December 20th, 2020

Decca
  • vinyl1

Mephisto 3146 - He's ready for take-off....

I didn't get on that well in this one, as there were a few clues that gave me a lot of difficulty - and in fact, there are one or two I still can't explain.  Not to worry - either I will figure it out as I blog, or one of our erudite commenters will set me straight.

This one was an interesting mixture of perfectly ordinary words, very cleverly clued, and some obscure bits where you'd better parse the cryptic correctly if you want to get something you can look up in Chambers.  I did manage to have a surprsing number of immediate hits, rather than blundering around trying one vowel after another until I came to it. 
Across
1 Batting Knight run out? That’s criminal (6)
BADMAN - BA[r]DMAN, just biffed at my end, as I NHO the fellow. 
5 Press covering Dublin brothel? Never mind! (6, two words)
SKIP IT - S(KIP)IT.   Evidently, you shouldn't say you're having a kip over in Ireland.  
9 Determination of base amount, materially perhaps including potassium (11)
ALKALIMETRY -  Anagram of MATERIALLY around K, the chemical symbol for....potassium!    That's kalium to scientists writing in the universal language.
11 Make out American child’s apron is comparatively skimpy (8)
SCANTIER - SCAN + TIER. helpfully defined as a child's apron (US) in Chambers...well, not really. 
12 Trumpeter from first-class school ending with Vivaldi (5)
AGAMI -  A GAM + [vivald]I.  A trumpeter of the avian variety.
13 Austrian composer’s especially good line for bass (6)
LANNER - (-b,+L)ANNER, as in banner year.   A composer I have never heard of - whoa!
14 Heads north, going west then east (6)
THRONE - NORTH backwards + E.  I'm not sure what's going on with the plural in the clue and the singular in the answer.
17 Broadcast probing a lot of TS Eliot hammered a gem (9)
SOLITAIRE - Anagram of T S ELIO around AIR, where we're looking at a particular cut of a gem.
18 Cobblers are negative about source of power (9)
GENERATOR - ROT ARE NEG backwards.
22 Shia millions circulating outside take cotton garments (6)
IHRAMS - Anagram of SHIA + M around R (recipe). 
23 Moderation ending after clubs turned out (6)
EASING - [c]EASING, a starter clue. 
24 Deputy head finally married (5)
MATED -  MATE + [hea]D, like a mate on a boat, that is.
26 Could be pop and beer for social gathering (8)
MUSICALE - MUSIC + ALE.
27 Straight people taking cab in anomalous arrangement (11)
HETEROTAXIS -  HETERO(TAXI)S, a brilliant clue.  
28 Charlie and son like black pencil for drawing (6)
CHARRY - C + HARRY, where Charlie starts out as a letter in the NATO alphabet and then turns into the Prince of Wales.
29 School plan alas, missing leaders for streams (6)
NALLAS - Anagram of [p]LAN [a]LAS.  Streams in India, evidently, usually spelt nullas.
Down
1 Lake amidst black rock? (4)
BALA - Not sure here - is it B + ALA?   Somebody will know.   The lake in Wales.  Kevin had the answer - aa is a volcanic rock, so it's B + A(L)A - a perfect &lit.
2 Got off senior’s day for golf (8)
ALIGHTED - A(-g,+LIGHT)ED.   I biffed this one, and then figured it out - a very tricky substitution clue.
3 Tight roommate gets something initially for nothing — the little monkey! (8)
MARMOSET - Anagram of RO(-o,+S[omething])MATE.
4 Bit of Calvin Klein change? (6)
NICKEL - Anagram of C + KLEIN, an &lit because Calvin Klein might have such change in his pocket. 
5 One leader in Tuscany knocks up coloured cubes of glass (6)
SMALTI -  I + T[uscany} + LAMS upside-down.  
6 Cambodia associated with temple climbing plant (5)
KENAF -  FANE + K upside down.  I wasted a lot of time with wat, of course, should have known better.
7 The Roman Empire once shaped inept Capri (10)
PRINCIPATE - Anagram of INEPT CAPRI.
8 Rolls for large property owners, energetic types (8)
TERRIERS - The other one I can't parse - Rolls = Rolls Royce = RR, but unfortunately teliers aren't landowners.   Your turn!  Keriothe has given the correct explanation: double definition, with terrier also meaning the rent roll of a large estate.
10 Headquarters holds leases on one part of Arctic Ocean (10, two words)
BARENTS SEA - BA(RENTS)SE + A
14 Like grammatical analysis? Follow me and Mike (8)
TAGMEMIC - TAG + ME + MIC, a word I should have heard of, but hadn't.
15 Aussie savage fighting with soldiers over girl (8)
WARRAGAL - WAR + RA + GAL.
16 Astringent comment turned on Midwest state (8)
KRAMERIA - REMARK upside down + IA rightside-up, the abbreviation for Iowa. 
19 Enraged about a right to seize and use property (6)
ANGARY -  ANG(A)RY.
20 Cross long and Italian out of position (6)
TIGLON - Anagram of LONG + IT.
21 Pound note in short obsolete? Right (5)
ONCER -  ONCE + R.
25 English town copper drops out of field event (4)
DISS - DIS[cu]S, an English town I have somehow actually heard of.