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Dustin_Broke
06-19-2011, 03:50 PM
This is pretty sound advice. All speakers change impedance as they produce sound depending on the frequency they're at and the quality of the crossover. Your amp will dynamically change the load output as well. If this gets to be too dynamic and the power supply cannot keep up, you might burn it up.

However, most receivers are capable of handling this dynamic impedance. If you're trying to mis-match impedance with 8,6, or 4 ohm speakers all in an odd combination, you will then very likely cause problems. I have run a 4 ohm center, 6 ohm L&R, and 6 ohm rears on my cheap Yamaha receiver. It ran it just fine. My receiver actually has a setting to change its output impedance to match 6 ohm speakers. I used that setting and everything was fine. For a $300 receiver, this is a nice feature. I would look into your system and see if you have a similar setting.

*EDIT* After seeing that pic, are those small speakers the ones you are running? That will not be a problem at all. Just make sure you don't give them too much volume as you could blow the tweeter with too much power. Tiny speakers like that will not put too much load on the amp that would damage it. However, the amp could possibly put out too much power if you crank it too high. I wouldn't worry about the impedance numbers here.


Someone said this and I just wonder if this is true that my JBL Control 1 speakers that are 4 ohms will be totaly ok to use on a normal 8-16 ohms Sony receiver. Basicly this is the pic I showed.

Basicly you can see my receiver and 5 disk CD changer and also my left speaker but not the right. I use my stereo system as my computer speakers mainly. You can see part of my Sony notebook on the lower right of the pic. So these speakers are compact. They have a 5.25" woofer and it's a 2-way speaker system. If you just measure the moving parts then it's just 4in woofer. The tweeters are 3/4" and they are Polycarbonate dome tweeters.


hmm strange somereason my pic won't show even it says it's uploaded.

Dustin_Broke
06-19-2011, 03:55 PM
I just noticed some people say this and that about my setup and I don't know what is the true fact. I asked this on some other forums but everyone says differently.

JohnMichael
06-19-2011, 04:15 PM
Someone said this and I just wonder if this is true that my JBL Control 1 speakers that are 4 ohms will be totaly ok to use on a normal 8-16 ohms Sony receiver. Basicly this is the pic I showed.

Basicly you can see my receiver and 5 disk CD changer and also my left speaker but not the right. I use my stereo system as my computer speakers mainly. You can see part of my Sony notebook on the lower right of the pic. So these speakers are compact. They have a 5.25" woofer and it's a 2-way speaker system. If you just measure the moving parts then it's just 4in woofer. The tweeters are 3/4" and they are Polycarbonate dome tweeters.


hmm strange somereason my pic won't show even it says it's uploaded.




Maybe if you can add a manufactuers link showing the receiver that might help. I have had trouble posting pictures that I can only see with my iPhone3GS.

bfalls
06-19-2011, 04:25 PM
Hi dustin. In general, yes it should be OK. The minimum power the JBLs required for normal listening levels should be well within the capabilities of the receiver.

I can't tell which Sony receiver you have, but it looks like a multi-channel AV receiver. Depending on the rated total wattage it should be more than capable. The problem with four ohm speakers is they require more current. I wouldn't drive them to party or concert levels, but normal listening should be OK.

Dustin_Broke
06-19-2011, 04:52 PM
The model for the receiver I have is a Sony STR-D715.

All I know is that the volume has numbers 1-10 and 3 dots between each number. If I have to volume past 5 then my speakers are close to max since the SK3 lamp starts to light up when the bass hits. Basicly my crossover has a sonicguard and it protects the speakers from blowing them. The lamp will go out if I put too much power then no sound will come out of the speakers and I have to replace the lamp. Basicly I mostly have it around between 3 and at most around 4 and 2 dots so almost 5. But when I have my music around 4 dots or close to 5 the receiver does get kinda hot but nothin happenes to it like it won't goto protection mode or anything so I assume I should be ok if I don't have it louder than 5 right? Eatherway if I have it louder than 5 then I will blow the fuse on the crossover since I will be playing it too loud for the speakers.

Do you guys think I will be fine if I play at the levels I play when I listen to my music loud? I know that if I have the volume around 3 or less then it's not as hot btw. But it seems like it works fine even at 4 or 4 and half at most.

Dustin_Broke
06-19-2011, 04:59 PM
Usualy on most receivers I play around 45% on the dial at most and never go over 50. I am basicly saying 0-100% and 0 is no sound and 100% is full blast. If the receiver is rated 80 watts per channel or 100 watts per channel then I never go higher than 50%

Dustin_Broke
06-19-2011, 05:07 PM
I wasn't able to upload the whole PDF file of the specs for my receiver since it's too big but I did use print screen and took a shot of the specs on my adobe reader. I hope this will show.



http://i30.photobucket.com/albums/c337/Vanillaice378/Pics/Sonyreceiverspecs.jpg



One thing that is strange is that it says that on the STR-D715

220 W + 220 W (4 ohms)


But does that mean it will run 4 ohms? Or does this have nothing to do with the speakers? It says they are 80 watts per channel on 8 ohms and THD 0.8% at 1 kHz.

Dustin_Broke
06-19-2011, 05:45 PM
Is it better to get a used receiver like that is from Kenwood that has a ohms switch? I can set it to something like less than 8 ohms or 8 ohms or more.



All I know is someone said that since my speakers are small I won't have to worry about ohms. But I don't know if that person is a expert on stuff like this. Basicly people say this and that about ohms so it's confusing.



If my current receiver will work fine then that would be great but if it will be a better choice to get a receiver that has the switch then I should get that.


Here's a pic of my stereo and my JBL Control 1 speakers you can't see the right speaker btw.

http://i30.photobucket.com/albums/c337/Vanillaice378/Pics/DallasStuff001-1.jpg

Mr Peabody
06-19-2011, 08:51 PM
You are fine running the JBL's, you are already doing it successfully and the fuse is there for protection if the receiver is driven too far. Keep in mind that 0 to 100% on a volume control isn't exactly linear and many receiver's amp will max out it's power sometimes as early as 1:00 on the dial or maybe 70% up. Unless you are blowing a lot of fuses or the heat seems obsessive like you can't keep your hand on the Sony then I wouldn't worry about it.

A power rating into 1k is only with a 1k tone, musical bandwidth is 20Hz to 20kHz, so a rating at that is more realistic.

If you want a receiver that handles low impedances Onkyo would be the one.

Dustin_Broke
06-20-2011, 02:26 AM
Well the fuse is on the JBL speakers I don't know if there is one for the receiver. I assume that the receiver will goto protection mode if it gets too hot. I do have a service manual for the receiver but it's around 11mb so I can't upload it here since it's too big but maybe you can see if there is a fuse or protection mode for this receiver. Do all Sony receivers have protection modes normaly?

Mr Peabody
06-20-2011, 04:20 PM
If you are blowing fuses on the speakers it's a definite sign the receiver is being driven too hard, into "clipping", which means the signal becomes distorted. Be thankful for those fuses or you wouldn't have any tweeters right now. Clipping will take a tweeter right out.

With that being said you still have no issue as long as you are satisfied with the volume you hear when the receiver is below that point where you know you are going to blow a fuse. If you are not satisfied there's two ways you can go, new speakers that are more efficient/sensitive, for instance if the JBL are 88dB efficient try to find a speaker above 90dB, listen to Klipsch or Cerwin Vega, the second way is a better receiver with more power or power truer to spec. You will find that watts are not all created equal. If the JBL are above 90dB then your only path is another receiver. Or, if the Sony has preamp outputs add an amplifier. Sometimes adding a sub will help by filling in that bottom end slam so you don't have to drive the mains so hard.

Dustin_Broke
06-20-2011, 06:05 PM
Well I know that this Sony receiver is powerful enough to power bigger speakers since I use to connect them to bigger ones and had no problem. I don't think the receiver was going to clipping it was the speakers getting close to max and likely I would blow the woofer first if the fuse wasn't there since I play alot of bass tester songs. The amp is powerful enough and it does play clean and loud. But the point of this topic was to make sure that having 4 ohms speakers connected to a 8 ohms receiver was fine. But I guess it will be fine if I don't have it super loud but eatherway there is no way I can have it super loud since these speakers are small bookshelf size. Now if I had a bigger speakers that is also 4 ohms then probley if I have the receiver too high the receiver might go onto protection mode.

Basicly if you guys are saying that having the receiver very loud will overheat then probley my speakers are fine since eatherway I can't turn it super loud since these speakers isn't like 200 watts. It's around 80 watts or 100 watts at most. It says 150 watts pink noise continuous power but I really don't think you can have them that loud for a long long time. It did say they tested it in a 2 hour duration so probley if you keep it around 150 watts more than that it might blow them I don't know.

Mr Peabody
06-20-2011, 08:04 PM
Well if that was the point it was already answered, so how much reassurance do you want?

Are these your speakers:
Description 2-Way, 4-Inch (100mm), Personal-Size Monitor Loudspeaker
Series Control
Finish Black
Frequency Response 80Hz 20kHz
Power Handling 10 Watts 80 Watts
Low-Frequency Driver 4", Shielded
High-Frequency Driver 1/2" Titanium-laminate dome, shielded
Sensitivity (2.83V/1m) 89dB
Nominal Impedance 8 Ohms
Dimensions (H x W x D) 9" x 6-1/16" x 5-7/16" (228mm x 155mm 139mm)
Weight 5.2 lb (2.4kg)
Updated: September 01, 2009
Technical Specifications
+ Specifications open
FeatureName FeatureValue
Crossover Point
Crossover Slope
Power Handling 10 Watts 80 Watts
Max. Recommended Amplifier Power
Low-Frequency Driver 4", Shielded
High-Frequency Driver 1/2" Titanium-laminate dome, shielded
Low-Frequency Transducer
High-Frequency Transducer
Ultrahigh-Frequency Transducer
Sensitivity (2.83V/1m) 89dB
Nominal Impedance 8 Ohms
Dimensions (H x W x D) 9" x 6-1/16" x 5-7/16" (228mm x 155mm 139mm)
Weight 5.2 lb (2.4kg)
Description 2-Way, 4-Inch (100mm), Personal-Size Monitor Loudspeaker
Series Control
Finish Black
Speaker Configuration
Frequency Response 80Hz 20kHz
Crossover Frequencies
CONTROL ONE

If so, they are 8 ohms, and I agree a 4" speaker with a low frequency cutoff of 80Hz isn't going to handle much big bass program. .

Dustin_Broke
06-21-2011, 05:10 AM
Here is a link to the speakers I have.


http://www.avstumpfl.com/common/datadb.php?id=1&table=audio_speaker_front&offset=1

bfalls
06-21-2011, 05:41 AM
I have a Sony STR-D5300ES (120W/ch 8ohm). I've had it connected to different speaker systems. The longest with Legacy Focus (4ohm). The Legacy's are about 94db efficient. I've never had the first problem driving them in stereo direct or surround. I'm more into quality than quantity, but I like to crank it once in a while. You have to crank it listening to Pink Floyd's Dark Side of the Moon and immerse yourself in the middle (I think it's a state law or something). The Sony ES series will crank.

I've upgraded to Emotiva UMC-1 and XPA-5, but still use the Sony in my secondary system driving Klipsch Kg4 mains, KV3 center and RS-3 surrounds. I know the Kg4s were originally 4ohm (relabeled to 6ohm for international sales).

I also have a Yamaha RX-V2095 (100W/ch) which handles 4ohm loads without any problem. The Sony and the Yamaha were either the flagship of the series or the next one lower.

TheHills44060
06-21-2011, 10:08 AM
I used to have a Sony STR-D6?? (can't remember the last 2 digits) and drove big ole 4 ohm Pioneer truck speakers to dorm room loudness levels without any problems. Granted it was older than the model you have but still along the same product line I figure so I don't think you'll have an issue.

Mr Peabody
06-21-2011, 05:43 PM
Your speakers only go down to 120Hz so you are missing some serious low frequencies. They are also rated at 87dB efficient which will require some power to play at loud levels. I still believe it was the receiver clipping that blew your fuses. Either way though as I stated earlier if what you are getting from your receiver and speakers are satisfactory volume to you then the set up will be fine. It's not going to hurt anything to run the 4 ohm speakers within the limits. Given the 120Hz low end cutoff I would recommend a sub. For your set up the sub wouldn't have to be anything too big.

The above mentioned speakers at 94dB would play much louder than yours at 87dB with the exact same input signal. You might find this interesting: http://www.animations.physics.unsw.edu.au/jw/dB.htm

Dustin_Broke
06-21-2011, 06:28 PM
Yes the main frequency response is from 120hz - 20hKz +/- 3db

Usable frequency reponse down to 70hz but it's -10db

It says that there is usable frequency response down to 70hz on the spec sheet.




"Frequency response shall be within plus or minus 3 dB from 120 Hz to 20 kHz.
Usable frequency response shall extend downward to 70 Hz."



Just wanted you guys to know this info too.

Dustin_Broke
06-21-2011, 06:38 PM
Btw I did use these speakers on a different receiver that accepts 4-16 ohms and when I have it up the speakers does the same thing when the bass hits. I don't think it's the receiver doing clipping out. It's the speakers maxing out since I am putting to much power. But I don't have that receiver anymore. It was a old receiver made around 1992. I remember it was a NEC. I also tried some Kenwood receivers that have a Ohms switch and even I set it to less than 8 ohms it does the same thing.


The JBL Control 1Xtreme is basicly the same speakers but just has a crossover designed for most receivers since it's 8 ohms. They did put titanium-laminated dome tweeters instead of just plan polycarbonate dome tweeters and because of that they made the crossover down to 4000hz instead of 6000hz like the one I have. The woofers are made the same and the cabinet also. But I think since the Control 1Xtreme is 8 ohms they made the sensativity 89db instead os 87db since 8 ohms speakers aren't as loud as 4 ohms. I noticed that 4 ohms speakers don't need to have the volume turned up as loud as 8 ohms speakers but if the sensativity is 89db then it will make it loud as a 4 ohms that is a 87db.

Mr Peabody
06-21-2011, 06:39 PM
Thanks for sharing but read the link I posted, 10dB down is really not "usable". 3dB down is a very noticeable decrease. I'm sure the speakers kick in the midbass, they are JBL, and designed for Pro application with a great power handling I only mention the lack in the bottom end for your information and possible future upgrade, especially when you talk about test bass program.

Dustin_Broke
06-22-2011, 02:06 PM
I decided to do this. What I' am going to do is sell my JBL Control 1 speakers that are 4 ohms and get the JBL Control 1Xtreme since that speaker is 8 ohms and then I will have no more worries about ohms. I do really like the sound of the Control monitor speakers but just was worried that I would damage my nice Sony receiver because of it. I did but a used and execelent condition pair of the Control 1Xteme. As I said on the last post I made both speakers are the same but just one is 8 ohms and other is 4 ohms and one has titanium and one has polycarbonate tweeters.


Then in the future since most receiver are 8 ohms or higher I won't have to worry about ohms anymore. :)

bobsticks
06-22-2011, 02:21 PM
Aren't you worried that the switch from polycarbonate to titanium tweeters will increase the shrill upper frequencies to an unacceptable level while limiting the all-important bass frequencies? Your musical selections tend to be bass dominant. Ther may be, at the least, reason for concern.

It's nice that the brochure has instructions for rotating the logo though.

Dustin_Broke
06-22-2011, 02:40 PM
Pretty much all control series can have the JBL logo rotated to how you have it set. Are you saying titanium-laminate dome tweeters are going to sound the same as polycarbonate dome tweeters? Basicly the Control 1Xtreme uses a thin film of titanium coated over polycarbonate. I didn't think it would make much difference in that case but will it sound different just because one has a thin coating of titanium over the polycarbonate dome tweeters?





This is where I got the speakers. They look exactly the same as the Control 1 but just the Control 1Xtreme has titanium coated polycarbonated dome tweeters. The seller had two pairs and I just got one pair.


http://cgi.ebay.com/JBL-Control-1X-1Xtreme-Speakers-Pair-Black-/230629998655?_trksid=p5197.m7&_trkparms=algo%3DLVI%26itu%3DUCI%26otn%3D1%26po%3D LVI%26ps%3D63%26clkid%3D835652061482419251






But I guess what I want to know is that will it really make a difference on sound just because one has the titanium coating polycarbonate and one has just polycarbonate?


If you guys still think that JBL Control 1 I have it better then I can just not sell it but I thought it was best to get something that is 8 ohms and that is basicly the same speakers.

Dustin_Broke
06-22-2011, 05:45 PM
Just wondering but is this true that if I use 4 ohms speakers to a 8 ohms receiver it will make alot of distortion? Someone just said that on a different forums and wanted to make sure thats true. Since if it is true then I should use the Control 1Xtreme. But maybe that person is wrong and 4 ohms to a 8 ohms won't have any distortion since it seems like everyone says something differently about 4 ohms speakers to 8 ohms amp/receiver.


I can always resell the Control 1Xtreme if the one I have is better but I just need to make sure that forsure 100% that 4 ohms speakers will sound and work fine with a 8 ohms receiver. I just don't want to overheat the Sony receiver. But if I did overheat it it would go onto protection mode right? It has never done that so far yet even I used it for almost 7 days.

Dustin_Broke
06-23-2011, 12:24 PM
Ok I did a test on the Sony and played my music very loud almost to the point were the SK3 lamp starts to light for 8 min and the receiver did get hot but nothin happened so I guess that means 8 ohms receiver can handle 4 ohms but just gets really hot. I thought it would go onto protection mode but it didn't. Also the Kenwood receiver was the same too.

pixelthis
06-23-2011, 02:21 PM
Well I know that this Sony receiver is powerful enough to power bigger speakers since I use to connect them to bigger ones and had no problem. I don't think the receiver was going to clipping it was the speakers getting close to max and likely I would blow the woofer first if the fuse wasn't there since I play alot of bass tester songs. The amp is powerful enough and it does play clean and loud. But the point of this topic was to make sure that having 4 ohms speakers connected to a 8 ohms receiver was fine. But I guess it will be fine if I don't have it super loud but eatherway there is no way I can have it super loud since these speakers are small bookshelf size. Now if I had a bigger speakers that is also 4 ohms then probley if I have the receiver too high the receiver might go onto protection mode.

Basicly if you guys are saying that having the receiver very loud will overheat then probley my speakers are fine since eatherway I can't turn it super loud since these speakers isn't like 200 watts. It's around 80 watts or 100 watts at most. It says 150 watts pink noise continuous power but I really don't think you can have them that loud for a long long time. It did say they tested it in a 2 hour duration so probley if you keep it around 150 watts more than that it might blow them I don't know.

one misconception you have...that a speakers size is whats important.
I HAVE seen small speakers with inefficient drivers that are
receiver killers, and huge speakers you could run on a clock radio.
AND the impedance used to be a lot more important than it is now.
On receivers that are more honest with their amperage its less important, on a receiver with IC amps and designed at
the margins its more so.()sony)
RECEIVERS tend to have one power supply, the amps that it turns out is all of the power you will ever have , and matters
more than watts, which is why they use watts.
BETTER amps have separate power supplies for each channel,
typical in separate amplifiers , nonexistent in receivers under a grand.
EMOTIVA has a cheap (but not shoddy) amp with 125wpc,
around 350 bucks, highway robbery, an amp like this
should be at least five hundred bucks. LIKE most separates it
will run both four and eight ohm speakers, improve the sound of your system immensely, and improve your life overall.
Any separate amp will do this, but the Emo is just the best bargain. I WAS A SKEPTIC, but now a believer.
Anyway I WOULDN'T worry about it much, most receivers run
a little hot these days, ANYWAY.
Just enjoy, and get a sub. You need a sub.:1:

bobsticks
06-23-2011, 02:35 PM
I didn't think it would make much difference in that case but will it sound different just because one has a thin coating of titanium over the polycarbonate dome tweeters?

Yes. It will sound different. The introduction of any metal, be it titanium or beryllium or whatever, will add a tinny quality to the upper registers of reproduced sound.

To answer your follow up question; no, playing a 4 ohm speaker through an 8ohm receiver will not necessarily create distortion.

The problem that you have will have nothing to do with the power supplied to the speaker. The problems you'll encounter will be due to the lack of size of the speaker enclosure combined with the added titanium coating.

For instance, the Focal Grand Utopia with beryllium tweeters will have the same sound characteristics in the upper registers as your JBL's...both will have issues with a tinny resonance and "piercing" quality. On the Focal, some of this is negated by the significantly larger enclosure which adds greater bass elements to the overall sound.

Basically, your JBL's will sound like the Focal Grand Utopias but without the bass.

SlumpBuster
06-23-2011, 03:59 PM
None of these cowboys know what they are talking about Spanky!

If you mix 4 ohm speakers with an 8 ohm receiver, it is a fire hazard! Your speakers will catch fire, your plastic dinosaurs will melt, your house will burn down and your mother will cry! Why do you want to make your mom cry?!?! Why, oh, why? Oh, the humanity!

Either that, or they will work just fine until a thermal protector kicks in...but I could be wrong.

Dustin_Broke
06-23-2011, 04:05 PM
Yes. It will sound different. The introduction of any metal, be it titanium or beryllium or whatever, will add a tinny quality to the upper registers of reproduced sound.

To answer your follow up question; no, playing a 4 ohm speaker through an 8ohm receiver will not necessarily create distortion.

The problem that you have will have nothing to do with the power supplied to the speaker. The problems you'll encounter will be due to the lack of size of the speaker enclosure combined with the added titanium coating.

For instance, the Focal Grand Utopia with beryllium tweeters will have the same sound characteristics in the upper registers as your JBL's...both will have issues with a tinny resonance and "piercing" quality. On the Focal, some of this is negated by the significantly larger enclosure which adds greater bass elements to the overall sound.

Basically, your JBL's will sound like the Focal Grand Utopias but without the bass.

So I guess it's not good that the Control 1Xtreme uses titanium coating and makes it sound like there is less bass and have more tinny sound? Since the way you said it sounded like the Control 1 speakers should not use any metal on the tweeters and only use plain polycarbonate dome tweeters since the enclosure is small. Or did I missunderstood you?

Dustin_Broke
06-23-2011, 04:25 PM
All I can say is that if it's not going to sound good as the Control 1 I have then maybe I should just resell the Control 1Xtreme on Ebay. I thought basicly they are the same speakers but just one is 4 ohms and other is 8 ohms.


Eatherway it seems like the best choice is to keep the Control 1 I have that is 4 ohms since it probley sounds the best just because the tweeters don't have an metal coating to make that tinny sound of something.

Mr Peabody
06-24-2011, 05:13 PM
Dustin, you always talk as if you don't have these speakers or something, for goodness sakes hook them up one pair at a time and compare for yourself. It's good to get advice but when you have both sets right there.... listen and trust your own ears. When the speaker is in balance I personally like titanium.