The original coveted analog delay circuits like the EHX Memory Man were actually designed as more practical/cheaper tape-delay simulators, with the modulation sections of the Deluxe version attempting to emulate the natural warble of tape. They were using the limited tech at the time to emulate tape, but the specific characteristics of the BBD chips they used ended up creating its own signature delay sound that is distinct from tape in many ways ( generally punchier and darker repeats that degrade even faster and more gritty than tape).
Actual tape delay is affected by all sorts of different factors since a tape machine is a complex mechanical device and the condition of the motors, heads (playback and record) and tape itself all play a part in the way the repeats sound. Also the different types of tape delay units all used different signal paths- the Echoplex sound is as much covered for its non-linear preamp (which affected both the clean and delayed signal, tightening and brightening the sound) as it was about the tape characteristics, and of course the multi-head design is characteristic of some other tape delays which allow patterned repeats rather than an individual repeat only. In general tape would lose some bandwidth on top and bottom with repeats, which would tend to focus the repeats in the midrange where they sit nicely under the clean signal without overpowering it.
Emulating all of these factors is a level of complexity that only DSP digital modeling as used in devices like the Strymon units could fully try to emulate- that’s not saying that the Strymon stuff is necessarily better or necessary to get a good tape emulation, just that DSP offers the most potential to emulate all the complexity of the medium. Most of the “tape-echo” style of delays on the market instead are just basic analog or rudimentary digital delay circuits with some LFO modulation and filtering on the repeats. There are TONS of pedals using the lofi digital PT2399 delay chip marketed as tape-style echoes, and they can sound really good in particular for the more degraded tape tones but only really do short delays without significant degradation (an issue they have in common with BBD chips).
In other words, “tape echo” emulation can mean all sorts of things these days (for the most part it is just marketing hype) and you really just have to take each device for its own strengths and weaknesses as a delay and see what works for you! I have both a Strymon El Capistan and a Timeline that get used for various things, and frankly couldn’t care less how well they faithfully emulate actual tape (which is a mindset that can drive people nuts with no apparent benefit, same as any coveted thing that gets lifted up to unreachable heights for no practical purpose) as they just do what they do for me really well. I’ve also had a ton of other analog and digital delays in the past that were marketed as emulating tape echo and they often sounded entirely different from each-other and all had their own strengths and weaknesses as well.
