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RM1999 vs 4001S
Posted: Wed Jan 08, 2025 1:14 pm
by Andir
Morning, Afternoon or Evening All
First time post so please be kind. I have what I think to be a RM1999 but is it actually a 4001S.
How do you tell the difference.
Re: RM1999 vs 4001S
Posted: Thu Jan 09, 2025 12:25 am
by cjj
Welcome to the RRF!
As I understand it, the difference is mainly where it was sold. 4001s basses sent to England and sold by Rose Morris are RM 1999. I'm not an expert on these, I'm sore someone who knows more will reply soon...
Re: RM1999 vs 4001S
Posted: Thu Jan 09, 2025 2:41 am
by jps
CJJ is pretty modest.

He described it just fine.
Where are you, and where did you get the bass?
Re: RM1999 vs 4001S
Posted: Thu Jan 09, 2025 9:20 am
by teeder
cjj wrote: Thu Jan 09, 2025 12:25 am
Welcome to the RRF!
As I understand it, the difference is mainly where it was sold. 4001s basses sent to England and sold by Rose Morris are RM 1999. I'm not an expert on these, I'm sore someone who knows more will reply soon...
That's how I remember it being.
If you want it to be worth more, say it's a RM1999!
BTW, welcome and we need pix!
Re: RM1999 vs 4001S
Posted: Thu Jan 09, 2025 10:07 am
by Andir
I am in South Africa so it could have come over with a UK immigration, there were a lot in 60’s and 70’s.
Its serial number is FB480. I looked in the register and there are 2 other Feb 66 with serials FB478 and FB490 both described as RM1999 and a FB477 described as a 4001S but in the UK.
The other thing about mine is it is fretless which I read are special order so I was hoping there could be factory records of it.
Re: RM1999 vs 4001S
Posted: Thu Jan 09, 2025 10:29 am
by Andir
Pictures, I have the neck pickup but the horseshoe is missing
Re: RM1999 vs 4001S
Posted: Thu Jan 09, 2025 10:49 am
by teeder
Awesome!
Is there any evidence of a new fretboard being installed?
Re: RM1999 vs 4001S
Posted: Thu Jan 09, 2025 11:02 am
by Andir
The previous, previous owner is a guitar tech and says not. The neck is longer so it is definitely a fretless. The fingerboard looks like brazilian rosewood but has no markers in front. The side markers are there and shriveled and old.
Re: RM1999 vs 4001S
Posted: Thu Jan 09, 2025 11:04 am
by Andir
Fingerboard
Re: RM1999 vs 4001S
Posted: Thu Jan 09, 2025 12:10 pm
by bassduke49
While there are no absolutes when it comes to Rickenbacker manufactured instruments, it is unlikely that a bass of that vintage would have been originally fitted with that fretless fingerboard. I think that was done by a previous owner. You don't see many early fretless Ricks, but the later ones I've seen had bubinga wood fingerboards with pearloid dot position markers on the face.
Re: RM1999 vs 4001S
Posted: Thu Jan 09, 2025 12:27 pm
by Andir
So a bit of an oddity then.
When I get a horseshoe pick up I can string it up and remember what a bad fretless player I was.
Re: RM1999 vs 4001S
Posted: Thu Jan 09, 2025 1:34 pm
by jps
To my eyes, the fingerboard has been replaced (as Paul mentions above, it is most likely the case here), and looks like a rough refinish to the bass. (certainly, the neck, going by your photos).
Still, it looks like a nice project bass, for sure.

I'd keep it fretless, assuming you play fretless or want to do so.
Re: RM1999 vs 4001S
Posted: Thu Jan 09, 2025 2:09 pm
by Andir
33-1/2" scale, unbound rosewood
fretboard. This bass was a special order only.
This is the info on the 4000FL I found. The lack of dot markers on the face is my concern and does point to a replacment. The scale is 33.5” so the neck is a fretless.
The refin is not good but I am not qualified to say about a replacment board or not.
I’ll need to find a good luthier to take a look.
Re: RM1999 vs 4001S
Posted: Thu Jan 09, 2025 2:51 pm
by teeder
Can you show the whole back of the neck, especially near the nut end?
What about the scale makes you think it was originally fretless?
Re: RM1999 vs 4001S
Posted: Thu Jan 09, 2025 3:33 pm
by Andir
The scale lengths as far as I can gather are 33.25 for fretted and 33.5 for fretless.
I’ll get the pictures tomorrow.
I have strayed somewhat from whether it is a RM1999 or a 4000s though. Any light to be shined on this