doody
doody's picture
Offline
Last seen: Never ago
Joined: Sep 5 2006 - 1:16pm
Test Tones
Editor
Editor's picture
Offline
Last seen: 13 years 4 months ago
Joined: Sep 1 2005 - 8:56am


Quote:
I am having doubts that the tweeter in one of my monitor audio speakers is defective . I would like to ask you people if there is a test tone that i can download to test and confirm if the tweeter is defective, I am almost sure that there is something wrong with the treble in the speaker but i have to prove it.

Play rock music with cymbals at normal levels, put your ear against the tweeters of both speakers. You should eaily hear the "wispy" quality if the tweeters are working properly.

John Atkinson
Editor, Stereophile

doody
doody's picture
Offline
Last seen: Never ago
Joined: Sep 5 2006 - 1:16pm

Hi John, Thanks very much for taking the time to to reply to my post, I really appreciate it. Perhaps if i give u a little bit of background info you can give me your opinion. The speakers in question are Monitor Audio RS6, hooked up to Roksan mono amps, I left it running for about an hour with XLO burn in cd track 9, the volume were set to bout 50%. when i came home I can smell something burning, I checked the amps and they were both working, i could not really trace where the burning smell coming from, i played the system and it worked but on one side it feels as you said that there was no nice whispy tereble as opposed to the other side.

It also worth mentioning that the entire system is less than 6 month old, it was out of service for almost 2 months as one of the monoblock amps went and i had to send it back to the dealer and according to him he replaced the PCB in both monoblock amps.

I am not really sure what is happening here, but i want to go to the dealer with a solid proof that at least the speaker is faulty and that is maybe due to the amp, so i am wondering if there is a test tone that will confirm that the speaker is defective.

Once more thanks for your help

Doody

CECE
CECE's picture
Offline
Last seen: 5 years 3 months ago
Joined: Sep 17 2005 - 8:16am

XLO "burn in" CD musta done what it's called!

Elk
Elk's picture
Offline
Last seen: 3 years 7 months ago
Joined: Dec 26 2006 - 6:32am

As this is a two-way speaker with a crossover at 3kHz the speaker will sound very dull if the tweeter is not playing.

A Google search on the phrase "test tones" will reveal many downloadable wave samples. Look for a 10kHz wav file that you can download, then burn it to a CD. 10kHz is easy to hear (even if you are of advancing age) and will be high enough that the woofer won't be producing anything noticeable. You should be able to hear this tone in both speakers if everything is normal.

doody
doody's picture
Offline
Last seen: Never ago
Joined: Sep 5 2006 - 1:16pm

thanks for all those who replied, specially EIK you have been quite helpful. let me tell you what i have done i crated test tones with a program called NCH tone generator from http://www.nch.com.au/action/index.html

i created multiple tones started with 1khz all the way up to 10khz. and burnt the wave files into an audio cd and i got 10 tracks from 1 khz to 10 khz

the suspected speaker played only tracks from 1 to 4 meaning tones from 1khz to 4khz, i could not hear anything from 5 to 10khz

the other speaker played all tracks no problem.

so definitely the speaker is defective but can we narrow it down a bit? i dont want to open the speaker as this will void the warranty plus i have never opened one before

jackfish
jackfish's picture
Offline
Last seen: 10 years 6 months ago
Joined: Dec 19 2005 - 2:42pm

Sounds like your tweeter is crossed over at around 4000Hz. Could be the tweeter or perhaps a cap or inductor in the crossover. Can you switch out the tweeter to the other speaker?

Elk
Elk's picture
Offline
Last seen: 3 years 7 months ago
Joined: Dec 26 2006 - 6:32am

Either the tweeter itself or the crossover components leading to the tweeter are toast. I vote for the tweeter as burn-in CD's often have a lot of high frequency energy which, if played even a little bit too loud, can be very hard on tweeters.

There isn't going to be anything that you can "fix" other than to replace the failed part. If you can order a replacement tweeter you may wish to do so. It isn't hard to swap them. As suggested, you can try swap the tweeters between the good and bad speakers.

However, it sounds like a good time to give the dealer a call and/or the manufacturer, tell them what happened and see what they will do for you. You didn't do anything unreasonable. They may just fix it for you or even swap out the failed one for a new good one.

As an aside, the crossover is probably at 3,000kHz as you can still hear up to 4,000kHz. Crossovers do not work as brick-wall filters with instantaneous cut-offs. Rather they have a "knee" or point where they start to fall off. Then the fall off gets bigger and bigger as the frequency goes higher. I bet the 4,000kHz sounds weaker then those before it, yes?

doody
doody's picture
Offline
Last seen: Never ago
Joined: Sep 5 2006 - 1:16pm

can this defect be caused by the amplifier? as i mentioned earlier each speaker is hooked up by one monoblock power amp. but one speaker is damaged and the other is ok ?

Elk
Elk's picture
Offline
Last seen: 3 years 7 months ago
Joined: Dec 26 2006 - 6:32am

It's possible one of the maps did something, like let a big transient through when initially turned on. Have you ever heard a biggish pop sound when you turn that amp on or off?

Other than this, amps generally don't hurt speakers unless something is really wrong with them or an underpowered amp is being used to play demanding speakers too loud and the amp is driven into speaker harming distortion.

doody
doody's picture
Offline
Last seen: Never ago
Joined: Sep 5 2006 - 1:16pm

Thanks for your replies, the reason i am trying to find out what is happening, is that the amps and the speakers are 2 different makes so i need to know if the speaker is defective bcoz of the amp is defective or the speaker is just a bad unit. If the speakers are too demanding to the amp, why only one speakers failed and the other is ok i think, taking into account that one monoblock amp is connected to each speaker, do u think it is that amp is what caused the problem? I just do not want to send the speaker for repair while the problem could happen again bcoz of the amp? Sorry to bother u guys like that with my problems.

Elk
Elk's picture
Offline
Last seen: 3 years 7 months ago
Joined: Dec 26 2006 - 6:32am

The amps are perfect for these speakers, nothing to worry about there. I doubt the amp has anything wrong with it. You could swap the amps to make sure that they both sound fine on the good speaker, but unless one of them is making largish popping sounds in the speaker when turned on and off I doubt the amp is a problem.

I really encourage you to go work with your dealer that sold you the speakers. There isn't anything you can do to fix the problem other than to dive into the speaker itself and it doesn't sound like this is what you want to do. Plus the speakers should be under warranty yet.

doody
doody's picture
Offline
Last seen: Never ago
Joined: Sep 5 2006 - 1:16pm

Elk, thanks a lot for your assistance in this matter, I took your advise and i contacted the dealer, when i told him about the problem he said you have played the system too loud and that has busted the tweeter, and this is considered as an abuse and not covered under the warranty. I am just surprised that the entire system has been matched by the dealer how come the tweeter will go bust around 50 to 60 percent of the volume? and should not speakers be provided with some kind of protection so that i won't go bust if over driven? also the MA RS6 could be bi-amped, if this is the situation how can a single amp blow the tweeter? thanks for your constant help

Doody

Elk
Elk's picture
Offline
Last seen: 3 years 7 months ago
Joined: Dec 26 2006 - 6:32am

It is possible to destroy a speaker by playing it too loud. If the volume control was at over half volume this would have been very loud - I don't know if this would be "too loud" however. Most speakers start to sound compressed and unhappy when played too loud. The difficulty here is that burn-in CD's sound weird anyway so it is hard to judge.

Many speakers don't have any protection from too powerful of a signal - some have fuses but most don't as many feel that the fuse compromises the sound.

You may have overdone it as your amps do have a good amount of power for these speakers. They are a good match but it would be possible to play them too loudly for their own good.

Will they work with you to get a good price on the repair or get you the tweeter for a reasonable amount? It may not be that big of a deal.

CECE
CECE's picture
Offline
Last seen: 5 years 3 months ago
Joined: Sep 17 2005 - 8:16am

Ya probably clipped teh amp and cliupped test tones is a way to fry teh tweeters. Proves my point, never too many watts, but easily too few. And why are you playing test tones, eeessshhh. Play music and for go all the burn in nonsense, it's dumb, does nothing but obviously damage tweeters, and return the XLO "burn in " disc...that's beyond snake oil...it's RETARDED. It should be labeld burn out disc.

Editor
Editor's picture
Offline
Last seen: 13 years 4 months ago
Joined: Sep 1 2005 - 8:56am


Quote:
i contacted the dealer, when i told him about the problem he said you have played the system too loud and that has busted the tweeter, and this is considered as an abuse and not covered under the warranty.

Frankly, I think your dealer is full of it. If the amplifier wasn't being clipped and wasn't faulty (ie, pumping out RF oscillations) then it must have been a tweeter manufacturing problem. The fact that the other tweeter didn't fail in identical circumstances suggests that the failure wasn't due to abuse.

In my humble opinion, this is a warranty repair job.

John Atkinson
Editor, Stereophile

Jeff Wong
Jeff Wong's picture
Offline
Last seen: 13 years 3 weeks ago
Joined: Sep 6 2005 - 3:28am

If doody is using high capacitance speaker cables or interconnects (i.e., Goertz) wouldn't oscillation be a possibility? I'm also wondering if the tweeter damage occurred when one of the monoblock amps failed (before both had their PCBs replaced).

doody
doody's picture
Offline
Last seen: Never ago
Joined: Sep 5 2006 - 1:16pm

John Atkinson, Elk and Jeff wong, thank you so much for your reponse and support in this matter. I am using Roksan speaker cables and interconnects, which is recommended by roksan the amp makers.

Actually the dealer is really a bad one he has given me a real hard time, even when the first monoamp failed the dealer missed me around to get it repaired under warrnty, and i just so happen to be very lucky and had a business trip to London England and i met with Mr. Tourage the MD of roksan who spoke to the dealer and got the amps repaired under warranty. the problem is i am not going to London anytime soon and i am not really sure how I am going to handle this issue with he dealer, how i wish someone from roksan can see the responses on this web site.

One more thing may be it is worth mentioning, is that even after the PCB boards were replaced, one of the monoamps will always trip and wont work again unless it is switched off and back on from the power switch. the mono amp did it all the time i played steve ray vaughan the song" The pan ally" his album couldn't stand the weather. which i like to play around 60% of the volume. and i did swap the amps i mean left to right and right to left and still the same amp tripped. I really do not know what does that mean.

Again thank you so much for your reposes and support it really meant alot to me.

Love
Doody

Monty
Monty's picture
Offline
Last seen: Never ago
Joined: Sep 16 2005 - 6:55pm

Swapping the speakers from side to side and the amps from side to side should isolate the offender. If the problem moves with the component then the component is the problem.

I've had a few tweeters simply give up for no reason and they are a snap to swap out. If the dealer won't step up then I would suggest contacting the speaker manufacturer and explain the situation. I wouldn't be surprised to find out they sent you a new tweeter for free. Even if they don't, I suspect it's not an expensive tweeter.

A lot of speaker companies source their drivers from someone else. Scanspeak, Vifa, Dynaudio and others supply drivers to speaker companies and if you can pop yours out and determine which model you have then you can google the driver and check on replacement prices. Many aren't expensive and a big cost in speakers is the cabinets as opposed to the drivers.

CECE
CECE's picture
Offline
Last seen: 5 years 3 months ago
Joined: Sep 17 2005 - 8:16am

I play SRV at levels he did live!!! And AVA amps never never do anything but sound great...Roksan...yupper.... AVA is a lot closer in MN too. So using audio stuff to reproduce music at realistic levels is wrong? Why would someone buy the stuff if you can't make it real? Sounds like Roksan is some flakey stuff? Try stuff not made in England See, CROWN is a better amp also, I don't think Crown would ever say, you played it too loud!!! Time to change your amps. www.avahifi.com

cyclebrain
cyclebrain's picture
Offline
Last seen: 2 months 3 weeks ago
Joined: Jun 16 2006 - 11:40pm

The clipping reason makes sense, lots of harmonic energy can be created in a wide and continuous range of frequencies.
The RF frequency reason is less likely. As the frequency increases the inductance portion of the voice coil will begin to overwhelm its resistive value (8 ohms or such).
At RF frequencies increased tweeter impeadance values will act like a low pass filter and reduce the energy to the driver. A good thing for makers of class D amplifiers with their output of high switching frequencies.
Also while RF energy from an amplifier could have significant energy, stray RF picked up by a speaker cable would not have much energy. If it did I would use all that RF power available to power something like my home.

doody
doody's picture
Offline
Last seen: Never ago
Joined: Sep 5 2006 - 1:16pm

Guys I can't thank you enough for this, now then even if i have to replce the damaged tweeter at my expense, it is ok I will do it, but I somehow believe that is not going to fix the problem for the following reasons:

when I played stereo or even mono recording and the volume level is about 50% a very strange thing happens to the monoblocks one of them would trip and the other won't. what i mean by tripping is that the amp would go to the so called safe mode, and in order to bring it back to operation i have to switch the power off and then back on. The manufacturer called this a safe mode???
I do not know what the safe mode means? is it a protection set on the amp to power it off if it starts clipping or to prevent it from over driving the speakers?
Whatever the safe mode is I can only say it is not safe enough if it is safe at all.
At the moment I personally believe that there is something that is causing the amps to behave erreatically and both the manufacturer and the dealer are offloading the problem on each other and the easyway out for both of them is equipment abuse.

What i do not understand is whatever the safe mode is why both amps won't go to it in the same time?

CECE
CECE's picture
Offline
Last seen: 5 years 3 months ago
Joined: Sep 17 2005 - 8:16am

Read the manual on the amps......to find out what they call safe mode. Is it seeing a load it can't deal with, or is the input over driving the amp...is it an input problem or a load problem..READ the MANUAL.what causes teh amp to go into safe mode. Could be this or that. Maybe something in teh amp or pre amp causes teh amp to shutdown, and it also took out teh tweeter, or is the speaker a defective load to the amp and it's causing it, a bit of logical troublshooting should be able to find it.

doody
doody's picture
Offline
Last seen: Never ago
Joined: Sep 5 2006 - 1:16pm

Hello Dup, here is what i found in the manual, what they call it a protection mode not a safe mode.

CECE
CECE's picture
Offline
Last seen: 5 years 3 months ago
Joined: Sep 17 2005 - 8:16am

So it could be a fault from many sources, you are back to the start line, what is causing it to do this? Could be the load seen, the input overdriving it, or an internal fault of the amp. hmmm, time for some logical troubleshooting to narrow it down, swap channels, swap inputs, swap outputs etc etc to narrow it down, see where teh faults move or stay always on teh same amp chanell with different output load or different input, if it stays always on same amp chanell you have an internal amp fault...

doody
doody's picture
Offline
Last seen: Never ago
Joined: Sep 5 2006 - 1:16pm

I swapped the amps and the fault moved with the amp however, the speaker has gone defecctive at the side which did not go to the protection mode.

Jeff Wong
Jeff Wong's picture
Offline
Last seen: 13 years 3 weeks ago
Joined: Sep 6 2005 - 3:28am

If I'm understanding this correctly, one speaker got fried by the amp that was acting funny. You switched the amps and now the non-defective amp clearly shows that the speaker that was associated with the funny amp is fried? I'd be careful that the funny amp doesn't cook the speaker that used to be with the good amp.

CECE
CECE's picture
Offline
Last seen: 5 years 3 months ago
Joined: Sep 17 2005 - 8:16am

So you have 2 defective tweeters? And one bad amp? Maybe the amp took out both tweeters, this is getting confusing. OR your test disc blew both tweeters. When teh tweeter went bad on teh first one maybe it shorted and took out teh amp, all kinds of could be this or that. Seems to me don't run test discs if you ain't in teh business of repairing the stuff where you need test signals, let alone the ABSURD NONSENSE of burning in a system with TEST TONES!!! It's nuts, and more made up nonsense by marketeers who came up with another audio scam. The tweeters whoudl easily be poped out on most speakrs, few screws possibly soldered on leads, sometimes terminals, www.madisound.com and many other vendors sell stuff for exact replacement if not stil under warranty. Lotsa speaker companies send out replacement drivers for teh customer to install, easy job. Sounds like you have a few defective components, one amp a few tweeters. Get teh amp fixed before you keep poping tweeters?

cyclebrain
cyclebrain's picture
Offline
Last seen: 2 months 3 weeks ago
Joined: Jun 16 2006 - 11:40pm

Is it possible that when an amp goes into protection mode it creates a nasty transient? Yea I know that it shouldn't.

Elk
Elk's picture
Offline
Last seen: 3 years 7 months ago
Joined: Dec 26 2006 - 6:32am

Good thinking. A transient at this point could choke a tweeter.

doody
doody's picture
Offline
Last seen: Never ago
Joined: Sep 5 2006 - 1:16pm

Does anyone know where to download the service manual for thr rs6 or how to replace the tweeter and the crossover? And if this has to be done by a specialist?

Log in or register to post comments
-->
  • X