Reel to reel signal to noise ratios appear low??

I wonder why the S/N spec for reel to reels is 55-70db and yet many say it sounds so good. Can someone please explain. I do want to purchase one to replace my fathers old one.
The S/N ratio of an open reel is in the same general territory as LP playback systems.

Even with CD, which ostensibly boasts a higher S/N ratio, the vast majority of recordings do not use anything close to the available dynamic range.

Look at your typical recording on playback and you'll find the average level is nowhere near the quietest end of the range. I just converted the U2 LP record "October" to digital this evening. In looking at the average recording levels, the loudest songs were about -3 dB while the quietest section of the quietest song on the LP ("October", the 2nd song on the 2nd side) is about -17 or -18 dB.

We're talking a range of 15 dB between the loudest sections of the record and the softest average level.

The sad thing: this would be an =enormous= dynamic range for many modern pop CDs.

Much classical and some jazz material will have a wider range than this, but the net result is that unless you have an extraordinarily quiet listening room, a 55 or 60 dB S/N ratio will leave the quietest end of that range buried in the ambient room noise.

Just remember that many, many very fine recordings that are still revered as outstanding works were mastered on open reels with S/N ratios in the range you mention.

Often, the biggest advantage that the better S/N ratios of digital recording offers is that you get less background noise build-up in the multi-track mix-down process. And even that advantage is often wasted on many of the current over-compressed releases.
Over-compressed tells you why Lp's and reel stuff always sounds better. I have a significant collection of pre-recordered reel tapes that were done for broadcast stations. The source of the recordings were lp's. Since these were done professionally, years ago, they still sound great. They were recorded and mastered without any compression, but they were often compressed when they were actually broadcasted. Most of the tapes are 7.5 ips, dual track quarter inch tape. I have compares some of the tracks of these tapes with their lp, cd and cassette versions and often the reel version sounds the best.
The TEAC X2000R and AKAI GX-747DBX, both of which have DBX Type 1 built in, and can be used, or not used depending on the desires of the owner of the machine. These 2 particular machines have a Dynamic Range of 128 with DBX Type 1 switch engaged. That is better than digital. And my recordings tend to sound so, I must say people are very impressed when I let them listen to my reel to reel recordings. Ray
A lot of it, too, had to do with what the state-of-the-art of electro/mechanical (internal) component quality was limited by in its production tolerances 40-50 years' ago as well.

I mean: a well-known example (in vintage rebuild circles) involves a small-signal gain, TO-92 transistor Hitachi made in the '70s and '80s called a "2SC458".  EVERY AKAI reel deck made between (approx. 1972-1980) is full of them AND: THEY ARE NOISEY AS EVER with their terminals oxidized (now) practically like soot.

Replacing them, for instance, with a modern equivalent called a "2SC1845" having far better frequency headroom extension specs (in addition to: a re-capping done with, say, all Nichicon Muse aluminum electrolytics and small blocking/filtering caps of ruby or metal polyester)....WILL, SERIOUSLY, PUT THE DECK (even just a plain-Jane-ho-hum consumer Akai!) INTO A WHOLE NEW LEAGUE the manufacturer never could've imagined(!).  After all, even though one's average decent three-head/three-motor 1970s Akai wasn't a Scully 280 or Ampex 102: it was STILL a $600 hunk of equipment at the time (during what would've been the midst of a decade-long recession).

I did such a "hot-rodd" to the back-up Akai GX-365D I'd once found at a flea market for $25.  It's a 59lb. machine from 1971 and, as I knew my way around with a soldering iron: I felt there was nothing to lose (I later found NOS Nortronics heads to retrofit onto it and, scrapped the glass ones which always had the worst crosstalk of any brand).  THAT really changed things.

Off of a sine wive generator: it was now able to record from 11Hz to 21Khz at 7 1/2.  With the 15 capstan adapter (since it's a rare 4 speed model): it recorded 11Hz to 25Khz.