When does one need a headphone amp? I have some Shure 1840s, which are great, but I’ve read about headphone amps and want to be sure I am getting the most from the cans. I currently have them fed from the phones output of my Mackie desk — should this be sufficient?
SOS Forum post
SOS Technical Editor Hugh Robjohns replies: Really, this is the same kind of question as “When does one need an expensive mic?” or “When does one need a high-end mic preamp?” In the majority of cases you probably don’t ‘need’ a better headphone amp from any practical standpoint. On the other hand, once you can perceive any beneficial improvements or changed characteristics from using that kind of equipment, you’ll find that it quickly becomes essential!
Like any electro-mechanical device, headphones can be tricky to drive accurately under all conditions. A ‘proper’ headphone amp has been carefully optimised for that role, and is usually a stand-alone device with more elaborate circuitry than the simpler and far more cost-effective headphone circuitry found in most compact mixers and other hardware. In general, these cheaper designs are simpler and can struggle to supply adequate voltage/current to meet the most demanding excursions of high-quality headphones. This usually results in slightly compromised dynamic range, distortion and sometimes noise-floor performance, as well as possibly curtailed LF response (again, usually because of limited current capability).
I have, and use regularly, headphone amps by Grace, Crookwood and Benchmark, and they’re all superb. For convenience, though, I often also use the headphone outputs of CD players, compact mixers and so on. Can I tell the difference? Yes, I can. Is the difference so significant that I can’t work effectively? No!
Like most things in this business, you can spend a shed-load of money on a headphone amp and you will probably perceive slightly better detail and clarity from your headphones. But whether that ‘investment’ can be justified in an improved standard of mixing or recording, only you can decide. If you spend a lot of your time mixing while monitoring via headphones, then a headphone amp might be a worthwhile investment, but do try before you buy. If you just use headphones as a cross-check after working on speakers, then it might be wiser to invest your cash in better room treatment or monitors first!