Quick ask here, say iv got a pair of 6 ohm speakers and a
8 ohm amp, I understand shouldn't be used together so my query is is there a way of changing the speakers to 8 ohm or higher for safety? I know I could run them in series with another set to increase impedance but is there and resistor based tricks or the like which may help?
Thanks
8 ohm amp, I understand shouldn't be used together so my query is is there a way of changing the speakers to 8 ohm or higher for safety? I know I could run them in series with another set to increase impedance but is there and resistor based tricks or the like which may help?
Thanks
You need to buy an amplifier with either 6ohms or 4ohms capability. (this does NOT mean capable of driving a 6r0 or 4r0 resistor).
But check your speakers.
They may be 4 to 8ohms speakers and not 6ohms.
The bass mid driver is often 4ohms in a modern two way, coupled with an 8ohms treble.
This type needs a 4ohms capable amplifier.
But check your speakers.
They may be 4 to 8ohms speakers and not 6ohms.
The bass mid driver is often 4ohms in a modern two way, coupled with an 8ohms treble.
This type needs a 4ohms capable amplifier.
They are wharfdale 3xp speakers and I'm informed the impedance stated is usually pretty accurate. Ok so no changing speakers but is I used another set of speakers, say 4 ohm ones wired in together to make 10 ohm and the amp is 8-16 stable would I burn my house down? These speakers are only 40 watt each so dont need much power. Just a bit
Dot have amp yet, just looking for suitable one but want to get old amp to match speakers And any I like are always 8 minimum
"an 8 ohm amp" is kind of a nebulous descriptor. Your amp will probably be fine driving a 6 ohm nominal speaker. The manufacturer has chosen not to rate it at 4 ohms. Usually that means that the amp would run hot under power testing or reach current limits that prevent generating the expected power into 4 ohm loads ( manufacturers don't rate into 6, rather they do 2 to 1 steps).
Adding resistors is messy in that it will mess up frequency response, and probably unnecessary to boot.
Use the amp and if you can play at the volume you want without it running overly hot, then all is fine.
David S
Adding resistors is messy in that it will mess up frequency response, and probably unnecessary to boot.
Use the amp and if you can play at the volume you want without it running overly hot, then all is fine.
David S
Any amp worth having will accept a total load per amp channel in the range of 4 ohms to 16 ohms. Some studio or PA/DJ amps will handle load down to 2 ohms, but I don't think we need to consider those.
As has been pointed out, there is no such thing as an 8 ohm Amp, there are only amps whose power has been rated at 8 ohms, so that all amps are rated the same. It is part of a rating standard. So, when you compare the power of one amp, you know it is comparable to another amp.
Also, a speaker impedance rating is nominal. Think of it as an average. Typically the speaker impedance of, as an example, an 8 ohm speaker will range from about 6 ohms up to about 50 ohms. The peak being at the resonance frequency of the speaker. Typically in the area of 30hz to 40hz.
So, again, not such thing as an 8 ohm amp. Only amps whose power has been rated to an standard that requires 8 ohms.
Most reasonable amps will handle any load in the range of 4 ohms to 16 ohms, that again is not a specification standard, but is standard, as in common, with most amps.
So, I don't really think you need to worry about this too much. Unless you are buying an incredibly cheap amp, it should be OK.
Steve/bluewizard
So, when
As has been pointed out, there is no such thing as an 8 ohm Amp, there are only amps whose power has been rated at 8 ohms, so that all amps are rated the same. It is part of a rating standard. So, when you compare the power of one amp, you know it is comparable to another amp.
Also, a speaker impedance rating is nominal. Think of it as an average. Typically the speaker impedance of, as an example, an 8 ohm speaker will range from about 6 ohms up to about 50 ohms. The peak being at the resonance frequency of the speaker. Typically in the area of 30hz to 40hz.
So, again, not such thing as an 8 ohm amp. Only amps whose power has been rated to an standard that requires 8 ohms.
Most reasonable amps will handle any load in the range of 4 ohms to 16 ohms, that again is not a specification standard, but is standard, as in common, with most amps.
So, I don't really think you need to worry about this too much. Unless you are buying an incredibly cheap amp, it should be OK.
Steve/bluewizard
So, when
How do you not agree with me, and how does your post reflect that? In summary, you said he needs a 4 ohm capable amp. I said most quality, even consumer, amps will handle loads in the range of 4 ohms to 16 ohms. How is that a conflict?
There is no such thing as an 8 ohm amp. All quality HiFi amps have the power rated at 8 ohms as part of a legal standard for HiFi amp power ratings. In the USA, the FTC (Federal Trade Commission) sets these standards. But that by no means means they are limited to 8 ohms. The standard range is a functional 4 ohms to 8 ohms nominal.
For what it is worth.
Steve/bluewizard
so called 8 ohm speakers are not 8ohms at all frequencies.....
it starts as 6 ohms at dc and can range in the 300's at other frequencies...
besides amplifiers have much lower output impedance than 8 or 4 or even 2 ohms...
SS amps have output impedances in the sub-ohm range,
tube amps can have taps for 16, 8 or 4 ohm speakers...
so what is there to argue about?
it starts as 6 ohms at dc and can range in the 300's at other frequencies...
besides amplifiers have much lower output impedance than 8 or 4 or even 2 ohms...
SS amps have output impedances in the sub-ohm range,
tube amps can have taps for 16, 8 or 4 ohm speakers...
so what is there to argue about?
There is nothing to argue about. But there is something to discuss and a question to be answered.
I feel that question has been answer from a couple of perspectives.
I think the ultimate answer is - don't worry about it, it will be fine.
Steve/bluewizard
I feel that question has been answer from a couple of perspectives.
I think the ultimate answer is - don't worry about it, it will be fine.
Steve/bluewizard
A 4ohms capable amplifier is NOT the same as an 8ohms capable amplifier.
No argument, just fact !
No argument, just fact !
yes, newbies worry needlessly about a lot of things that are non-issues...
and that worry stems from the fact that they think that their equipment may get damaged....
i see this type of attitudes not only in this board but also in a lot of other boards...
Don't you mean to say that - An 8 ohm capable amplifier is NOT the same as a 4 ohm capable amplifier?
If an amp is 4 ohm capable then it is 8 ohm capable, however, an amp that is 8 ohm capable is not necessarily 4 ohm capable.
However most amps, even common consumer amps, are typically 4 ohm capable. The Yamaha amps and Receivers, which I think anyone would consider consumer grade amps, are 4 ohm capable, and easily so.
I ran a Yamaha RX-797 Stereo amp with one 8 ohm speaker plus one 6 ohm speaker per channel and it was fine until one night it shut down during "Lord of the Rings". Though I admit I had the volume control up approaching 1 o'clock on the dial.
However, not all amps are 4 ohm capable. Sony AV Receivers being one example. They won't tolerate loads per amp channel below 6 ohms. But that is far more rare than common.
But in the context of this discussion, as long as the OP is only putting ONE speaker on each amp channel, it doesn't matter that much what he calls the speaker system. A vast majority of amp can handle a range of speaker loads from 4 ohms up to 16 ohms. Below 4 ohms, the current demand gets too high, and above 16 ohms, the amp becomes unstable. So, the working range for a vast majority of amps, especially common consumer amps is from 4 ohms to 16 ohms. As long as you are in that range you are fine.
A lot of people get confused about 8 ohm amps, it come up in every forum. But the answer is, there are no 8 ohms amps, only amps whose power has been rated according to the FTC standard ... which is 8 ohms. It by no means means the amp is limited to 8 ohms.
Other amps, not rated at 8 ohms, are typically attempts by the manufacturer to inflate the apparent power rating. The FTC is currently working on a Standard for AV Surround amps, which will likely require them all to rate their power at 8 ohms. The underlying controversy, is how many channels will need to be driven for that power rating? I say THREE, some say ALL, some say TWO. We'll see what the final standard is.
Just rambling a bit.
Steve/bluewizard
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I appreciate all the help here guys, didn't want to cause an argument though! But I must point out I am not totally incapable. I understand about claimed 8 ohm amps etc and that at low volume would be fine. My question was can I change the speaker to increase
Chance of no problems, which I have been told is not going to be an issue,
But I knew that anyway. Just wanted to know if could be done, and was informed by speaker dave that would interfere with other things, I am not a total
Newbie, I'm just not an expert in this field.
Chance of no problems, which I have been told is not going to be an issue,
But I knew that anyway. Just wanted to know if could be done, and was informed by speaker dave that would interfere with other things, I am not a total
Newbie, I'm just not an expert in this field.
What I and others have said it that - there is no problem.
An typical 8 ohm rated amp will handle speakers in the range of 4 ohms to 16 ohms, 6 ohms falls comfortably in that range so - no problem. No risk. No danger to that amp or speaker.
Any attempt to raise the impedance of the speaker is simply going to waste power to no good end. Yes, it can be done. But why? Even a limited amp should still be comfortably able to handle 6 ohms.
The only time this could be a problem is when you put another speaker on the same amp channel as the 6 ohm speaker. But with the right amp, even that is only a limited problem. I used an 8 ohm speaker pair combined with a 6 ohms speaker pair on a common consumer grade Yamaha amp, and it worked fine until I brought the volume up too loud. For music at normal modest listening levels, it worked fine. I'm not recommending you do this, just pointing out that amps are reasonably tolerant of their load. (8 ohms plus 6 ohms = nominal 3.4 ohms)
A 6 ohm speaker on any standard reasonable amp is never going to be a problem.
You can raise the impedance with a resistor, but it wastes power, and is not necessary. The power of that resistor would have to be high enough to sustain its share of power. So, a 2 ohm in series with 6 ohms means the 2 ohm resistor gets 1/4th the total power. If you have a 100w amp, then the 2 ohm resistor will get 25w of power maximum.
So, yes it can be done, but it is unnecessary.
You originally said -
"...a pair of 6 ohm speakers and a 8 ohm amp, I understand shouldn't be used together..."
That is just a false statement. As has been explained, with a few extremely rare exceptions, there is no such thing as a 8 ohm amp. HiFi Amps, by a legal standard, all have their power rated at 8 ohms so you can fairly compare them. But that by no means means they are "8 ohm amps".
It should be noted that AV amps, Boomboxes, Mini/Micro systems are not classified as HiFi, consequently they do not have to rate their power according to the FTC standard. Which is why you see many of them with power rated at 6 ohms or 4 ohms. That is simply to inflate the apparent power and fool the consumer.
Now AV amp are HiFi quality, however the FTC has not completed the standard by which AV amp/receivers will be rated. But likely when the standard, which they are working on, is complete, it will be rated to an 8 ohm load with multiple channels driven. The current delay is in determining what constitutes a fair number of channels to be driven for a fair power rating.
So, yes you can increase the impedance. But it is absolutely unnecessary.
Steve/bluewizard
An typical 8 ohm rated amp will handle speakers in the range of 4 ohms to 16 ohms, 6 ohms falls comfortably in that range so - no problem. No risk. No danger to that amp or speaker.
Any attempt to raise the impedance of the speaker is simply going to waste power to no good end. Yes, it can be done. But why? Even a limited amp should still be comfortably able to handle 6 ohms.
The only time this could be a problem is when you put another speaker on the same amp channel as the 6 ohm speaker. But with the right amp, even that is only a limited problem. I used an 8 ohm speaker pair combined with a 6 ohms speaker pair on a common consumer grade Yamaha amp, and it worked fine until I brought the volume up too loud. For music at normal modest listening levels, it worked fine. I'm not recommending you do this, just pointing out that amps are reasonably tolerant of their load. (8 ohms plus 6 ohms = nominal 3.4 ohms)
A 6 ohm speaker on any standard reasonable amp is never going to be a problem.
You can raise the impedance with a resistor, but it wastes power, and is not necessary. The power of that resistor would have to be high enough to sustain its share of power. So, a 2 ohm in series with 6 ohms means the 2 ohm resistor gets 1/4th the total power. If you have a 100w amp, then the 2 ohm resistor will get 25w of power maximum.
So, yes it can be done, but it is unnecessary.
You originally said -
"...a pair of 6 ohm speakers and a 8 ohm amp, I understand shouldn't be used together..."
That is just a false statement. As has been explained, with a few extremely rare exceptions, there is no such thing as a 8 ohm amp. HiFi Amps, by a legal standard, all have their power rated at 8 ohms so you can fairly compare them. But that by no means means they are "8 ohm amps".
It should be noted that AV amps, Boomboxes, Mini/Micro systems are not classified as HiFi, consequently they do not have to rate their power according to the FTC standard. Which is why you see many of them with power rated at 6 ohms or 4 ohms. That is simply to inflate the apparent power and fool the consumer.
Now AV amp are HiFi quality, however the FTC has not completed the standard by which AV amp/receivers will be rated. But likely when the standard, which they are working on, is complete, it will be rated to an 8 ohm load with multiple channels driven. The current delay is in determining what constitutes a fair number of channels to be driven for a fair power rating.
So, yes you can increase the impedance. But it is absolutely unnecessary.
Steve/bluewizard
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I am wondering if there is some confusion here. H Burch has an 8Ω amp meaning that when driving it hard you shouldn't run it at less than 8Ω nominal impedance for fear of overheating. This isn't about the power rating, it's about protection.
H Burch, in post #6, speaker dave outlined it in easy to grasp terms. If you don't run it hard, then an 8Ω amp should be ok under a 6Ω nominal load. Chances are it has thermal protection so it will shut off if it heats up.
H Burch, in post #6, speaker dave outlined it in easy to grasp terms. If you don't run it hard, then an 8Ω amp should be ok under a 6Ω nominal load. Chances are it has thermal protection so it will shut off if it heats up.
OK, specifically what is the brand and model of the amp?
An exclusively 8 ohm amp is nearly as rare as hen's teeth. I'd like to know what it is, because I doubt that it is truly an exclusively 8 ohm amp.
In post #5 he said -
"Don't have amp yet, just looking for suitable one but want to get old amp to match speakers And any I like are always 8 minimum."
I'd like to know where he is shopping where he is only finding exclusively 8 ohm amps? That is the part I doubt, unless he is shopping for extremely rare amps.
Which is why I repeated referred to common and reasonable amps.
Let him give us some examples of these exclusively 8 ohm amps, and I'll bet dollars to donuts that they are NOT exclusively 8 ohm amps. In fact, I'll bet dollars to donuts that any member of the groups can not find a purely 8 ohm amp that is affordable and readily available. Yes, someone might be able to find some obscure amp somewhere, but not an affordable or available amp.
It also won't hurt if he gave us his budget?
This question comes up in every forum I've ever been on, and it is always some mistaking the power rating at 8 ohm for an absolute statement that the amp is an 8 ohm amp.
So, if H Burch or anyone can give me an example of an exclusively 8 ohm amp that his not some rare obscure amp, I'll amend both my statements and my attitude.
Without a clear statement, giving the brand and model, we have to make assumptions, so is it better to assume common consumer amps, or to assume rare (to non-existent) obscure amps?
I doubt you can find an amp limited to 8 ohms, and if you did find it, barring a few extremely rare exceptions, why would you want it, when there are many affordable consumer amps that don't have that limitation?
Hey ... I'm just saying...
Steve/bluewizard
An exclusively 8 ohm amp is nearly as rare as hen's teeth. I'd like to know what it is, because I doubt that it is truly an exclusively 8 ohm amp.
In post #5 he said -
"Don't have amp yet, just looking for suitable one but want to get old amp to match speakers And any I like are always 8 minimum."
I'd like to know where he is shopping where he is only finding exclusively 8 ohm amps? That is the part I doubt, unless he is shopping for extremely rare amps.
Which is why I repeated referred to common and reasonable amps.
Let him give us some examples of these exclusively 8 ohm amps, and I'll bet dollars to donuts that they are NOT exclusively 8 ohm amps. In fact, I'll bet dollars to donuts that any member of the groups can not find a purely 8 ohm amp that is affordable and readily available. Yes, someone might be able to find some obscure amp somewhere, but not an affordable or available amp.
It also won't hurt if he gave us his budget?
This question comes up in every forum I've ever been on, and it is always some mistaking the power rating at 8 ohm for an absolute statement that the amp is an 8 ohm amp.
So, if H Burch or anyone can give me an example of an exclusively 8 ohm amp that his not some rare obscure amp, I'll amend both my statements and my attitude.
Without a clear statement, giving the brand and model, we have to make assumptions, so is it better to assume common consumer amps, or to assume rare (to non-existent) obscure amps?
I doubt you can find an amp limited to 8 ohms, and if you did find it, barring a few extremely rare exceptions, why would you want it, when there are many affordable consumer amps that don't have that limitation?
Hey ... I'm just saying...
Steve/bluewizard
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