still, small guitars that have the neck joining the body at the 12 fret do resemble vintage parlor guitars better, they are the more popular choice.
Because of their smaller bodies, parlor guitars tend to have tones that emphasize the midrange. This voicing makes the guitar viable for old school blues, slide and folk music, and this distinct tone has helped its current resurgence in today's market. The sound of the different parlor guitars vary subtly depending on size and type of wood used, but they should all have that midrangey tone due to the smaller body.
Whether you take the manufacturer's word for it, or you go by historically correct specifications, the bottomline is to find the parlor guitar that is comfortable to you, and inspires you to play.
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