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I am slowly getting back into vinyl. I have purchased several LP's that are 180 gram. What makes these better than a standard LP? What is the best LP as far as manufacturer and label? A friend came over recently and was talking about different companies pressing the same LP-but some are better than others. I'm also embarrassed to not know there are 45 rpm albums out there. I know the faster "tape" runs, the better the frequency response. I assume this is why 45's are better and if so, why are there not more of them out there.
180 gram records are about 20 or 25% heavier than normal LP releases. Ostensibly this is an indication that more care was put into the product, though over the years I've had some great lightweight pressings and poor heavy ones. Sometimes the opposite is the case along with a lot of mediocre.

Unfortunately, there are lots of things that can go wrong in LP production that affect sound quality. If nothing else, some buyers get stuck with the LPs from the end of the production run before the stamper is replaced. While some labels are better than others, I've always found vinyl a bit of a crap shoot in the quality control area.

Finally, the reason you don't see more 45s is that physics dictates a shorter play time when the speed is upped. LPs have a constrained play time to start with (and efforts to extend the time affect cutting levels and bass response) so if an artist wants a normal length album, a 45 is out of consideration.
Read Wayne Garcia's survey of audiophile LP companies in this month's Absolute Sound.
I agree with Misstl that the greater mass of the LP record is no garantee for better sound ('speaking' from experience). I most enjoy listening to the Decca/London Phase 4 Stereo records.
If you're into jazz, I've been very happy with the Blue Note re-issues. They average $12-15 each, and sound quite good. They're probably more for music lovers (like me) than for die hard audiophiles. They are not 180 gm. and not 45 RPM. Just normal vinyl albums with outstanding music. Good Luck, and Happy Listening !
Records are a real "crap shoot". If you're a music lover, it's not half bad; but if you're a finicky "analoger", you got problems.
I sgree with Amateur: I own a couple of "regular" London Phase 4 and ffrr label records that I picked up in the 70s. Just terrific playback quality and resolution. Other decent labels are DG and Angel.
I don't find 180 gram or 45 rpm LPs to necessarily sound better. In fact, most don't sound as good as the original pressings. It is really no different with any other format, if the guys making the recording are good we benefit. If they are mediocre we pay for it. It is the same for 33 vs. 45 rpm, IMO. If done right it can sound much better, but it is not a guarantee. Some people hate 45's because you have to get up and change sides more often. YMMV.

I always look for the original pressings. I don't mean low pressing numbers necessarily, just how the LP was first released. Here, the rule of thumb about getting pressings from the country were the lp was mixed has worked pretty well for me. The re-releases are ok for filling in those LPs that are not easily found or can't be found or can't be found for a reasonable price.

I guess what I'm getting to is that if you develop an effective cleaning technique, which you do need to do for new vinyl anyway, you can acquire much more used vinyl quicker and for a lot less money. There are exceptions, but for the most part these heavy vinyl, faster rpm re-releases are marketing gimmicks, IMO.
I agree with Dan.

In most cases 180g, 200g, 45RPM are nothing more than big money grabbers.

And please stop issuing new releases on 2 pieces of vinyl which is another money making scheme.

Put all the tracks on 1 record, thank you.

Quality of vinyl playback as others state is so much dependent of many things. 180,200 gram stuff is not an ultimate guarantor of better quality. The Only area a heavier pressing can give is a lower chance of notable warps from pressing. They also can help make sure the grooves between both sides are further apart and thus less possible to interfere but other than that its not a 100% guarantee to better sound.

Heavier gauge plus better mastering can give you ultimate sound from vinyl. I have found that many of my older and original 1/2 speed mastered discs ca have the most incredible of analogue sound. I have also numerous lighter weight regular discs that have kick butt sound.

The problem with remasters of older music is firstly the condition of the Master tapes. If these tapes were poorly handled and stored there is only so much remastering of them can be done. I'm certain some engineers can do magic with remastering older tapes but there can be no nirvana here. From that how much effort and care was put into the Master disc and stampers has more to do with quality than if a disc is 180, 200 gram or even pressed in 45rpm.

It's much like life you try to find the best but in the end put your faith in reality that sometimes you don't get what you thing you should.