Connecting some (probably ex-hifi) speakers to a PC

[rowdy]

I acquired some largish speakers very cheaply and would like to connect them to my PC via the headphone socket.

I know very little about audio equipment, perhaps someone can offer some suggestions

They are TEAC LS-83N speakers, depicted below with a QFR for size comparison.



They have spring-loaded terminals on the back.



What do I need to be able to connect these to the headphone socket on my computer?

Thanks

[fohat.digs]

50W means that they can handle 50 watts of power, but they probably need at least 5W-10W to drive them realistically to a reasonable level.

Something like this might be OK, but don't take my word, this is a 2-minute ebay search:

http://www.ebay.com/itm/2CH-Hi-Fi-Stereo-Amplifier-Booster-DVD-MP3-Speaker-for-Car-Motorcycle-Home-Mini-/111682262825?hash=item1a00c81729:g:xI8AAOSweW5VaBSM

and you may need something like this:

http://www.ebay.com/itm/Audio-Aux-5Ft-3-5mm-to-RCA-Male-to-Male-Stereo-Y-Cable-Adapter-for-MP3-iPod-etc-/181577265487?hash=item2a46d9314f:g:YCMAAOxyP4dTcid0

PS - they probably sound great - I "grew up" on solid state analog gear in the 1960s-70s-80s and it still sounds best to me!

[suicidal_orange]

What fohat said - you need an amplifier and a mini jack to RCA cable, as well as some wires from the amp to the speakers themselves.  The world of audio is much like keyboards so there's an amp for every budget and it's up to you how much you want to spend.

Also you don't want to connect it to the headphone socket unless you have to, a line out should get you a cleaner signal as it's designed to connect to an amplifier (many KOhm impedance) not some small speakers (generally around 30 Ohm)

[Coreda]

Yeah. You're going to need an amplifier to power those.

The red/black connections at the back use speaker wires (single/joined audio cables that split at the ends with bare wires). Those are then connected to the amp from which you can plug a standard 3.5mm jack audio to RCA adapter cable into from your headphone output.



I once had a setup which did this, using a Sony all-in-one system as the amp the speakers connected to it and the headphone jack output the signal to the stereo.

[rowdy]

Thanks guys   My problem is that I don't know what to search for.

I was hoping to get some nice bass from these - I prefer lots of bass

fohat: Thank you for the information and links.  I found the same amp listed on eBay Australia (different seller, but still from HK), and it costs more than the speakers )

Amp ordered!

I also have an embarrassing number of cables of different types, including one similar to the linked cable:

[Coreda]

I also have an embarrassing number of cables of different types, including one similar to the linked cable:

(Attachment Link)

That's the one. Plug the 3.5mm side into your computer's audio out and the RCA ends into the amp.

All you then need is speaker cables which are easily found and enough space to fit the speakers

[rowdy]

I also have an embarrassing number of cables of different types, including one similar to the linked cable:

(Attachment Link)

That's the one. Plug the 3.5mm side into your computer's audio out and the RCA ends into the amp.

All you then need is speaker cables which are easily found and enough space to fit the speakers

The speakers actually came with a couple of likely-looking cables in a bag taped to the back of one.

[RabRhee]

Most of the cheap amps that appear on eBay are 12v, designed to be used in a car. To use them in a house you will need a 12v power supply, probably at least 2 amps of power (that red amp says 2-4A max). Unless the amp you bought specifically comes with mains power, you will need one.

You may have one lying around, if you do, you just need to make sure it is 12v, more than 2 Amp, and that the centre pin is the +, as that amp. (although that last bit can be easily swapped if it is - centre)

if you don' t have one, something like this is needed - http://www.ebay.com.au/itm/DC-12V-2A-Power-Supply-Adapter-Charger-Transformer-Plug-FOR-CCTV-LED-STRIP-LIGHT-/191722087504?var=&hash=item2ca386e450:m:mHHIxYlOOQR2bU_4ts8eJdA

(sorry to add to the costs, its still probably the cheapest option for an amp. I have the exact same setup on a family PC)

[Hak Foo]

Also consider a thrift store for a used reciever.  Older stereo-only and non-HDMI stuff-- but not old enough to be vintage collectable-- are virtually worthless.  Sometimes you can get pretty nice ones-- decent makes, lots of inputs-- for a Jackson or less.

[rowdy]

Most of the cheap amps that appear on eBay are 12v, designed to be used in a car. To use them in a house you will need a 12v power supply, probably at least 2 amps of power (that red amp says 2-4A max). Unless the amp you bought specifically comes with mains power, you will need one.

You may have one lying around, if you do, you just need to make sure it is 12v, more than 2 Amp, and that the centre pin is the +, as that amp. (although that last bit can be easily swapped if it is - centre)

if you don' t have one, something like this is needed - http://www.ebay.com.au/itm/DC-12V-2A-Power-Supply-Adapter-Charger-Transformer-Plug-FOR-CCTV-LED-STRIP-LIGHT-/191722087504?var=&hash=item2ca386e450:m:mHHIxYlOOQR2bU_4ts8eJdA

(sorry to add to the costs, its still probably the cheapest option for an amp. I have the exact same setup on a family PC)

I have two boxes full of old power bricks.  I suppose I should look to see if I have one with the required output.

Also consider a thrift store for a used reciever.  Older stereo-only and non-HDMI stuff-- but not old enough to be vintage collectable-- are virtually worthless.  Sometimes you can get pretty nice ones-- decent makes, lots of inputs-- for a Jackson or less.

I had to look that one up - a Jackson would be about AUD$28.  The speakers were about 1/3 that price!

Unfortunately most of the thrift shops around here seem to have clothes and old toys only.  I have sent my other half on a mission, while she does her walks around the local streets, to find such a shop that sells keyboards.  No luck.

[rowdy]

I can has power!



Also this is the one I got: http://www.ebay.com.au/itm/291595190248

[RabRhee]

I can has power!

(Attachment Link)

Also this is the one I got: http://www.ebay.com.au/itm/291595190248

Yes, that should do the job, 3 amp so should be comfortably enough. + centre. Now you just have to hope that the connector fits the amp

Hak Foo is right about the used receiver or amp, if you can get one its likely to be better quality and more power, I like the car ones because they are small and you can hide them behind a PC case. But if size isn't an issue, long term a proper hi-fi amp will be better. These cheap car amps work fine enough though.

[Photekq]

Look into buying a second hand stereo amp from the 80s/90s, like a NAD or something. You can probably get a good one around $50-100. It'll make them sound a hell of a lot nicer than that cheap amp.

[rowdy]

Look into buying a second hand stereo amp from the 80s/90s, like a NAD or something. You can probably get a good one around $50-100. It'll make them sound a hell of a lot nicer than that cheap amp.

I don't even know if the speakers work yet!

[GuilleAcoustic]

Bass need a beefy power.supply stage on the amplifier with especially high capacity caps to store as much power as possible.

If you like Diy, the gainclone is a great and easy design that deliver around 60W, depending on the load impedance.

Feel free to ask any question, I'll try to answer them as clearly as possible.

[rowdy]

Bass need a beefy power.supply stage on the amplifier with especially high capacity caps to store as much power as possible.

If you like Diy, the gainclone is a great and easy design that deliver around 60W, depending on the load impedance.

Feel free to ask any question, I'll try to answer them as clearly as possible.

An interesting idea.  Been a while since I've built a kit anything.

The amp from HK is on its way (or soon will be), so I'll try that first, and at least find out if the speakers work.

[fohat.digs]

In my experience, working stereo receivers are very difficult to find in 2nd-hand stores, because they are snatched off the shelf the instant that they touch down.

When I do manage to find one on the cheap, I often nab it, because I love that old 1970s-1980s warm distorted sound, since that was what I heard during my peak music-listening years.

If you like the speakers, use the $10 one I linked and stay on the lookout for a good used receiver to drive the bass. With the pressure off, you can always find a good deal if you are patient enough.

[tronbeaver]

Look into buying a second hand stereo amp from the 80s/90s, like a NAD or something. You can probably get a good one around $50-100. It'll make them sound a hell of a lot nicer than that cheap amp.

I don't even know if the speakers work yet!

You might be able to have enough power to drive from a sound card to at least see if functional.

[rowdy]

In my experience, working stereo receivers are very difficult to find in 2nd-hand stores, because they are snatched off the shelf the instant that they touch down.

When I do manage to find one on the cheap, I often nab it, because I love that old 1970s-1980s warm distorted sound, since that was what I heard during my peak music-listening years.

If you like the speakers, use the $10 one I linked and stay on the lookout for a good used receiver to drive the bass. With the pressure off, you can always find a good deal if you are patient enough.

That's exactly my thought!  And to see whether the speakers actually work.

You might be able to have enough power to drive from a sound card to at least see if functional.

But despite my cable collection, nothing with a .5mm plug on one end and two pairs of bare wires on the other (at least not without sacrificing an existing cable).

[1swt2gs]

rowdy!

This is overkill for some computer speakers! 

[TacticalCoder]

What do I need to be able to connect these to the headphone socket on my computer?

Sweet!  That's the kind of setup I have in my living room to listen to music: a computer hooked to a good old Harman Kardon amplifier and stereo speakers.  That amp is more than 20 years old (and I'm using it since more twenty years: which is crazy, my amp is older than many GHer) or so and still doing its job just fine.  My speakers are KEF ones at the moment but I plan to change them soon.

So it's old-school style but for the "source": a computer playing mp3 and some flac/lossless music. TV is connected to the amplifier too.  I used to have a cassette player, a CD-player and then even a Mini-Disc player (the Sony MiniDisc thinggy, which never really took off) hooked to that amp

Now it's computer + DAC but the amp is still the same

My good old amp is not totally unlike this one:

[Badwrench]

I think you are going to be pretty good with that amp and those speakers.  The wattage of theamp gets you into what those speakers are rated, so the sound shold be quite good.  If you have a decent onboard eq, make sure to bypass on the amp.  If not, you can dial the highs and bass to a point with the amp.  That one is very similar to the lepai which I have had great luck with. 

[Snowdog993]

Well, the amplifier will work.  It should even though it is rated at 4w RMS per channel.  That's enough to drive the speakers. 
I won't go too far into detail, but you might need a better amplifier in the future.
Let us all know how it works out!

[fohat.digs]

Well, the amplifier will work.  It should even though it is rated at 4w RMS per channel.

Whoa!

The one I linked had much better specs than this, mine had 20W RMS per channel.

[Snowdog993]

Well, the amplifier will work.  It should even though it is rated at 4w RMS per channel.

Whoa!

The one I linked had much better specs than this, mine had 20W RMS per channel.

It is the same amplifier Fohat.  The MA-170.  The devil is in the details.

[fohat.digs]

The devil is in the details.

So I suppose that the ebay seller totally lied and listed the peak power as the RMS power in his description?

Probably to be expected.

[Snowdog993]

The devil is in the details.

So I suppose that the ebay seller totally lied and listed the peak power as the RMS power in his description?

Probably to be expected.

Yes.  That doesn't mean it's bad, it will work.  For the price, it's a good deal.  However, I believe Rowdy can find a second-hand amplifier or receiver rated at around 25-50w RMS that would be significantly better for a reasonable price.  For now, let's just see if it works.

[rowdy]

rowdy!

This is overkill for some computer speakers! 

It's the way to go

Well, the amplifier will work.  It should even though it is rated at 4w RMS per channel.  That's enough to drive the speakers. 
I won't go too far into detail, but you might need a better amplifier in the future.
Let us all know how it works out!

Oh.

The seller I got it from appears to have misrepresented it too.

I did look at the other search results, and for anything bigger the cost increased significantly.

At this stage I just want to find out whether the speakers work.  And I suspect the opportunities to crank for volume up will be few and far between.

[fohat.digs]

I think that this will turn out to be a decent little amp for basic use if you don't need to drive it too loud.

http://www.parts-express.com/kinter-ma-170-2-channel-mini-amplifier-bass-treble-rca-in-2x18w--310-372

Here is a nerd testing it pretty well and at about 15:00 proclaims that it produces about 5.7 strong clean watts:

https://www.youtube.com/watch?v=XPPrk-SULIs

[Snowdog993]

Oh.

The seller I got it from appears to have misrepresented it too.

I did look at the other search results, and for anything bigger the cost increased significantly.

At this stage I just want to find out whether the speakers work.  And I suspect the opportunities to crank for volume up will be few and far between.

Well, it's not necessarily "cranking it up" that is the problem.  It's the amount of headroom the amplifier has.  At higher volume the sound quality will substantially decrease.  And having around a 70db signal to noise ratio, it's not exactly "high end".

On the plus side, it will work good for what it is.

[fohat.digs]

And having around a 70db signal to noise ratio, it's not exactly "high end".

For ten frakking dollars, you can't ask for audiophile gear!

[Snowdog993]

And having around a 70db signal to noise ratio, it's not exactly "high end".

For ten frakking dollars, you can't ask for audiophile gear!

LOL!  It's good for what it is!  I'm not arguing that at all!  It will be enough to test the speakers.  If Rowdy decides, he can get a better amplifier in the future.  That's all I said.

[rowdy]

And having around a 70db signal to noise ratio, it's not exactly "high end".

For ten frakking dollars, you can't ask for audiophile gear!

What the speakers cost )

If they work, I can look at getting a better amp.

[fohat.digs]

Somewhat off-topic, but for people reading this and thinking (<$100) about hooking up turntables and vinyl to their sound cards:

http://www.phonopreamps.com/

these products are hard to beat at their price points.

[Snowdog993]

Somewhat off-topic, but for people reading this and thinking (<$100) about hooking up turntables and vinyl to their sound cards:

http://www.phonopreamps.com/

these products are hard to beat at their price points.

Actually, there is some pretty cool stuff there Fohat!  Nice find!

[rowdy]

That's a whole other money sick there!  Lucky I just want to see if these speakers work!

[fohat.digs]

there is some pretty cool stuff there

I have had a TC-750LC for several years and it works great. I upgraded the power supply from the fractional amp power brick that they gave me to a 2A Linksys left over from a dead modem and it helped a lot. But I had to buy a 3.5mm-to-1.3mm adapter because the TCC uses a small funny plug.

[fohat.digs]

Hey, Rowdy, just checking up on this.

Did it all work out?

[rowdy]

Finally the amp arrived.



Everything connected fine, plugged together well, and powered up as expected.

The amp has a light around the main dial on the front, which is the volume, and this light gradually changes colour.

The speakers both work!

Although due to lack of space they are a metre and a half behind me.  Listening to some familiar music it seems that I have cotton wool in my ears as the sound seems muffled.

The volume goes up reasonably well, but not as high as I'd expect, probably due to the amp.

So at least they work, which was the biggest question.  Now to decide whether I want to spend more money to get them to work better, if they even can.

I'm wondering whether the muffledness is because the speakers are behind me on the floor, rather than sitting on the desk in front of me.  Or because they are 1.5m behind me instead of 30cm in front of me.  Or because they have huge woofers whereas the little Logitech speakers don't.  Or because they are aged and inform, whereas the Logitech speakers are only a couple of years old (and the power button is already broken).

Any thoughts

Thanks for all the help so far

[Snowdog993]

Finally the amp arrived.

(Attachment Link)

Everything connected fine, plugged together well, and powered up as expected.

The amp has a light around the main dial on the front, which is the volume, and this light gradually changes colour.

The speakers both work!

Although due to lack of space they are a metre and a half behind me.  Listening to some familiar music it seems that I have cotton wool in my ears as the sound seems muffled.

The volume goes up reasonably well, but not as high as I'd expect, probably due to the amp.

So at least they work, which was the biggest question.  Now to decide whether I want to spend more money to get them to work better, if they even can.

I'm wondering whether the muffledness is because the speakers are behind me on the floor, rather than sitting on the desk in front of me.  Or because they are 1.5m behind me instead of 30cm in front of me.  Or because they have huge woofers whereas the little Logitech speakers don't.  Or because they are aged and inform, whereas the Logitech speakers are only a couple of years old (and the power button is already broken).

Any thoughts

Thanks for all the help so far

I will give you my thoughts.

First, check the connections inside the speaker itself.  Be sure all the speakers are properly connected and listen to each speaker in the cabinets and check if they are making sound at all.

I am guessing your midrange/tweeters are not functioning properly and if you play some music, double-check to see if there is any sound coming from them at all.  If there is little or no sound, they may need to be repaired because the surrounds are deteriorating.  That's normal.

It may even be happening with your woofers too.  Check and see if the edges of the speakers are solid.  They may be very worn out, and may need to be reconed or replaced.
Since they are not pushing/pulling properly, you will not get good sound at all.

The good news is you don't need to spend an arm and a leg to restore them.
A poor man's solution is using silicone on the surrounds.  You need a paintbrush and silicone.  It's not a great fix, but it may be something you can try.  You apply a thin layer and let it dry.

Hopefully, you will have speakers that work once again, but depending on the damage, they may not work at all.  The voice coils may be burned out.  If this is the case, you will need to replace the speaker components themselves.

If you find that to be too costly, you might want to look into a new pair of speakers.





Edit: Here is a good example of a midrange and tweeter that could be repaired using the silicone method.  I really should just replace them on both speakers.  We will see how they turn out.

[fohat.digs]

Listening to some familiar music it seems that I have cotton wool in my ears as the sound seems muffled.

That is troubling. Regardless of the details of placement or room acoustics, the speakers need to be producing the proper sounds.

Like snowdog said, first verify that the speakers are not physically damaged and put your ear up to them, one at a time, and try to determine whether all are functioning properly, if at all.

Best is to test each type appropriately, for example try a flute solo in the tweeters or a bass solo on the woofers.

Of course, the first thing to check is wiring and plugs, then look at playback settings to make sure that everything is balanced neutral and that bass or treble (or other equalization, if available) are not turned out to extremes.

[Spopepro]

Correct advice so far. Check those things.

More stuff to check:
Easy first: are the cabinets a ported bass design? Is the port rear-firing and you have it up against the wall? Some speakers need space behind them because of ports.

Harder: crossovers often require big capacitors, and big capacitors can be expensive. But not if you use electrolytic caps... which have a very finite lifespan. If these are old, you might have a poorly functioning crossover. To find out, you would have to disassemble the speaker, so I'd call this the last thing to try.

[Snowdog993]

Correct advice so far. Check those things.

More stuff to check:
Easy first: are the cabinets a ported bass design? Is the port rear-firing and you have it up against the wall? Some speakers need space behind them because of ports.

Harder: crossovers often require big capacitors, and big capacitors can be expensive. But not if you use electrolytic caps... which have a very finite lifespan. If these are old, you might have a poorly functioning crossover. To find out, you would have to disassemble the speaker, so I'd call this the last thing to try.

Yeah crossovers can be the life or death of a speaker system.  It is a last resort.  Those speakers are not the highest quality, and if you decide to do the crossover thing, you might want to consider replacing all the components if you go that route. 

However, if you do, you might wind up with a kick ass speaker system! 

[fohat.digs]

However, if you do, you might wind up with a kick ass speaker system! 

Yeah, with China / internet / ebay / etc components such as speakers have become easily available and cheap nowadays.

I built a subwoofer in the late 1980s and the driver alone was over $100, and it was not even a "top name brand"

note to self: I still have it, I really need to build a new cabinet for it (huge 15" with massive magnet and dual voice coils .... )

[Snowdog993]

However, if you do, you might wind up with a kick ass speaker system! 

Yeah, with China / internet / ebay / etc components such as speakers have become easily available and cheap nowadays.

I built a subwoofer in the late 1980s and the driver alone was over $100, and it was not even a "top name brand"

note to self: I still have it, I really need to build a new cabinet for it (huge 15" with massive magnet and dual voice coils .... )

Hehehe!  I know the feeling.  I went overboard on my A/V system.  It wound up costing me more than I wanted, but it turned out nice!

[rowdy]

Thanks guys - a list of things to try.  Both woofers are working, the tweeters I'm not so sure about, although there was a little sound.  Trying different music/sound samples is an excellent idea.

Easy first: are the cabinets a ported bass design? Is the port rear-firing and you have it up against the wall? Some speakers need space behind them because of ports.

Excuse my ignorance - ported bass design means it has a hole in the back of the speaker?

These have no holes - the back is just a sheet of wood with the spring connectors for the wires in the middle.

[fohat.digs]

ported bass design means it has a hole in the back of the speaker?

There *may* be a hole somewhere - sound waves bounce around inside and this gives them a way out. It means that the cabinet can be smaller and provides more efficiency. That is an entire realm of esoterica that you may not need.

Look for a hole of some decent size but probably not big enough to get your hand in, and ensure that it is not blocked. Low frequencies are not directional like high frequencies are.

 

[rowdy]

No holes on the back, top or sides.  Unless there's one underneath, which is unlikely as they sit flush on the floor, I'd say they are probably not ported.

Weekend job, I don't have enough time to do things like this during the week.

[Snowdog993]

No holes on the back, top or sides.  Unless there's one underneath, which is unlikely as they sit flush on the floor, I'd say they are probably not ported.

Weekend job, I don't have enough time to do things like this during the week.

No big deal at all.  I have the feeling if there is a tuned port at all, it would be in the front.  You will still have to remove the speakers to check the wiring as well.

Essentially, there are a few types of loudspeakers, acoustic (air) suspension and bass reflex.  Air suspension has no holes at all in the cabinet, and are less efficient than bass reflex, because the port allows the speaker to "breathe" and give more bass response.

You are right about it being a weekend project.  If you have to use silicone to repair the speakers, that alone takes 24 hours to allow the silicone to harden before you can test them again.  Hopefully that will be all that is needed to be done.

The fabric cover on the front of the speakers should be easy to remove and replace.  There are usually pegs in the corners to hold it in place.  Makes it easy to clean as well.

[rowdy]

I opened one of the speakers.

It has some fluffy stuff glues to the inside of the back panel.  The green wire has a capacitor, the other wires do not.



All wires are plugged in.



The woofers don't look as big from the back )



They are ported - the hole is in the front.



They look fairly simple inside.  Probably something simple has gone wrong, like the coils or cones need replacing.