Re downwards expansion & best buy hardware expander;
"GUERRILLA HOME RECORDING -Second Edition HOW TO GET GREAT SOUND FROM ANY STUDIO (no matter how weird or cheap your gear is)" by Karl Coryat is a book that suggests alternative recording approaches to audio recording for those with limited means (hopefully so as to achieve professional quality results). - The use of an Expander is recommended in an innovative application, -not to "fix" anything.
-What I really like about this book so far is that it goes into analogue & digital gear, I.T.B. & old school hardware -the combination of.
In Chapter 1: What is Guerrilla Home Recording? he has a list; "Gear That Really, Really Helps" where it begins ( -I paraphrase
"As you may of figured out, this book is not about upgrading to latest, greatest gear. You can make outstanding rec. using inexpensive or outdated gear; Your ears & approach are your most important tools. -There are a few pieces of hardware that I think are important in creating a good rec." -Then he goes on to list 7 items, "At least two mics, Some kind of mic preamp or mixing board, Direct Box, Compressor, Expander, One good reverb, & One good pair of headphones". -Under "Expander" he states (again I paraphrase) "an expander will greatly clean up your recording by eliminating hum & other noise when no signal is present. An expander is the Guerrilla recordist's secret weapon; people will be amazed by how quiet the spaces are between those huge power chords you rec. A noise gate is a heavy-handed type of expander; not as flexible as true expanders so I don't recommend them" (expanders discussed in Ch. 3 & 4.)
On page 25 in Ch. 2: "Principles Guerrilla Recordist Need To Know" -under "Equalization" -he states, "Equalization is one of of the Guerrilla recordist's best friends, along with compression and expansion (see Ch 4)
On page 53 in Ch. 3 "A Guided Tour Of The Signal Chain" re "Mixer Inserts" he says to the effect, "When tracking I use the insert on practically every signal that goes into my board, using the insert to run the signal through a compressor/expander followed by a 31-band graphic EQ, which is normally set to bypass mode."
On pages 79 - 85 in Ch. 4 "Controlling Dynamics" -"Even with today's inexpensive rec. systems it's possible to achieve a dynamic range of over 90dB. (-from background noise to 90 decibels) Managing the area between these two extremes for each sound you record is a skill that's critical to making a good sound recording. Fortunately there are devices called expanders, compressors, and limiters (called dynamic processors) that help in this task. -Then under "Using An Expander" he states, "A lot of people record without using an expander in the signal chain, and I think that's a shame, because effective use of an expander can do an awful lot to clean up the tracks that you record." -Further he says, Expansion refers to the process of increasing a signal's dynamic range, when audio is coming through the signal chain, the expander may be doing nothing at all, -but when that audio stops coming through, the expander goes to work by lowering the signal further, expanding the background noise floor downward so that there's a larger dynamic range overall, -this is called "downward expansion" - An expander is important in optimizing the actual dynamic range you get out of a system."
-As to, Why not just use an Expander Plug-in?, (aside from the fact that I currently don't work with a DAW or even own a computer) -on the top of page 82 it reads, "LOOK OUT!" re "Real-Time Dynamics Processing Plug-Ins" -"compresssor and/or expander plug-ins available to use within your digital system can be useful in some situations -but unless you have a lot of experience working with *real* compressors & expanders, wherever possible, use hardware versions of these effects instead. -When setting up a signal chain, you need to be able to hear what a dynamics processor is doing in real time -and see what what it's doing by way of indicator LEDs -so you can tweak the unit's parameters before you start recording, (and without your recording system in the signal chain). -Depending on your system, you may not be able to do this with a plug-in, -digital plug-ins are great for a lot of things, but learning how to apply compression & expansion isn't one of them..
More is mentioned re Expanders or Expansion on page 153 re recording Syth Bass & Other Synth Sounds, page 156 re adjusting the expander settings, and page 161 re expansion for voice-overs, pop-culture sound bites, & other sound effects in songs.
As this "Guerrilla Home Recording" is a fairly popular book & expansion a somewhat common practice in audio recording, -surely there'd be someone out there familiar who would know what this is all about.
I'm just trying to determine (apart from a salesperson's perspective) just how much of a hardware expander I should invest in.
-Does any one have an outboard expander they can recommend ?
Thanks for your time & consideration
and cheers' 
