New Amp Questions

[adamd]

Let me start out by saying I am new to the separates market. This is my 1st purchase.

I purchased a Carver AV 505 5 channel amp rated at 80 watts per channel with all 5 channels driven into 8 ohms and 100 watts per channell with only 2 channells into 8 ohms. (these are still on sale at onecall.com for only $283 - originally $1500 - brand new with free 5 year warranty)

I am using my Harmon/Kardon AVR 20 II receiver as a pre amp (This piece is about 10 yrs old - not digital - and is rated at 45 watts per channell)

I have JBL Studio Series Bookshelf speakers (these are 3 way fairly large bookshelf spaekers)

I am only using 2 channels.

Will an amplifier really sound better after a 48 hour break in period(I currently have a CD on a continuos loop)?

I was not too impressed with the sound right out of the box and it did not get that much better as the amp warmed up over a few hours.

The sound I got previous with just my old receiver was almost just as good.

Any thoughts?

Thank you.

 

[zipper]

Some people say an amp will sound better after being "broken in". I can't say I've ever experienced that with a solid state receiver or amp,& I've never owned a tube amp. I find it very hard to believe that a 5x80wpc amp(especially a Carver) would ever retail for $1500, then sell for $283. I recently demo'ed a Carver & was skeptical of the design & power claims given it's size & lack of weight. You probably got what you paid for.
Stupid ? maybe,but you do have pre-outs on the H/K don't you? Reason I ask is,long ago,I had a friend hook his amp to the speaker outs on his receiver & couldn't understand why he had problems. Please don't take offense to the question.

 

[adamd]

No offense taken.

The Harmon/Kardon does have pre - outs.

 

[Mort Corey]

Have to agree with Zipper..."breaking in" something that is solid state just doesn't ring true.

Mort

 

[dmoss]

The Carver he bot is on sale at onecall.com. I think its for real. I would suspect that he either has a wiring problem or it could be possible he got a bad unit.

 

[av_phile]

The scant manual of the Acurus A250 and 200X3 I use to power a 5.1 set-up recommends a break-in period of about 250 hours to bring it to optimum performance.

There may be some debate on whether power filter caps charge faster after repeated use, thereby improving transient response, or that repeatedly heating the transister could bring it to optimum performance. I personally do not believe SS amps need break-in. But what the heck. Either 250 hours will break it in or I'd get accustomed to the sound Either way, I now am in love with it.

Going from a 45 watt/ch stereo receiver to a 100 watt/cha amp should yield some discernible difference in apparent volume. This is almost a 3db improvement. Same when I shifted from an Onkyo Integra 120 watt/ch receiver to the Acurus 250 watt/channel amp.

Offhand I should say that right out of the box, given the same volume setting you use for normal listening, the new amp should give an apparent increase in SPL (a doubling of power yields a 3db increase in volume, not SPL; an apparent doubling of SPL requires 6db increase or quadrupling of power)

But if your anticipated impression turns out underwhelming, there are variables to consider:

(1) Your amp may be starved of the needed electrical power from your AC mains. While your AC outlet may have been sufficient with your old receiver, the new amp may be more power hungry. The manual of my Acurus amps strongly recommends I connect them to dedicated AC outlets, with no other appliance sharing it. But that's because each amp consumes 1.2kva of electricity - about the same as a 1HP aircon. I don't know about Carver.

(2) Your speakers make have worked well with the old receiver but could be less enthusiastic with its new amp. It is sometimes not enough to match the two in terms of impedance and power handling. Consumer mass hi-fi equipment do not have this problem. But as you go up, the more exotic brands could be more choosy and sensitive. If not mistaken, Carver is in that league. HK is not. Speakers generally have unique capacitive and inductive reactances that some amps may be better handling than others. Then there is this damping factor in amps that may over-control speakers that already have sufficient internal damping to begin with, thus, yielding too tight a bass or weak bass.

(3) Last but not the least, consider matching the preamp with the amp. The reciever's preamp may be perfectly suited to drive its internal amp but not so when connected to an external amp. If the Carver needs 2 volts of input to drive it to full rated power, connecting it to a preamp whose output voltage is only 1 volt will drive the amp to only half its rated power at full volume. This may be the cause of your underwhelming impression of the Carver with the HK preamp. I wouldn't worry about the impedances. Most of them are within each other's range. Typically, preamps have output impedances of 22kohms, while amps have input impedances slightly higher up to 50kohms. Do refer to the manuals of your HK and Carver as they should indicate these voltages in RMS. If the disparity in voltage is great, then you have a problem - I would suggest you get a new preamp with the right output voltage.

 

[dsmith901]

Amps

As one who started out with a H/K AVR20II and added a Carver 705X I know what you mean. The Carver amp did not sound as good as the AVR20II receiver, which was probably the best of its generation BTW, with an excellent amp section. I later added a H/K PA5800 multichannel amp and while it did not sound better it did play much louder, especially in the rear speakers, and gave considerably more bass for my full range front speakers. There are better amps out there than the Carvers. You may want to look for a PA5800 or a H/k Signature 2.1, both of which are out of production but still available used. Also, the Marantz MM9000 (5 X 150 watts) is currently being discounted nicely by Accessories 4 Less (do a search). These are new units with a 3 year warranty, and is not that much more than the Carver.

 

[Ross]

"Breaking-in" an amp is a psuedo scientific concept. It sounds like a logical occurence, but in reality, does not exist. Yes, an amp may "Warm" up and get into the "Zone" for optimal performance, but a stated time lapse that will supposedly "break-in" the amp does not exist. That would be like saying the amp will continually "break-down", and over time constantly get worse and sound worse.

I don't see how the age of a solid-state amp will make it any better, its not a bottle of fine wine. If a solid-state amp "breaks-in" at any point in its ownership, then I'd suggest returning it to get your money back, and buy a unit that does not have such a defect. Warming the circuits up does occur and absolutely does affect the sound in a positive way, but "breaking-in" does not.

"or I'd get accustomed to the sound"

Yep.

best,

 

[hopjohn]

The amp section in most H/K's is very solid, and are ususally very conservatively rated. I doubt that there would be much of an improvement using the carver amp and from what your saying it sounds like I might be right.

 

[jimbob94005]

Harmon Kardon AVR 20 II

Do you happen to have a photo of the back of the unit showing the various inputs and outputs ? If so, I'd appreciate if you could please send me a copy.

Thanks, Jimbob

 

[adamd]

You're about a year and 3 amps late for this thread. Moved on to 2 channel Coda products.