# Electronics: Boosting Headphone Output **URL:** \ **Category:** Factual Questions\ **Created:** [February 23, 2006, 3:02pm UTC](https://boards.straightdope.com/t/electronics-boosting-headphone-output/345787 "2006-02-23T15:02:38Z")\ **Posts on this page:** 13\ **Page:** 1
**Author:** ![Mindfield](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mindfield/32/19759_2.png) [@Mindfield](https://boards.straightdope.com/u/Mindfield)\ **Post date:** [February 23, 2006, 3:02pm UTC](https://boards.straightdope.com/t/electronics-boosting-headphone-output/345787/1 "2006-02-23T15:02:38Z")
Right, so I recently got a pretty good deal on a now-discontinued Olympus m:robe 500i 20gb MP3 player/photo viewer. By all accounts, a slick little unit if you ignore two factors: It has less than stellar battery life, and its headphone volume output is crap. When I say “crap” I mean if you’re using “featherweights” per the manual’s reccommendations (earbuds, lightweight on-the-ear phones, anything low-impedence) then at full blast, you get a volume level on the quiet side of “comfortable.” If you’re more of an audiophile as I am and you use consumer-grade studio monitors with heavier-gauge wiring, you get a volume level on the loud side of “What? _WHAT??_ Hello?? Music??” I have never in my life had a device that limited so much power to its headphone jack that the type of headphones used actually made a significant difference in the volume level. Now, I’m no electronics wiz. I’m no stranger to a soldering iron, but we’re not exactly drinking buddies either. I’ve pulled my share of ICs and did simple mods to bits of hardware before modding hardware was cool. But nothing that ever required a resistor chart or anything like that. So, having admitted my electronic suckitude, yet being desirous of embarking on another hack job just the same, I come to the dopers to elicit some possibly factual information\* or some useful advice\* (I’m not sure whether this makes it GQ or IMHO but I figured it’d end up in one or the other anyway so here it be) on such a project. My instincts, hampered by ignorance though they be, tells me that there must be a resistor or series of resistors or some other restrictor limiting the current to the headphone output. I imagine this was done to limit the battery suckage on an already sucky battery, but that’s irrelevant to me. I want to reduce the limitation. Yes, I know I could just buy an in-line battery-operated headphone amp, but I’d like a more permanent, less battery-consuming method. I haven’t opened up the unit yet (though that’s a trivial matter involving four small Philips-head screws) to take a look at what I’m up against, but before I did I wanted to find out if there is something I should be expecting to see that might give me an indication of where and on what sort of components I’ll be performing my butchery. I imagine I will probably be dealing with surface-mounted resistors which is going to be fun in and of itself, but I’d prefer to mentally prepare myself before facing the physical aspects so I know what I might be looking for. - I am aware of the potential risks involved and that I may just end up frying my hardware. I may choose as I see fit to use or discard information given to me as it is my job to further research such things before attempting to implement them, therefore I assume full responsibility for the outcome. Just don’t go telling me to stick my tongue on the battery terminals, okay? ---
**Author:** ![Leaffan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/leaffan/32/299_2.png) [@Leaffan](https://boards.straightdope.com/u/Leaffan)\ **Post date:** [February 23, 2006, 3:30pm UTC](https://boards.straightdope.com/t/electronics-boosting-headphone-output/345787/2 "2006-02-23T15:30:24Z")
I wouldn’t even attempt it. Even if there are identifiable series resistors, by shorting them you would be increasing the output current in a manner that may overdrive the output transistors and cause them to blow. If not immediately then certainly prematurely. ---
**Author:** ![Mindfield](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mindfield/32/19759_2.png) [@Mindfield](https://boards.straightdope.com/u/Mindfield)\ **Post date:** [February 23, 2006, 3:46pm UTC](https://boards.straightdope.com/t/electronics-boosting-headphone-output/345787/3 "2006-02-23T15:46:47Z")
> [@Leaffan](#): > > I wouldn’t even attempt it. Even if there are identifiable series resistors, by shorting them you would be increasing the output current in a manner that may overdrive the output transistors and cause them to blow. If not immediately then certainly prematurely. Wouldn’t that depend on the resistance being eliminated from the series though? I mean if I’m only removing a few ohms from the equation – enough for a 10-20% increase, say – or exchanging a higher impedence resistor for a lower one, then I would think that this would still place it within the realm of tolerance. All things considered we’re not dealing with a whole lot of current here – my guess would be no more than 4.5V and probably 500mA to 1A of draw. Even if something like that may exceed normal tollerance levels for the transistors in question it may be possible to replace them with more robust transistors, no? ---
**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\ **Post date:** [February 23, 2006, 4:04pm UTC](https://boards.straightdope.com/t/electronics-boosting-headphone-output/345787/4 "2006-02-23T16:04:09Z")
People stopped using discrete transistor drivers in the 1970’s. I can almost guarantee you that it has an IC headphone driver, and probably a stereo one at that. The gain probably is set by external resistors. Unfortunately, it’s probably going to be one of these types of little guys: > **[Gaming PC Archives](https://www.pcguide.com/gaming-pc/)** > > We are dedicated to building and recommending the best Gaming PC's for every purpose. Whether you want a budget gaming PC or a high-end 4K video editing PC. Or, worse, it could be part of a surface mount resistor pack on the board somewhere. These parts _can_ be soldered by hand, but it takes a very steady hand and a lot of practice. I’m probably better buddies with Mr. Soldering Iron than you are, and I wouldn’t try it. ---
**Author:** ![Uncommon\_Sense](https://avatars.discourse-cdn.com/v4/letter/u/f9ae1b/32.png) [@Uncommon\_Sense](https://boards.straightdope.com/u/Uncommon_Sense)\ **Post date:** [February 23, 2006, 4:04pm UTC](https://boards.straightdope.com/t/electronics-boosting-headphone-output/345787/5 "2006-02-23T16:04:41Z")
OK, two things before you go any further; Is there volume control on your current earphone set? (usually in the Y part of the cable) Have you tried a different brand of earphones? sorry if that’s too mundane, but you didn’t address either in the OP. ---
**Author:** ![dnooman](https://avatars.discourse-cdn.com/v4/letter/d/839c29/32.png) [@dnooman](https://boards.straightdope.com/u/dnooman)\ **Post date:** [February 23, 2006, 4:08pm UTC](https://boards.straightdope.com/t/electronics-boosting-headphone-output/345787/6 "2006-02-23T16:08:45Z")
It’ll cost a bit, but you could use [this](http://froogle.google.com/froogle_cluster?q=headphone+jack+amplifier&pid=4825516905212651254&oid=1811087086172479986&btnG=Search+Froogle&lmode=&addr=&scoring=mrd&hl=en). ---
**Author:** ![Mindfield](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mindfield/32/19759_2.png) [@Mindfield](https://boards.straightdope.com/u/Mindfield)\ **Post date:** [February 23, 2006, 5:16pm UTC](https://boards.straightdope.com/t/electronics-boosting-headphone-output/345787/7 "2006-02-23T17:16:52Z")
> [@Uncommon Sense](#): > > Is there volume control on your current earphone set? (usually in the Y part of the cable) Not on the headphones themselves. The MP3 player comes with a digital in-line LCD remote with volume control, but it only passes volume functions on to the unit; it does not control volume levels on its own. > [@](#): > > Have you tried a different brand of earphones? Yep. A pair of cheap JVC enclosed headphones; these are of the low impedence variety, but they sound like crap, having almost no midrange and lows that overpower the highs. Then there’s my preferred headphones, a pair of Denon studio monitors, which are higher impedence and therefore don’t pull as much volume. I also tried with the earbuds that came with the unit but they were of such a laughably ill-fitting design that they were a non-issue from the start. > [@dnooman](#): > > It’ll cost a bit, but you could use [this.](http://froogle.google.com/froogle_cluster?q=headphone+jack+amplifier&pid=4825516905212651254&oid=1811087086172479986&btnG=Search+Froogle&lmode=&addr=&scoring=mrd&hl=en) Except those are designed for home use, since they require a 24V DC power source. If I were going that route I’d need a small battery-powered in-line amp. ---
**Author:** ![thirdname](https://avatars.discourse-cdn.com/v4/letter/t/d07c76/32.png) [@thirdname](https://boards.straightdope.com/u/thirdname)\ **Post date:** [February 23, 2006, 6:18pm UTC](https://boards.straightdope.com/t/electronics-boosting-headphone-output/345787/8 "2006-02-23T18:18:35Z")
Have you tried in-ear monitors? I think they’re more efficient than earbuds and cans. ---
**Author:** ![Mindfield](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mindfield/32/19759_2.png) [@Mindfield](https://boards.straightdope.com/u/Mindfield)\ **Post date:** [February 23, 2006, 6:42pm UTC](https://boards.straightdope.com/t/electronics-boosting-headphone-output/345787/9 "2006-02-23T18:42:36Z")
> [@riker1384](#): > > Have you tried in-ear monitors? I think they’re more efficient than earbuds and cans. I keep trying to win a pair of Shure e2c or e3c buds off eBay, just to try them out (I _hate_ buds because they never fit right, but Shure buds come with three sizes of earpieces, so it might be worth a try) They’re not easily available around here, which is a pity given Shure’s long-standing reputation. I’m _very_ picky about my headphones though. If it’s not a name I trust I have to hear them before even considering a purchase. Even with trusted consumer brands like Sony or JVC it’s a matter of listen before you buy, 'cos their sets vary all over the place where sound quality is concerned, even when the dynamic range specs seem to suggest something decent. ---
**Author:** ![Imasquare](https://avatars.discourse-cdn.com/v4/letter/i/5f9b8f/32.png) [@Imasquare](https://boards.straightdope.com/u/Imasquare)\ **Post date:** [February 24, 2006, 12:23am UTC](https://boards.straightdope.com/t/electronics-boosting-headphone-output/345787/10 "2006-02-24T00:23:25Z")
> [@Mindfield](#): > > Except those are designed for home use, since they require a 24V DC power source. If I were going that route I’d need a small battery-powered in-line amp. [These](http://www.dansdata.com/cmoy.htm) may be more suitable, and they are available at fairly reasonable prices on eBay. ---
**Author:** ![Electronic\_Chaos](https://avatars.discourse-cdn.com/v4/letter/e/bbe5ce/32.png) [@Electronic\_Chaos](https://boards.straightdope.com/u/Electronic_Chaos)\ **Post date:** [February 24, 2006, 1:12am UTC](https://boards.straightdope.com/t/electronics-boosting-headphone-output/345787/11 "2006-02-24T01:12:07Z")
> [@Imasquare](#): > > [These](http://www.dansdata.com/cmoy.htm) may be more suitable, and they are available at fairly reasonable prices on eBay. Or you can just [build one yourself](http://www.tangentsoft.net/audio/cmoy-tutorial/). ---
**Author:** ![pikolo77](https://avatars.discourse-cdn.com/v4/letter/p/43a26b/32.png) [@pikolo77](https://boards.straightdope.com/u/pikolo77)\ **Post date:** [February 24, 2006, 4:27pm UTC](https://boards.straightdope.com/t/electronics-boosting-headphone-output/345787/12 "2006-02-24T16:27:11Z")
> [@Mindfield](#): > > I keep trying to win a pair of Shure e2c or e3c buds off eBay, just to try them out (I _hate_ buds because they never fit right, but Shure buds come with three sizes of earpieces, so it might be worth a try) They’re not easily available around here, which is a pity given Shure’s long-standing reputation. I’m _very_ picky about my headphones though. If it’s not a name I trust I have to hear them before even considering a purchase. Even with trusted consumer brands like Sony or JVC it’s a matter of listen before you buy, 'cos their sets vary all over the place where sound quality is concerned, even when the dynamic range specs seem to suggest something decent. Save up for a pair of 4c’s instead. I’ve tried the 2c’s and 3c’s, and they have virtually NO base. I won’t make any friends with this, but the Sony in-earphones (don’t remember the model number but cost $37) are killer for price. I prefer them to the 3c’s. The 4c’s are much more respectable. Someone did a bode plot and showed the frequency response of the 2c’s, 3c’s, 4c’s and 5c’s and it was awesome to see graphed the quanitative difference. Also, it proved i wasn’t crazy that i wasn’t hearing any bass: ) ---
**Author:** ![Mindfield](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mindfield/32/19759_2.png) [@Mindfield](https://boards.straightdope.com/u/Mindfield)\ **Post date:** [February 24, 2006, 5:19pm UTC](https://boards.straightdope.com/t/electronics-boosting-headphone-output/345787/13 "2006-02-24T17:19:06Z")
> [@Imasquare](#): > > [These](http://www.dansdata.com/cmoy.htm) may be more suitable, and they are available at fairly reasonable prices on eBay. I saw lots of those, but they’re still a wee bit bulky for what I’m after; I was hoping for a solution (if it came to that) that wasn’t the same size as my player. I checked out the [Boostaroo](http://www.boostaroo.com/) as a strong possibility, but the price for what I’d need (the one that drives 60+ohm sets) is a wee bit pricey, and the fact that they use AAAA batteries puts me off a bit. (No place around me wants anything to do with quadruple-A batteries, and although Boostaroo sells them at a pretty decent price I don’t want to keep ordering them online) > [@pikolo77](#): > > Save up for a pair of 4c’s instead. I’ve tried the 2c’s and 3c’s, and they have virtually NO base. I won’t make any friends with this, but the Sony in-earphones (don’t remember the model number but cost $37) are killer for price. I prefer them to the 3c’s. The 4c’s are much more respectable. Someone did a bode plot and showed the frequency response of the 2c’s, 3c’s, 4c’s and 5c’s and it was awesome to see graphed the quanitative difference. Also, it proved i wasn’t crazy that i wasn’t hearing any bass: ) No wonder I keep seeing E3cs being sold off in droves by those customer-return-remerchants that are becoming ever more prevalent on eBay. (Aside: 1000goods sucks!) Pity, too – bass is one of my criteria for headphone purchases. (The others being of course, midrange, highs, and range separation) The 4cs are a bit on the pricey side though, especially purchasing on spec. I’d have to really hear then and wear them (like I said, I normally hate buds) before making any decisions. Sonys I tend to avoid these days, but I’ve also been looking at Sennhieser and Koss. (Koss only because I loved the PortaPros; I just prefer enclosed designs these days) Really though I love my Denons. Excellent range (8-32,000Hz) and clean separation through 50mm neodymium drivers. I just need a way to boost volume output from my MP3 player to compensate for the higher resistance of these phones – 'cos I can’t keep using these crap JVCs that sound like you’re listening to music through the other side of a heavy door.