help with 3.5mm connection

[jtay]

sorry if this isn't the right forum, but couldn't post in technical or hardware. I've bought a couple of harman kardon onyx 3s and want to be able to use them, occasionally, in a wired stereo set up. Though bluetooth, they also have a 3.5mm stereo socket. I'll be splitting the audio from the source - mp3 player - and sending a mono signal to each of the two speakers. However, I want to ensure that the signal delivered, though mono, is played through both of channels for each speaker ie left speaker receives mono left channel but plays through both of its left and right channels.

I've been trying to find a 3.5mm adapter - or some other solution to achieve this end. I'm not sure if an adapter which delivers a mono signal to a stereo socket, without more, will merely play through one channel of the speaker or could create some problem.

could anyone guide me to the solution and product for this sort of setup. I'm looking low budget. Most likely use will be a setup useable outdoors in summer.

thanks

Chris

[Rothchild]

Not sure I've completely got my head around which sockets are on what but it sounds like you need a TRS (Tip, Ring, Sleeve) plug, to go in the mp3 player

http://www.head-fi.org/image/id/5369922

and a pair of TS plugs for the speaker ends


Ok, as I read again I see what you're asking. You'll need TRS plugs to go in the Onyx's but for each on you just need to short the tip and the ring, this will put the same signal on both the L&R inputs of each onyx. Obviously the left feed is shorted with the left signal and visa versa for the right.

[Mark Grant]

I you plug a mono jack into a stereo input on the speakers then the right signal will be shorted to ground so wont do anything.

some pinouts, the ring is right on 3.5mm TRS which is shorted to ground with a mono TR plug/socket.
http://pinoutguide.com/Home/Tele35s_pinout.shtml

The best bet might be to use a 3.5mm stereo Y lead and then two 3.5mm stereo cables so that both speakers receive the left and right.
https://www.startech.com/uk/Cables/Audio-Video/Audio-Cables/Slim-Stereo-Splitter-Cable-35mm-Male-to-2x-35mm-Female~MUY1MFFS
and two leads:
https://www.startech.com/uk/Cables/Audio-Video/Audio-Cables/6foot-Slim-35mm-Stereo-Audio-Cable-Male-to-Male~MU6MMS

[jtay]

thanks for the replies. So, I need a couple of TRS adapters with the T and R shorted? Are there any ready made adapters like this, or even cables with such a plug at one end? Links to UK retailer would be a help.

Mark, if I understand you, think you're presuming there are 2 audios in on each speaker, whereas there's only a single 3.5mm input socket per speaker.

[jtay]

found this on amazon:

https://www.amazon.co.uk/C2G-3-5mm-Stereo-Female-Adapter/dp/B002DWAXKU/ref=sr_1_37?ie=UTF8&qid=1482110404&sr=8-37&keywords=mono+3.5mm+adapterC2G 3.5mm Mono Male to 3.5mm Stereo Female Adapter

Will this do the trick on the end of a regular 3.5mm stereo cable (which will go to a splitter on my MP3 source)? I'm still unclear whether this is the same, in practice, as a TRS plug shorted between tip and ring. Will the Amazon adapter ensure a mono signal from one channel of my source plays out of both left and right channels on a single Onyx speaker?

Though I'm not doing a sophisticated set up, I don't like so many connections along the way. Ideally, I'd prefer to use a single 'cable' - with a stereo 3.5 male which simply splits into two, and each split cable ends with the appropriate mono 3.5mm. Don't suppose this readily exists? Unable to find so far.

[RothwellAudio]

I looked-up the specs for those speakers but ended up confused. Am I right in thinking each speaker has a stereo input socket? If so, why? Which of the pins are used? You need to find that out first. Then I would wire-up a custom lead to avoid adaptors because there's rarely an adaptor which will do the job and even if there is they're usually unreliable.

[jtay]

Rothwellaudio - the speakers are simply bluetooth speakers, so their billed method of connection is bluetooth, not via a cabled link. Like many bluetooth speakers these days though, they've also got a socket for a bog standard 3.5mm stereo plug. Think you're seeing them more as regular passive stereo speakers with querky audio input. As a bit more background, they will stand as individual speakers delivering stereo output, and Harman Kardon have also built in the ability for two speakers to link together by bluetooth for 'dual mono' sound, not true stereo. So, that form of link does not provide the benefits of stereo imaging etc. Because of this, as I'm buying a pack of 2, thought it would be nice to try them as a proper stereo pair by splitting left and right channels as per normal and ensuring that each speaker doesn't only operate as half a speaker (by ensuring that the mono audio received is sent to both channels of the individual speaker). As both speakers are carryable, battery fed, it would make for a fairly flexible solution I could use outdoors or away from home, UK weather permitting. The speakers get reasonable write ups in their own right, so I'm wondering if doubling up and fed a better than bluetooth signal, would 'up the ante' and get more out of them. It's all a bit of fun and experimentation on my part :) I'll also, out of curiousity, see what they sound like fed a better audio signal from a decent dac, but all this is only possible once I've resolved the cabling. :scratch:

[RothwellAudio]

Rothwellaudio - the speakers are simply bluetooth speakers, so their billed method of connection is bluetooth, not via a cabled link. Like many bluetooth speakers these days though, they've also got a socket for a bog standard 3.5mm stereo plug. Think you're seeing them more as regular passive stereo speakers with querky audio input. As a bit more background, they will stand as individual speakers delivering stereo output, and Harman Kardon have also built in the ability for two speakers to link together by bluetooth for 'dual mono' sound, not true stereo. So, that form of link does not provide the benefits of stereo imaging etc. Because of this, as I'm buying a pack of 2, thought it would be nice to try them as a proper stereo pair by splitting left and right channels as per normal and ensuring that each speaker doesn't only operate as half a speaker (by ensuring that the mono audio received is sent to both channels of the individual speaker). As both speakers are carryable, battery fed, it would make for a fairly flexible solution I could use outdoors or away from home, UK weather permitting. The speakers get reasonable write ups in their own right, so I'm wondering if doubling up and fed a better than bluetooth signal, would 'up the ante' and get more out of them. It's all a bit of fun and experimentation on my part :) I'll also, out of curiousity, see what they sound like fed a better audio signal from a decent dac, but all this is only possible once I've resolved the cabling. :scratch:

I'm still confused. I wasn't seeing them as passive speakers, I was seeing them as active speakers - but a pair of speakers, each one individually mono. So that's not correct? Are these things sold as just one unit? And each unit has one speaker in it and plays in mono? And if you feed it a stereo signal (hence the stereo socket) it will sum them to mono?
If that's the case, and you have bought two of them, you need to feed one speaker from the left channel of your source and the other speaker from the right channel of your source. Your source has its outputs on the tip and ring of its 3.5mm socket. That bit is straightforward. Each HK Onyx may need to be fed a signal on both the tip and ring of its input socket, or may be happy with a signal on just the tip with the ring open circuit, or may even be happy with the signal on the tip and the ring shorted to ground - but I doubt that last option will work.
Five minutes playing around should answer those questions. Then you need to wire up a custom lead to suit.

[Rothchild]

The speakers are stereo and have a stereo input, but OP wants to use a pair of these stereo devices, so requires that each device only receives one channel. therefore they need a stereo (trs) for the mp3 player and a further 2 TRS plugs (one for each speaker system) which have the tip and the ring 'duplicated' (ie one has both to be L channel and the other has both set to R channel).

I'm not sure you'll be able to buy one of these leads but it shouldn't be too hard to make up one.

[Rothchild]

Side note, it might help to consider that 'Stereo' is a recording / playback technique, not strictly a type of plug / source etc. It might be simpler to talk in terms of 1 or 2 channels.

What you have is a 2 channel source and two 2 channel playback devices, however, you want to feed each of these devices only one channel (L or R) so you take a 2 channel plug (TRS) and put the L channel on both signal parts of the plug (the tip and the ring) and the R channel on the other one. Plug them in to the 2 channel input of each device and away you go, both 'sides' of the device are now playing the same thing.

[RothwellAudio]

The speakers are stereo and have a stereo input...

Yikes - can't be a very wide soundstage :lol:
Anyway, that's cleared up my confusion and your explanation of what's required is spot-on.
Yes, I agree that making up a custom lead will be better/easier than finding an adaptor.

[jtay]

I'm still confused. I wasn't seeing them as passive speakers, I was seeing them as active speakers - but a pair of speakers, each one individually mono. So that's not correct? Are these things sold as just one unit? And each unit has one speaker in it and plays in mono? And if you feed it a stereo signal (hence the stereo socket) it will sum them to mono?
If that's the case, and you have bought two of them, you need to feed one speaker from the left channel of your source and the other speaker from the right channel of your source. Your source has its outputs on the tip and ring of its 3.5mm socket. That bit is straightforward. Each HK Onyx may need to be fed a signal on both the tip and ring of its input socket, or may be happy with a signal on just the tip with the ring open circuit, or may even be happy with the signal on the tip and the ring shorted to ground - but I doubt that last option will work.
Five minutes playing around should answer those questions. Then you need to wire up a custom lead to suit.

I've double checked just to confirm I've got it right (always stand to be corrected): Each 'unit' has a number of drivers and delivers stereo sound in theory, if not that effective in practice. Otherwise, then absolutely as you say, I'd just feed left channel to one and right to the other. I just want to avoid that loss of use/power from redundant drivers. If I've got it right, pic should be attached of speaker with grill removed showing stereo driver configuration

18882

[jtay]

When the speakers arrive I'll try some things out and have a go at the home made cable suggested. Your comments and advice appreciated

Chris