Amp for 4 Ohm Speakers

[AcuDefTechGuy]

Really? Gonna need to get the mods to deduct some of that rep.

If connecting 4 ohm speakers on the 8 ohm connection gets 210 watts, but generates more heat than the amp can dissipate and is bad for it, then what's the point of bragging about it?

If you connect your 4 ohms speakers to the CORRECT 4 ohm connections like you are SUPPOSE TO, do you still get the "double-down"?

 

[zumbo]

I wouldn't call that a good thing...

Connecting 4ohm speakers to any amp is never a "good thing". The negatives out-weigh the positives. However, many great sounding speakers are 4ohm. So, the rewards can be fantastic. It's just tough on the amp, which is why having the option to make a proper connection is a fantastic thing.

 

[AcuDefTechGuy]

I wouldn't call that a good thing...

Exactly.

Oh boy, sure I can double and quadruple my power outputs, but my amps may explode.

 

[zumbo]

If connecting 4 ohm speakers on the 8 ohm connection gets 210 watts, but generates more heat than the amp can dissipate and is bad for it, then what's the point of bragging about it?

This is the fact of any amp, and I am not bragging. I didn't even bring McIntosh up in the thread.

Again, I recommended DENON POA 6600.

If you connect your 4 ohms speakers to the CORRECT 4 ohm connections like you are SUPPOSE TO, do you still get the "double-down"?

No. As they say, you get the power you paid for.

 

[zumbo]

Exactly.

Oh boy, sure I can double and quadruple my power outputs, but my amps may explode.

Your ATI 3000 series amps will do 300W@8ohm, and 450W@4ohm.(full bandwidth)

With 4ohm speakers connected, the amp will produce more heat. And, it will have all of the other negative aspects of an amp asked to drive a less resistive load.

What it doesn't do is double down for 600W.

It also doesn't give you the option to use 4ohm speakers while maintaining it's 8ohm specs.

It's really not as big of a deal as you guys are making it.

 

[its phillip]

Your ATI 3000 series amps will do 300W@8ohm, and 450W@4ohm.(full bandwidth)

With 4ohm speakers connected, the amp will produce more heat. And, it will have all of the other negative aspects of an amp asked to drive a less resistive load.

What it doesn't do is double down for 600W.

It's really not as big of a deal as you guys are making it.

Yes, the amp will produce more heat, but not more than the amp can dissipate. Key words.

If you are supposed to use 4ohm connections on that mac to get 105W, then that's what you should do. You shouldn't say it "doubles down" if you are using the amp incorrectly and generating more heat than the amp can dissipate.

With that being said, the Denon amp is a good recommendation.

 

[AcuDefTechGuy]

Your ATI 3000 series amps will do 300W@8ohm, and 450W@4ohm.(full bandwidth)

With 4ohm speakers connected, the amp will produce more heat. And, it will have all of the other negative aspects of an amp asked to drive a less resistive load.

What it doesn't do is double down for 600W.

It's really not as big of a deal as you guys are making it.

We're just talking.

So are there actual published measurements that say this McIntosh amp actually double-down if you connect 4ohm speakers to 8ohm connections?

Or was this a speculation?

 

[zumbo]

Just wanted to add that I am not knocking the ATI amps, just stating facts of each.

 

[zumbo]

We're just talking.

So are there actual published measurements that say this McIntosh amp actually double-down if you connect 4ohm speakers to 8ohm connections?

Or was this a speculation?

It was the reply from McIntosh directly.

 

[zumbo]

Yes, the amp will produce more heat, but not more than the amp can dissipate. Key words.

If you are supposed to use 4ohm connections on that mac to get 105W, then that's what you should do. You shouldn't say it "doubles down" if you are using the amp incorrectly and generating more heat than the amp can dissipate.

Any amp maker is going to inform the customer to make the proper connection. Heck man, that's why they designed the amps the way they did.

As mentioned previously in other words, a McIntosh customer is going to buy the amp that is proper for the application. They are not the type of customer that will be buying an amp to apply to a cheater application, such as using the double down attempt.

In my current HT, I cheat. My 5-channel Adcom 7605 is giving me 175WPC@4ohm. It gets hot. Sometimes, it shuts down.

In my current 2-channel rig, I cheat. My 2-channel Denon 2200s produce 300WPC@4ohm. I use one per speaker giving me an available 600WPC@4ohm to each speaker.

A proper superior option of equal power for my 2-channel rig would be two McIntosh MC601's. That would allow me 600W per speaker@4ohm, while remaining within it's specifications.
http://www.mcintoshlabs.com/us/Products/pages/ProductDetails.aspx?CatId=Amplifiers&ProductId=MC601

 

[AcuDefTechGuy]

So anyway, the OP was trying to decide between the MAC and the ATI:

MAC: 4 ohm speakers on the 8 ohm connection gets 210 watts, but generates more heat than the amp can dissipate.

ATI (AT2002): 4 ohm speakers on this amp gets 300 watts (20Hz-20kHz, RMS), and the amp generates more heat than with 8 ohm speakers, but the amp CAN DISSIPATE the heat just fine.

 

[zumbo]

So anyway, the OP was trying to decide between the MAC and the ATI:

MAC: 4 ohm speakers on the 8 ohm connection gets 210 watts, but generates more heat than the amp can dissipate.

ATI (AT2002): 4 ohm speakers on this amp gets 300 watts (20Hz-20kHz, RMS), and the amp generates more heat than with 8 ohm speakers, but the amp CAN DISSIPATE the heat just fine.

Never debated any of that. Just been stating facts of the McIntosh amp in question.

Never intended for you to think I was suggesting the McIntosh amp in question was a better choice for this application.

It was the amp the OP mentioned, and I was just stating facts. Also, correcting wrong assumptions of how a McIntosh amp performs. In general, not just the one in question.

On a side note, the ATI will get hotter with 4ohm speakers connected, compared to 8ohm. It will become more distorted. It will clip sooner. And, all of the other aspects of using a cheater application.

 

[zumbo]

The reply from McIntosh is the expected reply. I can assure you their amps will perform as good, or better than others operating a less resistive load. The fact that the amp will double down is a clear indicator of it's superior design, compared to other amps.

If I had to warranty your car, I would certainly recommend you not drag race it. I would also recommend you use it in the manner it was designed.

 

[zumbo]

If you were to email Yamaha with the question of whether to use their speaker ohm settings within the receiver, they would inform you to do so.

They would also recommend not to use 4ohm speakers.

I used 4ohm speakers on my Yamaha receiver set to 8ohms without any problems.

As mentioned by someone earlier, it's all about liability.

 

[zumbo]

Recommending Denon POA 6600 for a second time. Don't wait!

These are superior amps, and the price is stunning.

Please understand this is two monoblock amps that will produce 450W@4ohm. Each.

http://www.audiogon.com/cgi-bin/cls.pl?ampstran&1309391249&/Denon-POA-6600A-Monoblocks

 

[zumbo]

And now nothing?

No, "thanks for the correction."

No, "I was wrong."

No, "glad you informed me of how an amp works!"

 

[PENG]

Any time you reduce the ohm load, an amp intern becomes more distorted.

Any amp.

Shocked you posted such a reply.

McIntosh is giving you the ability to connect a low ohm speaker without adding stress, distortion, or any other negative reaction an amp may have to such a load.

Zumbo, not trying to brag either, but I do know electrical theory, and I quoted directly from Mc manual. You have to understand how their autoformer work. It is just not the same design as others who don't use such technique. Please also check out their distortion curves. Yes they all distorted at higher output but we are talking in relative terms.

 

[PENG]

I honestly can't believe I had to send that email.

That's one reason why I respect people like you, black and white, facts based, never give up until getting to the bottom.

 

[PENG]

Just as any other 105WPC amp. However, it does double down. That puts it in the top tier amp category.

While it may be called "Auto", there is nothing auto about having to manually move the +.

As mentioned, I would love to have a proper McIntosh to power my 4ohm Quarts. The ability to connect 4ohm speakers without all the negatives that come with it is fantastic.

On a side note, 105WPC would not be the spec of choice for me. Just stating facts of the amp in question.

Autotransformer in electrical term has nothing to do with being "automatic". An autotransformer is simply a one winding transformer without multiple taps to change the output voltage.

Of course it will try to double down, that's simply Ohm's law but the fact that it use an autotransformer to change the voltage, it will not have the same efficiency as OTL designs, hence more heat and not good to do so as per Mc's email to Zumbo. It also has lower damping factor.

 

[3db]

And now nothing?

No, "thanks for the correction."

No, "I was wrong."

No, "glad you informed me of how an amp works!"

Are you forgetting to floss?