i recently got a case of TDK D120's. they were supposed to be B60's but due to seller error i ended up with D120's and i'm just letting the whole deal stay as it is since its a church and blah blah. i really wanted the B60's.

i've always heard c120's are trouble in portables. last night i recorded one on my home deck and played back about 20 minutes of it on my sony WMF1 without any problems. i'm going to play the rest of the tape through today and see what happens but i'm not trusting it.

what are you guys opinions about TDK D120's on portables? i bought these to use on my 1st gen walkman style portables and vintage boomboxes.

I have used 120`s in the past, with no problem, but, generally, i didn`t like any tape above C-100, which boots used to do, and, are still going strong, after20+ years. Just give the 120`s a rew/ff, before use.

never bothered with anything above 90
I do have a Memorex 120 tape (which I got around 1984) - and it sounds fine and never had any issue with it

But for peace of mind keep it short

Back then, the dire warnings about using C120s scared me off. Nothing above a 90 for me for years.

Then, TDK started doing C100s & due to longer albums on CD, thay became very useful at times. Never had a problem with a C100.

I do have a couple of C120s (TDK D & AD) & they haven't given trouble. The lack of confidence in them is always in the back of my mind, though.

Were we brainwashed? Are C120s no good?

No idea 

I don’t use anything above a c90 as I don’t trust them not to break.  

I have 2 120 tapes, one of my first tapes, taped by my brother in law, lots of music

will go on there, but when they get a bot older like 25 years plus they tend to turn

a bit heavy

Whats the bad deal with 120's ?

With a longer length of tape, there is potentially an increased amount of friction due to any tape sitting unevenly on the reels. Also, to fit tape of that length on the reels, the tape has to be made thinner than it is for C60s, C90s etc.

These together means playing back the tape is more likely to stretch the tape if the supply reel is sluggish. Also, if a deck is struggling to turn the take-up reel, the tape will spill out of the cassette & be damaged.

A C120 is near the limit of possibility for a cassette, so there is an increased risk of failure.

C120’s are marginally thinner than C90’s and a lot thinner than C60’s and C46’s.

Being thinner they are more likely to stretching and breaking.   

well things turned out for the better. i met with the guy that sold me the tapes and he made good. i swapped out 150 of them for c92's and only kept 50 of the 120's. i didnt want the 120's in particular but its not a big deal.