Ah yes. Well in Munster (when I say listen here, I mean the Munster recording, as I don't know the other dialects well enough):

For broad R there is:

1. The main broad R sound, heard in Cara, Corp, Cor, Grá, Crocán, Draum (dream in other dialects).
Bárr and Beárna here show it quite strongly:
http://www.fuaimeanna.ie/en/Recordings.aspx?PhonemeID=47

It is a tap, with the back of the tongue raised.

2. This same sound but without your voice being on. Usually happens where the spelling has th (or 'f' for verbs) and r next to each other.
A thrá and bearrfaidh here show this:
http://www.fuaimeanna.ie/en/Recordings.aspx?PhonemeID=23

3. This one I only think is in Cork. It is like the slender r, buzzing sound, but with the back of the tongue raised. You would here it in Rí or Rian in Cork. It is in a few words starting with R and a slender vowel. Listen to Rian in this file from the Cork Irish website:
http://ia600807.us.archive.org/15/items ... BroadR.mp3

4. Number 1, but without the back of the tongue raised. Occurs when r is said before slender t,d,l,n. Like Cúirt. See here:
http://www.fuaimeanna.ie/en/Recordings. ... tho=cairde


Slender R:

1. The main slender R sound, the famous buzzing one. Listen here:
http://www.fuaimeanna.ie/en/Recordings. ... onemeID=48

Abair is very good for the sound.

2. This sound with the voice turned off. I was reprimanded by a very stern five year old for this one! Again this sound occurs when you see slender r next to th (or f for verbs) in writing. I was corrected on the very common uirthi.
http://www.fuaimeanna.ie/en/Recordings. ... onemeID=24

Listen to a thréad.

3. This is like the broad R, but with the front of the tongue raised rather than the back. It occurs when slender R comes after another slender consonant (except t and d), like breá.
http://www.fuaimeanna.ie/en/Recordings. ... =48&Page=2

Listen to bris.

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The dialect I use is Cork Irish.
Ar sgáth a chéile a mhairid na daoine, lag agus láidir, uasal is íseal

When you think about it, l n and r (and to a less extent, slender t and d) are more unstable as they have so many allophones while others show far less. It's an example to where languages can change on an unconscious level, as phonemic distinctions are rather stable while allophones vary by age, region, gender and context

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