Can anyone explain the 19mm spacing and how this affects a bass? Im considering a 5 STrng Bassmods

That simply means that the space between your strings on a five or six is the same as it is on a four. For a lot of players, fives or sixes with narrower spacing are more difficult to play, especially if they often slap.

 

Dead on Doc

It's the distance between the strings at the bridge.

 

That is important to note because a bass that is wide at the bridge can be narrow at the nut.

 

The doctor is right on. A 19mm 5-string is the only one I would consider, partly because I have very big hands and big fingers and that's where I'm most comfortable. But some players have smaller fingers and actually prefer the strings to be a little bit closer together which if it's not awkward for you, can help you play a little bit faster.

 

Correct that the 19mm refers to string spacing at the bridge.

I believe it is misleading to say that 19mm is a generally preferable spacing. I strongly prefer 17.5mm or 18mm for a 5, mainly because of the neck taper; and I do plenty of slapping. I’m not alone. Many players prefer the narrower spacing on a 5.

Each player must try both and decide for themselves.

 

I have owned and really enjoyed lots of basses spaced more narrowly than 19mm. I like 19mm the most, but narrow spacing like 17 or 17.5mm at the bridge works for me if the neck is not tiny like an Ibanez Soundgear.

 

Right. We all have different hands.

 

The distance from the outside edge of the E string to the outside edge of the G string on both my basses is 6cm. What does that equate to in string spacing?

 

19mm

 

Technically it's the measurement between the centers of each string, not the space between them.
Unless you're using a bridge that allows you to adjust each string left to right individually, there will be less space between the thick strings than between the thin ones.