Amp Killers!

[Bahamayellow]

I don't see how the Kappa 9 or any Quantum could be in a "hall of shame".

Don't buy the speaker if you don't have the amp.

There are some Carvers that work very well with Infinity's.

I posted this in the speaker section of show us videos of ur systems. I think I am one of the few if any Infinty speaker system videos shown. My K9s were bought from the original owner and has not been touch internally except for the woofer refoam. I am running 2 Carver Tfm-25s (250 watts a channel) . One was fully rebuilt by Rolland at high tech audio and he did wonders with it. The dynamics and midrange outshines the stock one. I don't like lugging heavy amps around and these are small at 30 pounds each. I am a also running the bass switch in normal mode as its plenty for me. It has a parasound zpre and a 20 year old onkyo DVD player. It's a odd selection of jazz but I think it goes through the range of the K9s.

 

[okeeteekid]

I saw some white smoke coming from your amp Lol, just kidding, I played your video through my k9's and it sounded pretty awesome, nice video and system you have.

 

[Bahamayellow]

I saw some white smoke coming from your amp Lol, just kidding, I played your video through my k9's and it sounded pretty awesome, nice video and system you have.

Haha thanks okee. I think it was u that said know your limits on your amp. I know mine are not power house amps like macs or Krell and I don't run them like they are. I don't want to damage equipment.or the speakers especially because I like them too much. Lol. Not sure how carver designed his amps but they only get Luke warm no matter how hard I drive them.

 

[stevo137]

Excellent!

Thanks for sharing.

Great speakers and amps!

 

[chef free]

I don't see how the Kappa 9 or any Quantum could be in a "hall of shame".
.

I mean shame for the amps that can't handle it!

If the speaker impedance was rated reasonably as per IEC, i.e. min impedance not less than 80% of nominal, I'd agree. Then, people would be able to more clearly understand if they wanted buy a speaker with that characteristic, nominal impedance rating of 1.1 ohms, or that they needed a particular sort of amp to run them. The 4 to 6 ohm nominal rating they have is absurd. But, I suspect sales would have been impacted with a more realistic impedance rating.

Good point, I suspect Arnie was shooting for those low frequency specs...

Some folks say the RS II are power/current hungry.
They do drop down to just barely over 2 ohms for part of the musical spectrum.

So an amp killer speaker is a combination of low impedance and low efficiency? Makes sense, and the QLS-1 with its 1 ohm dips and low efficiency 82 db 1w/1m, certainly qualifies!

 

[Bob]

you guys are funny. infinity speakers command LARGE high powered amps. they are played
LOUD with LOUD music (no elevator music allowed).

its a real-life test lab for weakest (audio) link - your amp.

it's almost like buying a Corvette and complaining about speeding tickets when you were only
in 3rd gear, or flipping it around a curve (banked for 30) at 95mph.

 

[goodolpg]

chef free, I'm just going by comments made here after I bought a pair of RSII's, AK'ers mentioned they can be a difficult load.
And also one Canadian magazine review.
Thankfully I had just made the change to separates maybe a couple years before that (after 35+ years using only receivers) so I had enough safe power to run them.

 

[goodolpg]

you guys are funny. infinity speakers command LARGE high powered amps. they are played
LOUD with LOUD music (no elevator music allowed).

its a real-life test lab for weakest (audio) link - your amp.

it's almost like buying a Corvette and complaining about speeding tickets when you were only
in 3rd gear, or flipping it around a curve (banked for 30) at 95mph.

If nothing else, maybe this thread will serve as a guide/warning for uninformed people* who have or are considering buying some classic Infinity "amp killers".

*As mentioned, even with 40 years of stereos I did not know the RS II's I bought were a hard load to drive until after I bought them.
And there's lots of people out there with less experience than I had.

 

[stereofanboy]

RS IIs didn't kill my AU-919 but they did put it in protection.

 

[Pio1980]

RS IIs didn't kill my AU-919 but they did put it in protection.

At an undisclosed location under a new name?
Sorry, low hanging fruit.

 

[Bob]

here's something: my haflers drive Polk7Bs. there are fuses on both sides.

maybe add a set of fuses at either end and start with 1amp (that's about 8w) then crank it UP,
til the fuse blows, then up the fuse amperage, maybe stop at 100amps (that's about 800 watts),
or liquid-cool the amp output stages like the PC-gamers. use car fuses - cheaper that way.

or have a heat monitor probe on the driver & output stages with auto-squirts of freeze spray aimed at it.
move up to liquid nitrogen if you're doing a neighborhood concert of Grateful Dead music.

I limit my tinnitus gear to about 90db. In my days of youth I went to two concerts - I was deaf for
a week and the ringing lasted two. they were free, too. Central Park. when I didn't hate NYC.

nowadays it would take major set of drugs for me to listen to loudness.

 

[whoaru99]

you guys are funny. infinity speakers command LARGE high powered amps. they are played
LOUD with LOUD music (no elevator music allowed).

its a real-life test lab for weakest (audio) link - your amp.

it's almost like buying a Corvette and complaining about speeding tickets when you were only
in 3rd gear, or flipping it around a curve (banked for 30) at 95mph.

LOL. While I don't have any of these speakers I have several amps that would run them just fine so there is no whining/complaining here. Simply stating facts about a pretty lame impedance rating on those speakers.

Heck, one pair of amps I have is rated for 1300 watts each, continuous, into 1 ohm load. Probably light those Kappas on fire if I really wanted to.

 

[Mark B]

The graph below posted by AK'er 240 Volts in the thread Why 4 Ohm Loads Stress Your Amplifier is an excellent illustration of how much greater transistor dissipation (heat) is at 4 ohms vs 8 ohms for a typical class AB amplifier. You don't need to crank the volume to stress an amp that isn't designed to handle low impedance.

 

[whoaru99]

Yeah, certainly lower impedance increases load.

Personally, the few examples of "amp killer" speakers aside, I think the risk is greatly exaggerated in general.

 

[Kev_rat]

View attachment 1010609 No one mention the RS4.5. No experience with them but pretty sure these would be a pretty tough load.

I don't think he RS-4.5 would be in the amp killer territory.
I have run mine on a number of Amps over the years with no problems as long as the amp is happy dealing with a bit below 4-ohm
It is probably getting moot these days as there can't be many intact ones left - there was not many to start and it seems that every month or so someone is selling drivers from parted out RS-4.5s

 

[Pio1980]

Rod Elliott has some comments on his site attributing much of this to the passive crossovers on the drivers in such speakers.

 

[7.62]

I sure wish I was closer to okeetee and bahama, I’d supply the frosty beverages for a listen .

Nice you guys !

I tried posting a video with the rens but It doesn’t work for me ., I did manage to get one up in the Speaker forum.

 

[jazzmans]

The graph below posted by AK'er 240 Volts in the thread Why 4 Ohm Loads Stress Your Amplifier is an excellent illustration of how much greater transistor dissipation (heat) is at 4 ohms vs 8 ohms. You don't need to crank the volume to stress an amp that isn't designed to handle low impedance.

View attachment 1011457

Except in class A operation, since the transistor (or tube) is always seeing full power, having it being 'used' instead of having to be disappated via the heatsinks causes the amps to run cooler apparently.

 

[okeeteekid]

I sure wish I was closer to okeetee and bahama, I’d supply the frosty beverages for a listen .

Nice you guys !

I tried posting a video with the rens but It doesn’t work for me .

If your video is on youtube copy and past the link here, that's what I do.

Except in class A operation, since the transistor (or tube) is always seeing full power, having it being 'used' instead of having to be disappated via the heatsinks causes the amps to run cooler apparently.

That might be true Jazz but I'm still weary of using my Forte 4a to drive my k 9's anytime soon, I like my 4a so much I wouldn't want it to suffer any damage from the mighty K 9's LOL

 

[432HzBob]

My little 4 0hm RS6-B's 1st killed a Pioneer SX-626, then a SX-828 and finally my SX-950.
They also killed a Luxman R-106 which is granted, not a super speaker driving unit.
The only thing these haven't (yet) killed are a Luxman R-1120 and a Denon 1309R integrated.