replacing ghetto sound system?

[slybunda]

hey all looking to put a cleaner sound solution in my cab. the existing one works but seems dangerous to me since the transformer i put a red box around in the pics runs a bit on the hot side.
iv been recommended a Wangma WM-333 : https://www.ebay.co.uk/itm/112818862850
since i want to keep this cheapo is that all good for me? i got 2 speakers which are 5w and 4ohm each.
thanks.

[slybunda]

Everyone using headphones i guess..

[lilshawn]

Everyone using headphones i guess..

no, just not everyone peruses the jukebox forum on a forum dedicated to arcade stuff. it's a bit nice here.

that amp is not a bad amp... i've seen a couple others (basically all clones of each other anyway) and the performance is quite good. as long as you are happy with the performance of the speakers themselves, (looks like some old computer desktop speakers) its a good self contained solution.

i wouldn't be worried about the transformer getting hot. it's a fairly inefficient way to produce power, so it tends to generate a bit of heat as waste power when it's being operated. as long as it's somewhere people aren't going to be coming in contact with it, (i hope not anyway) i wouldn't consider it an issue.

with the power amp, you may have to supply your own power supply, as your computers power supply (depending on it's performance) may not properly supply power to the amp and its highly variable load. Computers kind of expect the load to stay pretty constant and don't do well with variations... especially on the 12v line which is converted and used by most computers these days to power the main core voltage for the CPU chip. high variances in the +12v supply voltage could cause the computer to crash. playing music is going to make the load on the 12 volt go up and down a lot, especially at higher volumes.

a power brick of 12v and about 2 Amps (2000mA) would suffice and are quite popular.

[slybunda]

apologies i saw this sub forum to be Audio so i thought it was best to post here. if a mod can move the thread to the arcade section that would be great.

@lilshawn transformer is out of the way but its powered on all the time which is what i dont like. self contained amplifier would be good since i can run it from the pc power supply thats in the cab and has 12v available. just dont want to get something thats gonna burn out after a few months use.

[Zebidee]

@lilshawn transformer is out of the way but its powered on all the time which is what i dont like. self contained amplifier would be good since i can run it from the pc power supply thats in the cab and has 12v available. just dont want to get something thats gonna burn out after a few months use.

I suggest you look into using either a relay or a smartstrip to control power to the rest of the cab, depending on whether the PC is on or off.

[slybunda]

I will probably just get that wm-333 amplifier i linked in first post. Just hope its not worse than the current solution lol

[lilshawn]

it's usually a good idea to use a relay of some sort to power off unnecessary items.
I normally have lots of 12v relays around and just use the computer power supply to switch them on when the power goes on. ready made items like smart strips that zeb mentioned let you plug the computer into an always powered "control" outlet and all the other stuff into "switched" outlets so when the strip detects the computer going on, it turns on all the other outlets. that way nothing unnecessary is powered while it's "off"

you can go ahead and use the aforementioned amp, it's a great little unit, but just be clear i still recommend to use an external power brick to power it, as the variable load of the amp on the computer power supply while it's in operation can play havoc on the computer causing it to crash.

lights stuff are fine to power with the 12v computer supply, since the load very rarely changes... but amplifiers vary the amount of power they need based on what's currently playing to actually drive the speaker. so if you play a song that's like a "wump wump wump wump" bass drum line, the load on the computer supply goes up and down and up and down and up and down every time the bass drum hits. computers do not like having a power rail do this. especially the 12v line since it's used to supply core voltage to the main CPU. too much load makes the voltage dip down...too far down, and the computer will crash.

it might not be a problem, since it appears you only have a couple small speakers, and you might not play it very loud... but it's something to be aware of if you choose to just power it from the computer supply.

[slybunda]

Ok thanks for the reply. I will first try it from pc power supply. If i get issues then can always get a separate brick.

Anyone had any experience with the wm-333 amp?

[lilshawn]

ive used a pile of these random china amps... most of those Chinese amps use a Philips/ Toshiba TDA1558 or TDA1514 or TDA2005 or other TDA flavor amp IC. they are pretty much clones of each other and all the amp IC's themselves are all basically the same and overall pretty good and efficient and need a minimal amount of supporting parts to work, so it keeps the bill of materials low...thats why they can be sold for like 15 bucks each and they still turn a profit.

they all go by the weird Chinese names like Lepai or Kinter or Teli and so on, with random numbers for models that tell nothing of what it's capabilities are...(most other amps would be like a "BT245" for a bluetooth capable 2 channel 45 watt amp kind of naming convention) but these amps, the makers usually smack the number pad with their forehead to create them... but chances are pretty good any other 22watt mini amp is going to be exactly the same inside as the next 22 watt mini amp with the same amp IC chip and controls... just a different color case and name.

the IC chips themselves are pretty good. Toshiba/Phillips been making them for a number of years now and use them in everything from cd players and radios to TV's, computer speakers and bluetooth speakers. they have a number of protections to keep users from blowing them up if you short the outputs and whatnot, so they are pretty tough to kill unless you really do something stupid.

overall i'd give china amps a 7/10, good bang for your buck, but don't expect to drive some monster floor speakers with them. they have their place and do small installations like these well.

[slybunda]

Excellent. Will give the cheapo amp a try and see how i goes

[Zebidee]

Whatever you do, get the 12v brick, for the audio, before you get the issues. Don't run it from PC PSU, that is recipe for sadness as lilshawn has outlined above.

[slybunda]

If i was to spend more cash for a higher quality amp what would you guys recommend that also has a small footprint?

[eds1275]

I can't imagine a good sound system doing much for an arcade machine, considering the sound generally wasn't all that good in the first place. For authenticity, cake the speakers in beer and cigarette smoke and flashback to the 80's!

Seriously though I hope you are satisfied with the new amplifier and it puts your heat fears to rest.

[lilshawn]

If i was to spend more cash for a higher quality amp what would you guys recommend that also has a small footprint?

"quality" in these cases really doesn't matter, as about 99% of all small amps use the same amp IC chip. so "quality" is going to be the same across the board. Where things REALLY matter is the speakers, the cabinets, the crossovers... all of these things are going to determine if it sounds like trash or not. i can drive a 600 set of bose speakers with a 15 buck china amp and it sounds not bad at all. granted, at high volumes it distorts a bit and starts to get a little freaky, but for 20 watts, what are we expecting?

for all intents and purposes, speakers just randomly built into a cabinet aren't going to perform great. people have spent lifetimes writing dissertations on sound design, so i'm not going to go into it here... but TBH, installing an already built speaker system is going to be your best bet. grab yourself a set of decent logitech z series speakers, cut a big hole and throw some fabric over them and let 'er buck. all the design work has been done for you.

if you insist though, the Lepai LP1601S is a pretty good upgrade from the cheapie china amps and it sells for 99 bucks most places... It says it's a "200 watt Class D amplifier"... the manual itself states the amp is capable of 160x2 (at 10% THD)... so take anything you read these days with a tablespoon of salt.

[slybunda]

Not bought anything yet. Was hoping to get something with decent build quality so it doesnt blow up or overheat

[slybunda]

Well finally getting around to sort this out, iv got a few amplifier boards on order. An XH-A232 and a XH-M543. Combined total of £7.50p which is around $9 all in delivered.
Will test these out and see which one i go with. After realising my Bluetooth speaker is only 3w i guess i dont need mega power to go super loud.
May look into some front mount speakers for the cab at some point too.

[RandyT]

Well finally getting around to sort this out, iv got a few amplifier boards on order. An XH-A232 and a XH-M543. Combined total of £7.50p which is around $9 all in delivered.
Will test these out and see which one i go with. After realising my Bluetooth speaker is only 3w i guess i dont need mega power to go super loud.
May look into some front mount speakers for the cab at some point too.

If you aren't looking to go super loud, or drive large speakers, 12v is usually fine for those.  But those Class D amps really like to get more than that.  If you find you are getting distortion at higher volumes and it's not from over-driving the speakers, give the amp some more voltage.

[Zebidee]

Well finally getting around to sort this out, iv got a few amplifier boards on order. An XH-A232 and a XH-M543. Combined total of £7.50p which is around $9 all in delivered.
Will test these out and see which one i go with. After realising my Bluetooth speaker is only 3w i guess i dont need mega power to go super loud.
May look into some front mount speakers for the cab at some point too.

Assuming you want to get some better speakers to match your amp, you may want to add a Zobel network termination to your speakers.

That sounds fancy, but is really just a capacitor and resistor across the + and - terminals. This balances out the load on your speakers created by different frequencies.

Speakers might be nominally "8 ohms" or whatever, but in reality part of that is inductance, not just resistance. When you have high frequencies, the inductor will resist more, thus the total impedance goes up, and vice-versa. Makes life hard for your amp, your speakers and your ears.

The Zobel network or termination automatically balances that variable impedance so that it remains more constant (the capacitor passes high frequencies easily but blocks low frequencies, the opposite to the inductor inside your speaker).

In a practical sense, this means you can both drive your speakers a little harder while getting better quality music.

Here is an interesting video that explains it maybe better than me:



There are maths formulas and even calculators out there to work out the ideal values, but mostly it comes down to roughly a 0.1uF (104) capacitor and a resistor (4.7R to 10R typical starting point, suggest rated for 2W+, but really it depends on your amp).

The cap value seems pretty consistent, and it is OK to experiment with some different resistor values, listen and use what works best.

Here is an example of my recent implementation:

http://forum.arcadecontrols.com/index.php/topic,166352.msg1756157.html#msg1756157

[RandyT]

The Zobel network or termination automatically balances that variable impedance so that it remains more constant (the capacitor passes high frequencies easily but blocks low frequencies, the opposite to the inductor inside your speaker).

This is interesting, but I'm having some trouble truly understanding the net effect the circuit has on the sound output.  It sounds like it's little more than a filter, which helps to negate the drivers natural tendency to favor low frequencies.  If so, how does this differ from say, just bumping up the treble a bit or lowering the bass, at least on amps where this is an option?
   
Also, since many amplifiers can easily handle a range of impedances, I'm not sure how this would particularly make the amplifier any "happier" assuming this variation of impedance is already taken into consideration for the amplifiers speaker ratings.

[Zebidee]

This is interesting

Thanks

I'm having some trouble truly understanding the net effect the circuit has on the sound output.

Watch the video, or find your own independent sources (google it, or whatever works).

The point is to keep impedance constant - within the range your speakers (and amp) are designed to operate. This is especially important for high frequencies that can make your speaker impedance spike. This causes stress to your amps, speakers and ears.

It sounds like it's little more than a filter, which helps to negate the drivers natural tendency to favor low frequencies.

While is does utilise RC frequency filtering characteristics, it is not a filter as such. It is a balancer, you aren't losing anything. It prevents your speakers from being driven too hard, especially by high frequencies, but it works both ways.

It does work better for bass or low-mid range speakers, but balanced properly it works to improve output for anything even a tweeter.

If you are including all these different speaker elements then you should just dive into the rabbit hole and start looking at crossover networks.

If so, how does this differ from say, just bumping up the treble a bit or lowering the bass, at least on amps where this is an option?

A lot, and a lot is to be gained. You can add Zobels to your speakers (or amp outputs, if they don't already have them) to get benefits, while retaining your bass/treble controls.

Also, since many amplifiers can easily handle a range of impedances, I'm not sure how this would particularly make the amplifier any "happier" assuming this variation of impedance is already taken into consideration for the amplifiers speaker ratings.

Consistency, my friend    Less peaks and drops from the speakers, keeps the amp output more constant, It all makes the sound better.

[slybunda]

I do have an unused universal laptop power supply thats been sitting around for over 10 years. Its 120w and had a output rating of various voltages but highest was 24v and a little over 5 amps. Would that suffice?

Also i do have a subwoofer attached to the subwoofer/center speaker output of the motherboard so sound is very nice and overall loudness is good.

Anyone able to work out what sort of power the existing amplifier makes thats pictured in my first post?

[Zebidee]

I do have an unused universal laptop power supply thats been sitting around for over 10 years. Its 120w and had a output rating of various voltages but highest was 24v and a little over 5 amps. Would that suffice?

Should be sufficient. You can probably google the specs.

[slybunda]

How much power do you guys run in your cabs?

[Zebidee]

I've got a 24v 200W 10A PSU for my ZX-502MT amp with 2x50W speakers, but iirc the specs say 3A is plenty. So that laptop PSU should be sufficient for you.

Even with the Zobels installed, I can't really go above "6" on the volume dial before the speakers are starting to be overdriven. Which is good, a mid-point. Without the Zobels, I can only get to "4" and the tweeters are sounding squeaky/tinny.

Zobel terminations for your speakers are super-cheap and easy to install, and easy to tweak by a bit of knouse and by ear, without having to understand all the maths.

If you have a woofer (and you are keen), you can think about crossover networks which work on a similar principle. They direct your low frequencies to the woofer, and the higher frequencies to your mid-range and/or tweeters.

In my experience, most people building or restoring arcades don't care much, arcade music is mostly just unsophisticated blips and bloops anyway, and they play their music on something else (like a hifi system).

But... if you want to actually play music from your arcade, which some people (like me) do for various good reasons, then these details are worth looking at.

[slybunda]

I thought the pc motherboard had built in crossover since its got dedicated center and sub out?

[Zebidee]

I thought the pc motherboard had built in crossover since its got dedicated center and sub out?

There would hopefully be some sort of crossover and maybe a zobel built into the PC audio output, and even more hopefully into the amp, but the manufacturers' can't tailor it to your amp or speakers (because they don't know what they will be). Even the length of speaker cable makes a difference. In any case, it is best to have zobels placed at your amp output (by manufacturer preferably) as well as "termination" at speakers.

[RandyT]

Honestly, there's no need for the PC hardware to have any of that.  It can all be handled in the digital domain through the DSP (Digital Signal Processing) chip.  If you've ever wondered how they manage to make music being played on a cell phone not sound completely god-awful, it's due to this type of processing.  Most small BT speaker systems use it as well, due to the tiny drivers they use. 

The Zobels sound like they are a form of compression.  I once had a dedicated piece of audio equipment called a "compander", which did similar evening out of frequencies.  It did make some things sound better, but it did so at a cost.  Radio stations used to compress the heck out of their transmissions (maybe they still do), which generally made them sound better on the typical equipment used to listen to them.  But you could hear what was lost when listening directly to the source material. I plan to try them at some point with a switch in-between to see what effect they really have on the sound.  Probably not a bad idea to try it this way before committing to it fully.  It's obviously not for everyone, because I've yet to see such a simple circuit included by default from a speaker manufacturer, although I admit that have run across it once when disassembling something with a speaker in it.  I had no idea why it was there, but I guess I do now .

[Xiaou2]

I've got a 24v 200W 10A PSU for my ZX-502MT amp with 2x50W speakers, but iirc the specs say 3A is plenty. So that laptop PSU should be sufficient for you.

Even with the Zobels installed, I can't really go above "6" on the volume dial before the speakers are starting to be overdriven. Which is good, a mid-point. Without the Zobels, I can only get to "4" and the tweeters are sounding squeaky/tinny.

Zobel terminations for your speakers are super-cheap and easy to install, and easy to tweak by a bit of knouse and by ear, without having to understand all the maths.

If you have a woofer (and you are keen), you can think about crossover networks which work on a similar principle. They direct your low frequencies to the woofer, and the higher frequencies to your mid-range and/or tweeters.

In my experience, most people building or restoring arcades don't care much, arcade music is mostly just unsophisticated blips and bloops anyway, and they play their music on something else (like a hifi system).

But... if you want to actually play music from your arcade, which some people (like me) do for various good reasons, then these details are worth looking at.

 This is Utter Nonsense.

 If your tweeters start to sound "Harsh",  that is due to their design.   That is the difference between something
like a generic Horn tweeter,  and an Audiophile grade tweeter.  Many Audiophile drivers, are designed not to
produce that "Harsh" level of effect.

 However, in certain instances, Audiophiles use Tube amps, to help "Smoothen" that harsh sound output.

 Ive heard this very difference, across the many different speakers that Ive owned (probably at least 30 different
brands.. as Im a speaker-holic).   My buddies dual 15" woofer Cerwin Vegas... that use horn tweeters, go
LOUD AF... but... they are so Harsh to the ears... especially at high volume levels... that you really would not
enjoy long term listening sessions with them.   They are, in fact... just a "Party"  speaker... made to be able to
blast music loud enough, to overcome large rooms of loud people taking / dancing.

 My  EPI 100v  speakers, are completely different.  No harshness in the highs and mids, unless you are listening
to some of the Worst recordings.  And even then, a touch of EQ, and things tend to be just fine.

 Even my non audiophile Techniques 12" 3 ways... were not Harsh in the Highs / Mids.   But I DO in fact have
other speakers, that are very Harsh in the highs and mids.   Again... this is due to the difference in drivers.
Not crossovers.  Not Filters.  Not EQ.  The actual driver design,  itself.

 In fact... the EPI only has a single Cap, to prevent bass from going to the tweeters... where as the woofers are designed
to use a specific voice coil wire gauge, and number of windings...etc... to automatically filter out any highs from reaching
the woofers.


 So... The tweeters themselves, are not being over-driven.  (unless you have some Really under-powered tweeters).
What you are experiencing, is just bad, low quality drivers.  And in some cases.. you can help to resolve this, by
simply lowering the treble dial, on your amp.   Or... using the software EQ,  that is available with your PCs soundcard driver.


 As Randy said... this sounds like a sort of filter like effect.   If its changing the values... its changing the way things sound
in a non-authentic way.   Typically when you do things like this... you RUIN the 3d Soundstage.  Though... the fact is
that so many people are listening on ECO-Garbage level speakers... that are incapable of being Accurate,  will never know
what a 3d Soundstage even is... let alone... the level of its capabilities.

 I think you were the ECO nut in one of the other posts... so it only makes sense, that you Shill for such Nonsense.

 Id put my old 1970s EPIs against ANY of your ECO trash speakers and FILTER EFFECT BS,  any day of the week...
and I guarantee that in a blind test of 1000 people... 1000 out of 1000... will choose the EPIs HANDS DOWN.
Not even a Chance of Competition.

 Trying to make badly made, cheap drivers... sound good, for the sake of saving a few watts, and pinching a few
pennies... is just plain Dumb.   Especially if you want to experience Actual high dynamic, high fidelity, audio.

[Xiaou2]

 As for the statement that People dont need good audio in their cabinets... and that old arcade games didnt have
high quality audio...

 That is a level of personal Opinion.  Some people not only play  Mr.Do  on their cabs... but they also might
play some more modern games.  Be it, various Console games... or a completely new game.  They also
might just enjoy using the thing to play music with, in the background.

 Its also very possible, that if the original game designers had their way... that they would have used
better speakers.   There are examples of certain innovative features.. such as in  Sega's Turbo, where
I believe there is both a left and right stereo output... as well as a 10" or so, large speaker in the bottom
of the cabinet, which mostly plays the rumble of the engine.


 Now... if you want to be completely Authentic to an arcade games sound reproduction... you would have
to build the cabinet very similarly to the original designs...  because these cabs tended to use the speakers
without any surrounding boxes.  The entire cabinet itself, could reverberate with sound, from the speakers
using its entire inner body of air... as its chamber.

 The the larger the volume of air in a speaker, the lower levels of bass that it can potentially hit.
As such... an entire cabinet worth of air volume,  can create quite the effect.  These cab designs
also tends to make a slight reverb like effect... which adds to that arcade level experience.

 You also tended to "Feel" the music more in these arcade cabinets.  A great example is Spy Hunter.
Just hitting the start button, and that "Whommmp" noise, reverberated strongly... through the cabinet.
The louder the volume of the game... the more of the effect that you heard and felt.

 You often do not need large and expensive drivers in typical close-range cabinets...
because you are so close to them... that you do not need them to be that loud, nor do you have
to worry about things like  long-distance  "room"  distortions.

 But... If your speakers are in fact very "Harsh"... then at close range... that harshness will be far
worse... and far more unbearable.

 A lot of arcade speakers were low spec fullrange speakers.  No separate tweeters.  So in fact, the games
that used them, were also designed to sound good, on those speakers.  When trying to play the game
with speakers that are completely different... you could very well be getting screeching levels of
highs... that would not be presented as such,  on lower quality full-range speakers (where a lot of
the sounds would be softened, blended and distorted... into a different type of sound).

 In that case, reducing the treble will probably be the solution, to maintaining the cabs ability to have
high fidelity audio.. and to also use it for lower quality audio games, without being too harsh.

[Zebidee]

Wow     Even though you guys don't understand the topics at all, you like ruining threads by posting rambling, unscientific monologue essays on topics you don't understand.

Simple facts then. Note that I use short paragraphs and sentences to avoid confusion.

Speakers have both resistance and inductance elements. Together, they add up to the speaker's "impedance", and it is why speakers have an impedance rating (measured in ohms).

High frequencies going through an inductor create high impedance.

Zobels are there to balance impedance at your amp's output (speakers). In the case of mid-range speakers, it mostly just stops your tweeters getting driven too hard. It isn't a "filter" as such, nor is it compression. It balances impedance.

Crossover networks are a little more complicated, but take advantage of same principles. In addition to balancing impedance, they direct the high frequencies to your tweeters and the low frequencies to your woofers.

Amps are typically designed to operate over a range of impedances, so is variable impedance a bad thing? Yes. Because your amp's power output varies depending upon this impedance. Because you end up over or under driving your amp and speakers, and actually lose audio content, so you get less out of your music.

Most better amps compensate for this somewhat by including crossovers and zobels in their audio output stages. Your treble and bass controls, your equalisers, are a part of this. Do you call them "filters" or "compression"?

Unfortunately, amp manufacturers can't put matching zobel terminations in your speakers (most people buy amps and speakers separately).

If you don't believe me, watch the video I linked, ask a true audiophile or just look it up yourself.

[Zebidee]

Trying to make badly made, cheap drivers... sound good, for the sake of saving a few watts, and pinching a few
pennies... is just plain Dumb.   Especially if you want to experience Actual high dynamic, high fidelity, audio.

In my experience, when people justify their position with the words "... is just plain Dumb", it means they don't really understand the topic, can't connect the dots, but also can't accept that.

It means you are describing yourself.

[RandyT]

Virtually every application I have seen for this circuit is to flatten the impedance curve on a woofer when used in conjunction with a crossover so that the low-end section behaves as it should.  If you are putting one on a tweeter and you find that it sounds better, it's probably not a very good tweeter.

When used on a single mid-range driver, the effect it has on the sound is simply as an automatic high frequency-attenuator.  As Steve said, the same effect can be achieved by using the EQ software on the PC or to a lesser extent, cutting the treble a bit.  The EQ is the better way, as it provides fine control, so you aren't just dumping everything down to flat indiscriminately.

For those who like nuts and bolts..

What happens with a zobel, as the freq rises the inductance increases, making more of the energy take the path of the cap and resistor. The higher the inductance the more energy will be dissipated in the resistor

In other words, high-frequency energy is attenuated, and you are basically pissing away part of your amplifier power as heat and limiting the response of the driver, for good or bad.  Makes perfect sense on the woofer of a multi-driver system with a crossover.  Not so much for a single mid-range driver.   And virtually none for any kind of decent tweeter.

BTW, compression also automatically attenuates frequencies, just much more of them in a precisely configurable way.

[Zebidee]

Virtually every application I have seen for this circuit is to flatten the impedance curve on a woofer when used in conjunction with a crossover so that the low-end section behaves as it should.  If you are putting one on a tweeter and you find that it sounds better, it's probably not a very good tweeter.

I really should have mentioned that it works well for the bass end too. However, it is best really for situations where you have a single mid-range speaker (or pair), perhaps with a built-in tweeter.

If you are using a woofer and/or separate tweeters, you should look at a full crossover network instead.

When used on a single mid-range driver, the effect it has on the sound is simply as an automatic high frequency-attenuator.  As Steve said, the same effect can be achieved by using the EQ software on the PC or to a lesser extent, cutting the treble a bit.  The EQ is the better way, as it provides fine control, so you aren't just dumping everything down to flat indiscriminately.

You are just "filtering", which you already made out like it is a bad thing, but with software instead. That option is still available to you whether you use zobels or not. Also, EQ won't do anything about high frequency oscillations created by the amp or the cables themselves.

What happens with a zobel, as the freq rises the inductance increases, making more of the energy take the path of the cap and resistor. The higher the inductance the more energy will be dissipated in the resistor

I never wrote those words, but you presented it like a quote, presumably from me. Which makes you a liar 

It is also not quite true. The energy will be dissipated one way or the other, via the resistor in the speaker or the resistor in the zobel. You aren't losing anything worth keeping. As I have already pointed out, zobels are about balancing impedance. Your amp wants constant impedance, it is designed that way.

If you have unbalanced impedance you can get oscillations/reflections on the signal line, especially at high frequencies, which probably won't sound good. Even if you can't hear it, you will be driving the amp harder. The amp's transistors may not be able to switch fast enough, so it may run hotter than it should or even fail. With some speaker/cable setups a zobel termination is essential. In some cases it won't add much, but it can do no harm.

Amps themselves can be the source of high frequency oscillations, mostly above audible frequencies, which can further damage the amp and/or speakers. Again, a zobel termination will dampen the oscillations and protect your gear, at least do no harm.

You talk like you are losing something with the zobel. All you would be losing is the frequencies that your speakers and/or amp can't handle at that volume, mostly just oscillations or signal reflections. If you want to hear that unpleasant noise, then leave them off. It is not about trying to improve "cheap" speakers, no speakers are perfect. It is about doing the best with what you have got.

Zobels (and/or crossovers, as appropriate) will help whether your speakers are cheap or expensive. If you have really great speakers that are specifically designed by a pro for your system, quite possibly with a zobel or crossover already in place and designed for your setup, maybe you don't need anything.

Have you ever heard about terminating video signals at the display device, often with a 75ohm resistor to ground? Well, this is very similar, though signal termination is less critically important for audio (as the frequencies are much lower).

I suggest you have a read of this article.
https://sound-au.com/cable-z.htm

Try it yourself. It is cheap, easy and safe. If you don't like the improved sound output, remove it.

However, TBH, I expect you won't. Apparently you know everything already! 

Just don't come back and spread lies.

[RandyT]

I never wrote those words, but you presented it like a quote, presumably from me. Which makes you a liar 

Settle down, Nancy, your name isn't in the quote tag and you weren't quoted in the post.  I found the description on the internet and didn't wish to take credit as though I wrote it.

You aren't losing anything worth keeping. As I have already pointed out, zobels are about balancing impedance. Your amp wants constant impedance, it is designed that way.

Most amps are designed to handle a range of impedances.  If it says to connect only 8-ohm speakers, the amp will be just fine with an 8-ohm speaker, Zobel circuit or not.

You talk like you are losing something with the zobel. All you would be losing is the frequencies that your speakers and/or amp can't handle at that volume, mostly just oscillations or signal reflections.

You are. Impedance changes translate to volume levels at those frequencies.  How it impacts what you hear is based specifically on what you are listening to. It is better and easier not to do a wholesale attenuation of those frequencies when you have a much better option available, the EQ of the PC soundcard.  The only place I can see value in them, outside of their intended use on a woofer/crossover application, is with something like a tiny flat panel TV speaker, where the TV offers no EQ capabilities.

[Zebidee]

heh, Nancy here.

You aren't losing anything worth keeping. As I have already pointed out, zobels are about balancing impedance. Your amp wants constant impedance, it is designed that way.

Most amps are designed to handle a range of impedances.  If it says to connect only 8-ohm speakers, the amp will be just fine with an 8-ohm speaker, Zobel circuit or not.

The actual impedances, when under load and with input, can (will) vary significantly from the nominal rating. Amps and speakers are electrical circuits, and all electrical circuits work better, for the long term, if working to a more constant load. Some amps may handle it better than others, but this is just plain-old common sense.

You have to consider how the entire system works together, amps, cables, speakers.

You talk like you are losing something with the zobel. All you would be losing is the frequencies that your speakers and/or amp can't handle at that volume, mostly just oscillations or signal reflections.

You are. Impedance changes translate to volume levels at those frequencies.  How it impacts what you hear is based specifically on what you are listening to. It is better and easier not to do a wholesale attenuation of those frequencies when you have a much better option available, the EQ of the PC soundcard. 

This is actually the whole point of the zobel exercise, to reduce volume of frequencies your speakers have trouble with, especially at higher volume. Done right, this means you can increase the volume (and bass & treble) of your amp's output without overdriving the speakers, so you get more of everything EXCEPT the frequencies your speakers cannot handle.

That's what I mean by you lose nothing. Get more for nothing. Another nothing way to look at it is everything wins, nothing loses.

If you try and don't like, just adjust or remove it.

If you want higher volume for those difficult frequencies, then clearly there are other ways to improve the performance of your system. Either by replacing the elements that don't work so well, or integrating them in a smarter way.

It is not a competition. Zobel terminations are just another tool for the kit.

You can do measurements and do the math if that is your way. However, you can also start with some basic values (say 104 ceramic cap and 4.7R or 10R 1W+ resistor) and just listen.

EQ software is OK for what it is, but remember that it is just attenuating/filtering at an earlier place, before the output. You would be losing the frequencies anyway, or even cutting stuff out that you don't need to. However it would not affect issues that may be occuring post-output from PC (amp, speaker cables, speakers). You can still use the software with zobels installed of course. Maybe you can find an improved combination solution.

[lilshawn]

wew lads.

man some of the worst people on the internet are...

linux users

political protolysers

and

audiophiles.

that said and out of the way. throw a 2.2 uf 100v non polarized cap inline on the tweeter. that should filter out most low and mid frequencies and create a rude highpass filter.

no sense driving sub and mid frequencies to a speaker not capable of reproducing them... all you do is force distortion.

[RandyT]

... and create a rude highpass filter.

Does it make the tweeter tell "off-color" jokes in a squeeky voice?  If so, I'm in.

 

[Xiaou2]

Ohh, I tried to watch the video.  It was basically some dude spouting mathmatical formulas.  Anyone
can spout a bunch of Techno Babble, and make it sound "Correct" and "Intelligent".  Just like the
falsified Climate data, that keeps getting outed by REAL scientist, that easily see through the BS.

 I never would claim to be an Mathematical genius.  But what I do have... is a High Caliber BS Detector,
and Common Sense.

 If what you are doing, is Auto Equalizing the Values... just to make it "Easier" for the amp... it comes
at a Price...   Just as Randy stated...  of altering the INTENDED SOUND / Volume  VALUES.

 I dont want my music TAINTED by Automatic Compression.  REAL AUDIOPHILES also do not want that
either!  Only fake Audiophiles, that probably own Bose or Klipshe  Eco-garbage speakers, might buy
into that Ridiculous BS.

 The people building $50K speakers, and high dollar amps, are NOT using this BS, for good reasons.
And, being that you said it was "Cheap",  that only proves it further.  As if such great performance could
be improved by a few dollars... then every speaker on the market would use them.  They dont.

 Amps that give a spec of 8ohms, are quite fine dipping down into the 6ohms or even below that
point, so long as such a load is not a constant.

 AND... the ohm dip is NOT what is causing your tweeters to be Grating and Distorted.  Its not the AMP
having issues driving them.  Its not any distortions between the amp, wires, etc.  Its a simple fact, that
your Tweeters are TOTAL GARBAGE.  Replace them with tweeters that are capable of the proper power
levels that you are after... rather than the Underpowered trash that is easily distorting, at mid to high
volume levels... and you will NEVER have that problem, ever again.

 I crank my EPI 100v speakers... and there is 100%  ZERO  Audible distortions.  They make the $3000
speakers at the local high end audio shop, sound like the cheapest Walmart boom box speakers, in
comparison.

 I dont Need to CHANGE the tweeters parameters.  The signal is Perfect as is.  Able to hear things in
music, that none of my other 30 speakers, are capable of being able to push out.

 And the simple fact is... unless you are listening to some $15 pc speakers, that can barely handle
8 watts of power... Most speakers and Amps, will NEVER suffer from the things that you speak of here.

 Will the amp struggle a bit more, with the ohm changes?  Possibly.  Does that really effect the quality
of the output of the sound?  Nope.  Not at all.

 In the worst case scenerio,  you attach 4ohm speakers to an 8ohm amp... that is not capable of
sustained 4ohm loads.  Guess what happens?   The amp cooks itself to its own Demise.  At that
point, you dont need to worry about any Distortions of the Tweeters!  >_<

 I accidentally cooked a Phillips woox boom box, that very way.  I was trying to test some Planer
speakers on them, not really thinking clearly about the ohm situation... as I was combining them
with the other speakers at the same time.  I should have known better... but my head was not in
the right place at that time.   It worked fine for maybe 10 min,  before destroying the amp completely.

 My 30 yr old Pioneer amp, however, is more than fine, with 4ohm loads.  And that includes 4ohm
speakers, that dip even lower than 4ohms, in usage.   Its still going strong, after 3 decades of
daily use (hooked up to my PC, and used all night long, every night).

 Maybe you should replace your $20 Barbie Branded karaoke Amp, with something that can handle
speakers that go above 2 watts of power, and you wont have these issues.

[Mike A]

But what I do have... is a High Caliber BS Detector,
and Common Sense.

That could be the funniest thing ever said on this or any forum.

[Mike A]

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xiaou2
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to
First, watch these:

""

""


Hollywood director Aaron Russo (Directed Trading Places w/ Eddy Murphy)

Russo goes in-depth for first time on the astounding admissions of Nick
Rockefeller, including 9/11 and the war on terror hoax, the Rockefeller's
creation of women's lib, and the elite's ultimate plan for world
population reduction and a microchipped society.

Also, search "New World Order" for a Lot of
links and proofs.

Before you get outraged, and shut youself down... Realize WHO this is
coming from. Hes a famous director, with no reason to lie.

Now, more...

===

USA Concentration camps built!



https://www.mindfully.org/Reform/2004/FEMA-Concentration-Camps3sep04.htm

===

American Holocost Trains:

http://www.issuesandalibis.org/campsd.html
http://www.whale.to/b/box.html

===

Poisoning & or +Weather Control


https://www.chemtrailcentral.com/chemfaq.shtml

Caused this and similar? (weather weapon)

https://www.taipeitimes.com/News/front/archives/2001/09/18/103423

===

Partial NWO plans Via Retired CIA Agent:

part 11


part 12


===

Army suicides highest in 26 years
https://news.yahoo.com/s/ap/20070816/ap_on_go_ca_st_pe/a

Coincidence?! Being asked to do the Unthinkable? Killed after job for
secrecy?

===

911 Scandal: Revealed Proofs
(search: "loose change 2nd edition full"


===

2008 Election Canceled?



===

Did you know that the FEDERAL RESERVE is not
owned nor controlled by the USA anymore?!

https://video.google.com/videoplay?docid=-515319560256183936

(search google vids for: "The Money Masters - How International Bankers
Gained Control of America"

===


Pass this INFo quickly to all you know. We
need to wake up, and band togther!