Talk:Phone connector (audio)/Archive 1

4/5 conductor jack/plug

Are the four- and five-conductor miniature jacks and plugs readily available? They don't appear in the catalogs I most often use. It's a good point that they exist, but I'm not sure the article as it stands is true. Andrewa 03:04, 22 Sep 2003 (UTC)

Can't say for sure - I know they are featured on the iBook, PowerBook, iPod - maybe it's only an Apple thing... I also have an iTrip made by Griffin Technologies which connects to the iPod, this has a 5-conductor plug protruding from it. I wanted to note the existence of these but make minimal changes to the text, but perhaps the original sentence about availability needs to be moved or changed. GRAHAMUK 03:11, 22 Sep 2003 (UTC)

I've had a go, see what you think. Andrewa 03:59, 22 Sep 2003 (UTC)

Cool :) GRAHAMUK 04:05, 22 Sep 2003 (UTC)

I still feel uninformed about the four and five conductor miniture jacks. I just bought an Imac g5. It has a 1/8th inch jack labeled with a pictograph of headphones and the words "Optical out". Subsequently I have been able to find speakers that are designed to only plug into the computer here, not enter any mixer or amps, and produce 5.1 thx sound. Woah. So that means this little jack just seperated all those channels. Can someone, more in the know than I, educate this page to reflect that? Thanks!

I think thats a combi connector that can take either an electrical 3.5mm stereo jack or a 3.5mm optical (toslink but with a different connector iirc) plug. i often see a red light in the headphone jack on my laptop which looks very similar to that i have seen in toslink connectors. Plugwash 23:26, 9 December 2005 (UTC)

---

There's a separate article Tip ring sleeve (TSR) describing the use of three-conductor jacks and jack plugs in non-stereo applications. In the USA, TRS is a synonym for jack plug. For discussion as to whether the two articles should merge see Talk:Tip ring sleeve. Andrewa 20:24, 12 Nov 2003 (UTC)

Major omission

Of course, you do realise that a lot of those connectors marked as 'obsolete' are still manufactured, and are in extensive professional use in the broadcast and telephony industries? Mmh? e.g. shiny new Bantam (PO) jacks for sale here; http://www.canford.co.uk/commerce/item_43-198_3000351.aspx

why is this an error?

Removed section: "The potential for confusion here is heightened as the RCA jack is also known as a 1/4" phono jack and is mainly used in applications for which the 1/4" jack plug was previously (and also continues to be) used." Why? - Omegatron 20:01, Jul 23, 2004 (UTC)

I agree, there seems to be some weird sort of british bias in the text that implies americans would not use the same language for these. No american would call an RCA jack a "phono jack", they would call a 1/4" jack a phono jack, and possibly the smaller ones too. I guess I'll alter it now. :-) Ace Frahm 00:19, 1 March 2007 (UTC)

Sure some Americans would call an RCA jack a phono jack 'cause that's what they're known as because that's where they were first used. And 1/4" jacks are definitely "phone" jacks to engineers.

Atlant 00:51, 1 March 2007 (UTC)

That makes no sense. RCA plugs are not used for telephony and are not compatible with 1/4" jacks, whether or not they were used anywhere first. If this was ever true, it has not been true for more than 25 years. It might be possible that this is so in Britan, but it is not so within the USA.Ace Frahm 03:43, 3 March 2007 (UTC)

"Phono", not "phone". — Omegatron 19:05, 3 March 2007 (UTC)

History

How did the name "jack" come into use?

good question. probably related to this:

"jack (n.) Look up jack at Dictionary.com

1391, jakke "a mechanical device," from the name Jack. Used by 14c. for "any common fellow" (1362), and thereafter extended to various appliances replacing servants (1572). Used generically of men (jack-of-all-trades, 1618), male animals (1623, see jackass, jackdaw, etc.), and male personifications (1522, e.g. Jack Frost)." - Omegatron 16:21, Mar 29, 2005 (UTC)

-- Uh, well, the plug and socket used to be referred to as the "Jack and Jill." No, really. --132.185.240.120 16:27, 10 August 2005 (UTC)

References? Or hearsay? Seems the sexes are reversed...

Also, isn't "phone plug" much more common than "jack plug"? (It's a UK thing) — Omegatron 02:36, 28 February 2006 (UTC)

I've made some progress on this question. [Edit: skip to 'Update2' below for the short answer.] The answers lie in Google Books and Google Patents. In chronological order:

1855: Invention of the 'spring-jack' (see 1867 item below) by George F. Milliken of Boston, Massachusetts, according to The modern service of commercial and railway telegraphy: in theory and practice, arranged in questions and answers by John Patterson Abernethy, 1887, p.152. To understand why this term is relevant, see the 1889 item below. Note: there are other types of spring-jack, such as a type of clockwork meat-roasting spit, that do not appear to be related to this usage. In the spit, 'jack' was used in the sense of 'machine', not 'lever' as explained below.

1867: US Pat. US385863, the first reference I can find for 'spring-jack', meaning an electrical connector in a telephone exchange. The earliest design was a metal leaf-spring pressing down on a grounded bus-bar. The spring was connected to the telephone line to ground it when not in use. To connect to the line, a 'terminal wedge' was inserted between the spring and the bar. I can't find an explanation of the name, but it seems to be derived from the widespread mechanical term 'jack' meaning 'lever' or 'beam-shaped actuator'. For example, 'jack-wires' were springs used in looms to hold down the bobbins, and a 'jack' is a lever or push-rod in piano and lock mechanisms.

1878: US Pat. US215568. A type of spring-jack is described that mates with a "movable plug or connector … consisting of two concentric hollow cylinders".

1888. 'Jack-plug' appears in The Electrical world, Volumes 11-12, p.301. "telephone H, and a transmitter h, have their terminals connected to a jack-plug P". (Note: this is earlier than the OED's first citation from 1891.)

1889. 'Jack plug' and 'spring jack' appear together in Canadian Patent Office Record, Volumes 17-18, p.301: "A spring jack consisting of two or more severable contact points, an opening or passage to such points for the insertion of a jack plug...".

So I would say that 'spring-jack', the spring-operated contact in a telephone exchange, came first. The thing that plugged into it was variously called the 'wedge', 'knife', or 'plug'. By 1888 it had become 'jack plug'. So any explanation to do with the sexes of plugs and sockets is a red herring, although going back further, 'jack' meaning the spring contact inside the socket might have derived from 'jack' meaning 'cantilevered thing', thus providing the male connotation. 'Jack' meaning 'mechanical device' seems to be a dead end. --Heron (talk) 19:57, 8 October 2012 (UTC)

[Update] (Apologies for using this page as my notebook but the notes are relevant to the history of the component.) Google shows George F. Milliken (d. Oct. 1921) to have been be the manager of the Western Union office in Boston, MA, and Edison's first boss. I have found his name as the signatory some patents and as the inventor on others, so he may or may not have been the actual inventor of the spring-jack. I'm still searching for evidence. One promising reference is Frank L. Pope. Modern Practice of the Electric Telegraph: A Handbook for Electricians and Operators. (New York: D. Van Nostrand, Publisher) 1881. I'm also beginning to doubt my assumption that the spring-jack was the first use of 'jack' in this sense. There could have been other types of electrical jack before that. --Heron (talk) 10:45, 9 October 2012 (UTC)

[Update2] US Patent 243320 'Electrical Switch-Board' by Adolphus G. Snell refers to 'jacks' (without springs). These appear to be the precursors of the spring-jack. The jack is a pivoted L-shaped metal lever that is moved manually to make electrical contact with a wire below. This part looks very much like the 'jack' in a piano or lock mechanism, which is an actuating lever. This is sense 15 of Jack, n.[1] in the OED. I think I have now established a trail from 'Jack', the man's name, through 'jack' meaning a machine that does a man's job, to a lever (straight or L-shaped), to the metal lever used as a switch in early telegraph exchanges, which developed into the 'spring-jack', which became the standard telephone jack. The thing that makes it a 'jack' and not just a socket is the moving contact that makes and breaks the circuit. QED! --Heron (talk) 11:25, 9 October 2012 (UTC)

audio signal standards

Today, RCA jacks and jack plugs are mostly found on audio/video consumer products. Does anyone know the standards for the audio signals they carry (i.e. lowest and highest voltage, dynamic range handling etc.)? - unfortunately i can't find any articles on the internet regarding analogue audio standards. Thanks, --Abdull 14:26, 22 May 2005 (UTC)

iirc from specifications i've read it seems to be about a volt or two peak-peak for line level signals but the specified max varies quite a bit between manufacturers. Plugwash 16:32, 22 May 2005 (UTC)

"professional" gear has a "line-level reference signal" of +4 dBu, consumer gear is -10 dBV. RCA jacks are typically consumer level, balanced 1/4" jack plugs are pro level, others may vary, etc. As far as maximum voltage/headroom above the line level i'm not sure if there is a standard. typical for things i've seen is ± 15 V power rails for +4 dBu stuff, which equals maximum level of about +22 dBu. so 18 dB of headroom above line level. dynamic range depends on noise floor, which varies from unit to unit and should be a listed specification. - Omegatron 18:16, May 22, 2005 (UTC)

Introduce a better link to TRS article about wiring stereo equipment

Uses of jacks

Added "Some Strobe Lights, like the Chauvet ST-2000S use 1/4" Mono cables to sync flashing" under the "Uses" section.

If anyone has any more information on what triggers the strobe to pulse through this mono jack, it would be greatly appreciated. --Electrosoccertux 05:04, 15 January 2006 (UTC)

Move concerns

The proposition to move the TRS page into this one has been on the talk page for the TRS connector article for some time. I just took the time to add the necessary template here. For concerns, please read discussion on the talk page before posting back here. The most viable solution seems to be to move this article to one called "Phone connector (audio/visual)" and merge the TRS connector article into the page. I feel that the rename will remove any ambguity as to what exactly this article refers to, since "Jack plug" seems to be a misnomer (I've honestly never heard of the term "Jack plug" before I read wikipedia and I've been working with audio for ten years now) Please specifically note the discussion at top of Talk:TRS connector on this issue. This will constitue massive rewrites of this article. I'm willing to attempt it, but it will be a time-consuming effort. Thanks. ICberg7 01:47, 28 February 2006 (UTC)

and before i came to wikipedia i'd only heared theese reffered to as a "phone plug" once (and that was on a pack of connectors bought from tandy who had very close links iirc with the american chain radio shack). I get the impression this is a british/american terminology differance (you call them phone plugs we call them jack plugs). Plugwash 01:56, 28 February 2006 (UTC)

The following discussion is an archived debate of the proposal. Please do not modify it. Subsequent comments should be made in a new section on the talk page. No further edits should be made to this section.

The result of the debate was don't move. —Nightstallion (?) 20:55, 6 March 2006 (UTC)

Requested move

User:ICberg7 has posted the following proposed move to WP:RM:

Jack plug → Phone connector (audio/visual) : The term "jack plug" is specific to the UK and is rarely used elsewhere. In practice, a "plug" goes into a "jack." The (audio/visual) was added to the name to differentiate this connector from a standard telephone connector (RJ-11). The term "connector" was added to follow suit with other audio equipment pages (XLR connector, RCA connector). Please see Talk:TRS connector for further information.

---

Please add  * Support  or  * Oppose  followed by a brief explanation, then sign your vote using "~~~~"

• Oppose for time being, although I agree the title is likely to be parochial. Unless I've misunderstood ICberg7's comments, I'm pretty sure a UK technician wouldn't refer to a socket as a jack, as in "a plug goes into a jack". However, I do know that what's described in the article isn't what's generally regarded as a "phone connector" in the UK; this term would be taken to mean those cuboid plastic blocks at the end of phone cabling used to plug into a wall or modem socket. I think UK technicians would describe the objects described in the article as "audio jacks". Apologies in advance if I've missed something obvious. Regards, David Kernow 02:05, 28 February 2006 (UTC)
• Weak oppose - These were originally telephone switchboard plugs, so probably move to Phone connector with no qualifier and use TRS and TS as sections within it. Telephone connector can be used for the other type, they can disambig link to each other and things like Phone jack will be disambig pages. — Omegatron 02:27, 28 February 2006 (UTC)
• Oppose - MOS states that articles should remain in thier initial english dialect, pressumablly that included the title. Also i'd like to see an aussie or similar weigh in this. Is jack plug a british peculiarity or is phone plug an american peculiarity? Plugwash 02:57, 28 February 2006 (UTC)
  • That does include the title, but it's only if the other options don't work:
    1. Does the article have an implicit connection with a certain dialect?
       • Not likely. The connectors were first used in telephone switchboards, which is where "phone plug" came from, and US switchboards predated UK switchboards by several years, but that's a tenuous connection.
    2. Is there a plausible dialect-neutral term?
       • I don't think this step has been exhausted yet.
    3. If these don't work, use the initial contributor's dialect
       • This is the step you're thinking of. — Omegatron 02:01, 1 March 2006 (UTC)
• Oppose WP:MOS#National varieties of English See also the Great Great Gasoline/Petrol debate and many more similar arguments--Philip Baird Shearer 12:37, 28 February 2006 (UTC)
• Oppose I never heard of "jack plug" until I encountered this article. I grew up calling them "phone plugs." But as long as "phone plug" is redirected here and mentioned up front, I'm happy. The proposed new title is not widely used and potentially confusing. --agr 13:36, 28 February 2006 (UTC)
• Support Read "More Discussion" section below ICberg7 05:00, 3 March 2006 (UTC)

Discussion

See The history of the article This fits WP:MOS#National varieties of English "If there's no strong tie, try to find synonyms that can be used in any dialect. If no such words can be agreed upon, the dialect of the first significant contributor (not a stub) should be used."

"In practice, a "plug" goes into a "jack." The (audio/visual) was added to the name to differentiate this connector from a standard telephone connector (RJ-11). The term "connector" was added to follow suit with other audio equipment pages" It was called a Jack Plug long before the RJ-11 was invented. --Philip Baird Shearer 12:47, 28 February 2006 (UTC)

A quick Google [Jack Plug] throws up many none UK web pages. Here are a couple for the first page of the seach of US edu sites which uses the term: http://www.wsu.edu/~brians/errors/jack.html http://www.ece.uiuc.edu/ecestores/jack.html So it is not just a UK expression. --Philip Baird Shearer 12:54, 28 February 2006 (UTC)

• Technically the wsu.edu page talks about the difference between the words jack and plug (the "list of errors" link at the bottom takes you to a page full of phrases that people word wrong or words that should be used in lieu of others). The phrase "jack plug" does not exist anywhere on the the ece.uiuc.edu page, although "phone plug" does. :-)ICberg7 05:15, 3 March 2006 (UTC)

Terms

Here's a list of the terms I can think of. Please add to it and annotate — Omegatron 02:08, 1 March 2006 (UTC)

• Jack plug
  • UK-specific — Omegatron
    • Are you sure its jack plug thats uk specific and not phone plug thats US specific?
  • Not used in the US.  :-) — Omegatron
• Phone plug
  • Derived from their original use in telephone switchboards — Omegatron
  • Modern use in audio is confusing with Telephone plug — Omegatron
  • Virtually never used (with this meaning) in the UK. Plugwash 02:34, 1 March 2006 (UTC)
• Quarter-inch plug
  • Only applies to one size, this article is about the whole series. Also using the size alone is ambiguous for some sizes (there is a 3.5mm Toslink variant and a 2.5mm DC plug). Plugwash 02:34, 1 March 2006 (UTC)
• TRS or TS connector
  • Also virtually unheared of in the UK. Plugwash 02:34, 1 March 2006 (UTC)
  • Used mainly to distinguish between two subtypes used in audio. There are other subtypes with more than three conductors. — Omegatron
• Audio connector
  • Not specific to this type
• Quarter-inch phone plug
  • this is the most unambiguous term I know
  • I also found this link http://www.switchcraft.com/products/jack-122.html which refers to them as '1/4" Phone Plugs' and cites U.S. military specification MIL-P-642(A)
  • for what its worth, I have a 1958 edition of the ARRL Handbook that uses the term "phone jack" for the 1/4" socket and "phono jack" for RCA connecter in the same article (p.513). Also note "TS" has a widely understood scatological meaning in the U.S. (tough s**t). --agr 02:51, 1 March 2006 (UTC)
  • Once again though this term only covers one subtype so is unsuitable for use as the main title of this article. Plugwash 12:42, 1 March 2006 (UTC)
• Tip-Ring Connector
  • Wikipedia doesn't need two articles on this subject; however, the original and best-practice technical name is "Tip-Ring Connector" (hyphen optional). This term is still used by telephone companies on both sides of the Atlantic, and a quick check shows that is used in both the US and UK when describing the component in a careful specification. The other terms are perfectly valid redirects. Robert A.West (Talk) 03:52, 1 March 2006 (UTC)
    • This is still a subset type of this connector, and unless someone writes a separate article, this leaves the tip-sleeve connector out in the cold.ICberg7 05:00, 3 March 2006 (UTC)
    • Maybe telcos still use the term, component suppliers and other users of the connectors certainly don't! Also Tip-Ring only convers one subtype. Plugwash 12:47, 1 March 2006 (UTC)

More discussion

I think that I was misunderstood when I requested the move. I proposed a new name of "Phone Jack (audio/visual)" and then went to describe why I think it should be called this, only after explaining that I thought the current title "Jack plug" was very vague. "(audio/visual)" was added to the article title for the express purpose of disambiguating the concept of an RJ-11 telephone connector.

As agr had said, I had never heard of the term "jack plug" until I came here. I had always called the connectors by their sizes and dispositions: 1/4 inch tip-sleeve, 1/4 inch tip-ring-sleeve, 1/8 inch headphone jack, and mini (could be applied to 1/8 or 1/16). The "Tip-Sleeve" and "Tip-Ring-sleeve" constitutes technical jargon that expands the concept of the "mono" and "stereo" (respectively) to encompass the full range of the uses of these connectors. The fact that these terms are unheard of in the UK doesn't surprise me, because most lay people don't just walk around calling it that. You start to use these terms when you've "been in the business" a while. They are only titles applied to the two major subsets of this connector (two-conductor and three-conductor). In fact, to make the page easier to understand, it might just be better to call them two-conductor and three-conductor and just stuff TS and TRS off on the side in parentheses.

Concerning Omegatron's link to switchcraft, while it doesn't say "tip" "sleeve" in regards to the name of the connector, it does say this about it's construction: "This series features one-piece tip rod and one-piece sleeve and plug body" Again, Tip-sleeve and tip-ring-sleeve are just titles applied to a particular type of "jack plug" to differentiate their uses. But that quote describes the two types using these terms.

Since this article contains information on more than a 1/4 inch connector, we obviously can not call it that, unless somebody wants to segment this article into each and every possible combination of connectors. (I know I sure don't want to do that)

According to the wikipedia article, Telephone exchange, the first telephone excange was opened in the US in Connecticut. And I quote: "Each cord has a three-wire TRS connector: tip and ring for testing, ringing and voice; and a sleeve wire for busy signals."

Now, regardless, TRS connector needs to be merged here for the sole fact that TRS is a form of the so called "jack plug." I just think that "jack plug" is something of a misnomer since any "plug" that plugs into any "jack" (think wall electrical outlet, telephone jack, ethernet jack, etc.) can be called a "jack plug" without someone thinking them in serious breach of bad terminology. Concerning the historical usage of this type of connector, I don't know why calling this article "Phone connector" (IMHO) would create a MOS issue. In all honesty, I didn't know what would be the best name to call this article (read above concerning various connector sizes) until I remembered the origin of the connector and its various uses. Saying "phone connector" will implicate the historical information as well as allow the article to continue to have information about all the various uses of the different size connectors.

Concerning the localization of the term "jack plug," I don't think this fits in the same category as the gasoline/petrol issue (i.e.: I'm not trying to change this article name because I'm a fat-headed American :-p). While "Petrol" is the norm in BE parlance and "Gasoline" is the norm in AE parlance, I as an American know that Brits call gas Petrol, and I would assume that at least some subset of Brits understand that we Americans call it gas(oline). I would consider the two terms interchangable (depending on my geograpic location) as I would lift/elevator, boot/trunk and others. Concerning "jack plug" though, I think this goes beyond who calls it where, but rather the fact that the term is ambigious.

In closing (yeah, I typed a lot...) I made the recommendation to perform a simple rename of this page, mainly for the fact that we can easily integrate TRS connector into this article, we can create a section for the TS-type connector (call it whatever you want), and at the same time lets us keep all the historical information that's already there as well as the stuff about the other-size connectors (such as headphone connectors).

I made this recommendation because I felt that it was the simplest, easiest approach to unifying this article

The above discussion is preserved as an archive of the debate. Please do not modify it. Subsequent comments should be made in a new section on this talk page. No further edits should be made to this section.

history of sizes

"The original 6.35 mm or 1/4" version, dates from 1878"

Shouldn't this be

"The original 1/4 inch (6.35 mm) version dates from 1878"

since the original plug was American? When did the world standardize on the metric size instead?

(Whoa. Since the international inch is now defined in terms of the millimeter (25.4 mm), 1/4 inch is exactly equal to 6.35 mm.) — Omegatron 19:28, 12 May 2006 (UTC)

Just how different were the canadian (now international), US and british inches anyway? Our inch article doesn't say! Plugwash 00:54, 14 May 2006 (UTC)

It should! — Omegatron 04:34, 14 May 2006 (UTC)

It says in the Imperial unit article: "the most precise measurement of the Imperial Standard Yard was 0.914398416 m " Tha corresponds to an inch of 24.399956 mm. The difference is well below the machining tolerance of the plugs. I added a link from the inch page. --agr 02:34, 30 May 2006 (UTC)

So that leaves the (pre-unification) US inch (which i suspect was the one originally used here.

6.35mm, 6.3mm, and 6.5mm jack plugs

I was about to edit the article on the assumption that "6.3" and "6.5" were just typos for "6.35" but then again I was not completely sure. Could someone clarify this ambiguity? -thanks, Onceler 21:42, 22 July 2006 (UTC)

I believe the first plug was American, and 1/4 inch, which is exactly 6.35 mm. See the section above this one. — Omegatron 22:12, 22 July 2006 (UTC)

And for better fittings, plugs are produced with minor slope in dimension toward 6.3 mm. That's right. In European Area, this will be selled out as "6.3mm Plug". Don't worry about, that's ok. But for the 3.5 mm or even 2.5mm Version please don't use Inch dimensions and don't try to make 1/8" and so on. This is completely wrong since they went defined by german standardisation organism first!! Cosy

Sleeve is ground on stereo jack?

It's not always the ground; sometimes the stereo uses differential signals (at least on my computer sound card). So what you are hearing is equivalent to the left/right signal subtracted by the sleeve signal. In other words, if you subtract the sleeve signal from the left or right signal, and then reference it to the ground, you will the the signal you're supposed to hear. You can confirm this by connecting your headphone/speaker sleeve to ground and connecting the ring and tip to the corresponding contacts on your source jack contact. You should hear noise. Now, take the sleeve signal and the left signal and put it through a differential amplifier. Connect the output of the differential amplifier to the headphone/speaker tip contact and ground the sleeve. You should now get the correct signal.

What sound card is that? — Omegatron 22:15, 6 December 2006 (UTC)

I'm using SoundBlaster Live. —The preceding unsigned comment was added by 211.72.233.5 (talk) 10:20, 12 December 2006 (UTC).

Sleeve is nominally the ground connection, but that doesn't nessacerally mean that it is tied to the PCs ground only that it is a common return and you can tie it to ground without breaking anything should you wish. Having an isolated ground for an audio output from an electrically noisy environment (the inside of a PC) is a pretty smart move. Plugwash 13:24, 12 December 2006 (UTC)

German Therm

The Therm for this Jack in German is "Klinkenstecker" (Stecker = jack). Congratulation for part usage where you are showing usage and dimensions for aviation (All aircraft wolrdwide are equipped that way in the pilot's cabin exept AIRBUS) —The preceding unsigned comment was added by 85.1.18.249 (talk) 00:30, 19 January 2007 (UTC).

aircraft-jacks

Perhaps not the best place to request some help, but i don't know of a better;-) I want to buy some of these aircraft-jacks and some fitting plugs, does anyone know the manufactorer and/or can post a correct keyword for further search at google?

best wishes,-- .rhavin 89.62.103.56 12:06, 12 March 2007 (UTC)

For those of us deaf in one ear...

For those of us deaf in one ear, could someone with the appropriate expertise please (as in, I am begging you) write a brief description of strategies or modifications we might employ to, e.g., headphones? I get fairly well annoyed by headphones where I can hear the piano, or I can hear the bass, but not both! For example, is it o.k. to cut off the stereo jack, and solder on a mono jack, and will that give me the correct mono signal to listen to? See Unilateral hearing loss. Perhaps the discussion of this issue would be better included there? Thanks! Bdushaw 10:15, 7 April 2007 (UTC)

You can't just solder on a mono jack since the amplifiers would then be loading each other. It might work in some situations but it's not a good solution and could cause distortion and theoretically ruin some amps (though most are probably protected against that sort of thing). You would really want to get a mixer of some type to mix the two channels together. If you're technically-minded, you could look at one of the many DIY headphone amp projects available online and modify one to be a mono mixer. It would be a pretty simple change.

That's not really relevant to this article, though — Omegatron 14:36, 7 April 2007 (UTC)

Humm...I was intrigued by the statement in the article "If a two-conductor plug of the same size is connected to a three-conductor socket, the result is that the ring (right channel) of the socket is grounded." Without knowing what I was doing, a few years ago I did this to one of the single ear headphones one gets on airplanes (the ones that clip on your ear) - that is, I cut off the one for the right ear only (I hear in that one), and soldered on a mono jack. This has seemed to work well for listening to movies on my laptop computer. I gather that what happened was that the laptop's amplifier was "smart" enough to detect that the right channel was grounded, a mono signal request was inferred, and it combined right and left channels for me - I was lucky this worked like this, you seem to suggest. (You aren't the first to suggest that all this should occur at the mixer level; it is also surprisingly difficult to find out about that as well, or perhaps it is too simple to warrant even a discussion...I use the alsa mixer on linux systems and so far I've been unable to figure out how to set mono output!) I did also once solder the right and left channels together on a headset, which behaved rather badly. Well, this line of thought might not be appropriate for this particular article, but I feel certain some discussion of these issues would be appreciated on the unilateral hearing loss page. I can try to start something there, but I don't really know how to best describe the technical details; I'll suggest that for the "To Do" list. Unilateral hearing loss is a not uncommon handicap. Bdushaw 18:23, 7 April 2007 (UTC)

Experimenting some more, I found that my single ear headphone was not working like I thought; I was getting very little bass (it is harder than you might think to sort this out, if you are like me!). But I also learned that monaural headsets (such as used for cell phones or VOIP on a computer) are a dime a dozen and provide an ideal solution for me, if they are designed to also listen to music. If I may be so bold, I will edit the article here to explicitly state that the sound from one channel is lost when a mono plug is put into a stereo socket - it states that one channel is grounded, true, but it seems useful to state that that half of the signal is therefore lost. Bdushaw 10:31, 9 April 2007 (UTC)

PC 99

Maybe the PC 99 standard should be mentioned somewhere? It specifies some color codes for the 3.5 mm jacks used in sound cards. --ZeroOne (talk | @) 19:47, 19 April 2007 (UTC)