"High-current" amps for Arx speakers

[padgman1]

Jon, I've seen on some of your AVS posts that you highly recommend "high-current" amplifiers for quality speakers in general, and Arx speakers in particular. Can you expound on this further?

What qualifies as a "high-current" amp?

What does a "high-current" amp offer in terms of sound quality or dynamics that a lower current amp cannot?

Are there any name-brand AVR's out there that would come under the heading of a "high-current" amp, or is this mainly obtainable only with separate amplifiers?

[Chane M&C]

We recommend a simple standard for popularly-priced receivers and amplifiers. That characteristic is "high instantaneous current reserve" or something described more or less in those terms.

Since recorded content can be very dynamic, impressing them across a loudspeaker load intact depends on uncompressed peaks of amplifier current. All amplifiers have limits, but superior "drive" controls the moving speaker elements better as the complex signal changes almost instantaneously and across wide dynamic range.

Such an amplifier operates closer to a true current source, delivering power dynamically without restriction from speaker load fluctuation and changes in program material. This amplifier curtails current flow less either in the channel in question or into any other channel in the same amplifier.

Cheap receivers may sponge down a number of channels when any one of them is heavily stressed by current demand. This effect is both audible and measurable. On the other hand, an amplifier with good power supply regulation - the constant current concept - will not alter its current delivery as much or at all, making it sound more dynamic, musical, and less electronic.

(As an extreme example of this phenomenon, regulating the individual power supplies that source each stage of a tube amplifier so that they are unaffected by program content - tube amps are frequently misidentified as colored or distorted - is an acoustical revelation. A well-regulated tube amplifier is often considered the state of the art in amplification to this day, and has shocking transient performance and dynamic control. Some may even have reference-grade bass performance. The trick is plenty of power supply integrity.)

Amplifiers with this characteristic can be identified in the table of specifications by a significantly higher output wattage rating as the speaker impedance decreases. In other words, if the 8 ohm rating is 50 watts, a 4 ohm rating may be 100 watts. The ability to drive a 4 ohm load (or less) alone is a good indicator of an adequate output stage and power supply.

This characteristic translates into up to 3dB of headroom made available to the loudspeaker under the varying conditions of dynamic content. We get a firm "grip" from amplifier to speaker voice coils; The speaker sounds cleaner, fuller, more musical, and less electronic. Conventional amplifiers can sound thin, strained, and flat by comparison.

We can't comment on brands but searching the 8 ohm versus 4 ohm specification is easy enough to do.

[padgman1]

Thanks for the quick and informative reply, Jon.........

[Bandg]

I supplemented my modest AVR's power by running my L&R (A5's) using the pre outs and an Emotiva 2-channel amp. The sound is outstanding and is an improvement from using the AVR to run them. However, my AVR does not have the power rating of the mid to upper level ones. This has been suggested by others as a way to make up for the overstated power specs by some AVR makers. Hope this helps. Bradley

[padgman1]

Bradley,

I would love to do that, but the AVR I have does not have preouts...........:sad:

[jnordi]

That really limits you in that regard. You can spend a couple grand on a high end receiver capable of high current 8 Ohm vs 4 but for a lot less money you can go with a receiver with preouts and partner it up with a Emotiva XPA 3 , you have your front stage covered (LCR) with the 200 watt Emo and drive the other speakers with your reciever, this is concievable for about $1100 or less. I'm using an Onkyo 709 as a pre-pro, Emo XPA 3 and a an ATI amp (80 watts) but as Jon pointed out you have to look at the 8 vs 4 Ohm, the ATI doubles it power into a four ohm load. I have never used any of the the 709's amps, this setup new cost me around $1500. I hope this helps, by the way my LCRs are A5s and they shine with the XPA 3 which I think is the best bargain of the EMO amps.
Cheers Jeff

[padgman1]

Jeff,

I appreciate your thoughts ( on this as well as other topics in the TAI forums). At the time I decided to upgrade my music system from 20 year old Mitsubishi speakers and a 10 year old Panasonic receiver ( this time last year), I thought I made a reasonable decision by going with a mid-level Denon receiver with ~100w/ch x 7, knowing I was starting with a 2.0 system at first, then building to a possible 5.1 or 5.2 system in time. I first purchased a pair of the A1b's and was very happy - choosing them over a pair of the Ascend CBM-170's that I trialed at the same time.....Of course, desire for more set in, and to make a short story shorter, I now have a pair of the A5's ( thanks to aarons915!!) - still have the A1b's to ultimately use in that future 5. system. ( I also have a PSA XV15 sub).


Running the A5's on my Denon seems good for now, but I will probably need to upgrade the AVR to a model that has preouts and get another amp for the L/R A5's .......especially when the 5. system is complete ( and rear speakers mounted). I cannot justify the $1200-2000 expense right now.


Wish I knew then what I know now........

[jnordi]

Jeff,

I appreciate your thoughts ( on this as well as other topics in the TAI forums). At the time I decided to upgrade my music system from 20 year old Mitsubishi speakers and a 10 year old Panasonic receiver ( this time last year), I thought I made a reasonable decision by going with a mid-level Denon receiver with ~100w/ch x 7, knowing I was starting with a 2.0 system at first, then building to a possible 5.1 or 5.2 system in time. I first purchased a pair of the A1b's and was very happy - choosing them over a pair of the Ascend CBM-170's that I trialed at the same time.....Of course, desire for more set in, and to make a short story shorter, I now have a pair of the A5's ( thanks to aarons915!!) - still have the A1b's to ultimately use in that future 5. system. ( I also have a PSA XV15 sub).


Running the A5's on my Denon seems good for now, but I will probably need to upgrade the AVR to a model that has preouts and get another amp for the L/R A5's .......especially when the 5. system is complete ( and rear speakers mounted). I cannot justify the $1200-2000 expense right now.


Wish I knew then what I know now........

My man we've all been down that road, if only..........you should be fine for now with what you have, just don't try pushing the system to hard, I don't know you may be able to get some decent dBs of that setup, just push until you think the receivers straining, you could let that PSA XV15 blow the roof off if you want, that sub is a hidden gem, I had two of them and was amazed at the clean deep ouput, the XV15, A5s and A1s should have you rocking for a GOOD WHILE, don't concentrate on what you don't have, enjoy the excellent system you have, when funds become available we can talk so until then, ENJOY.
Cheers Jeff