Help with a 2 channel receiver

Re: Help with a 2 channel receiver

Sorry to respond to your questions with more questions, but why do you feel the speakers could definitely use more power, and what are you hoping to gain with more power? Whatever it is, going from a highly unreliable 100 watt rating to another highly unreliable 150 watt rating won't make any difference. Watt ratings in receivers and particularly in speakers actually mean very little. That is why I ask what your goal is.

That is from Amazon, and taking it as accurate, you don't need any more power.

Re: Help with a 2 channel receiver

If remote control isn't a must, you might look to ebay for a good, solid used one. Harman/Kardon made some great stuff in the 80s. The problem is there is always a risk.

Still, it is doubtful you will gain a noticeable bass, regardless of what power you add. It just doesn't have that big an influence, particularly as sensitive as those speakers are suppoeed to be. A good sub (a real sub) will do much more.

Re: Help with a 2 channel receiver

Pioneer made some truly awesome stuff back in the 70s. That is definitely a route to consider, but it can also be pretty expensive. I like the Harman/Kardon from the early/mid 80s. A few years ago I got a 590i on ebay for about $80. I think they had a more powerful model at the time as well. don't get too wrapped up in power ratings. The old receivers used plain old brute force where the new ones kind of use smoke annd mirrors to achieve power. A good old receiver will almost certainly reproduce at least as good if not better sound than a cheap new one.

Just to parse the numbers a bit. If your speakers actually have sensitivity of 98dB it basically means this. A more common sensitivity measurement is something like 88dB. Many speakers are lower than that. My main speakers are about 84dB. What that means is, due to the high sensitivity, your speakers with a 100 watt amp is essentially the same as a more standard speaker (88 dB) with a 1000 watt amp. That is why I doubt more power will have much effect, and no, I don't think it will have any noticeable improvement in bass.

Having said that, better electronics will always have some benefit, but it can be so subtle that you can't even hear it. If deep, powerful bass is what you are looking for, a good sub is almost always your best investment. My main speakers have are real-world flat down to 30 Hz and I power them with about 600 wpc, but I still use a good sub.

Re: Help with a 2 channel receiver

If these are the same E Series Cerwins that were on Cerwin-Vega's site until a year ago, that "8 ohm" impedance rating listed on other sites isn't exactly correct.

Because on CV's site it was written something to the effect of "8 ohm compatible"........which translates to giving the speaker wiggle room as far as that eight ohm rating is concerned. I believe this because many CV's over the years, particularly their larger models like this one have been rated at 4 ohms (when I used to sell them, we unfortunately had quite a few returns on them when they were used with lower-power receivers because the receiver would go into its protect mode at higher volume levels).

And while the manuals for many receivers warn about using speakers rated below say 6 ohms, based on many users' first-hand reports (including my own) they actually can handle many speakers like that.* But that warning spooks a lot of people so I'm not surprised to see more and more speaker companies revising the way in which they state their speakers' impedance ratings. FYI: if this specification paranoia doesn't make sense, check out the number of frivilous product lawsuits that are filed each year.

Anyhoo.....back to mhk87's specific problem: as far as bass is concerned with speakers with lower impedance ratings, it can be negatively affected with certain receivers. That's because many receivers include a built-in current limiting protection circuit that automatically cuts back on the amount of power going to such speakers. This is a compromise solution though: while the receiver will not shut down, something had to be sacrificed and that is bass response. And good solid bass requires lots of current - that is not an audio myth. There's a good reason large amplifiers use massive power transformers & such large heat sinks and/or cooling fans for their power amp's output transistors!

As far as gutsy stereo receivers that have real world 100 watt/channel ratings, these are the only ones I know of without doing additional research:

> Harmon/Kardon HK 3485 (IMO there are too many reliablity issues with H/K stuff, so personally I would choose something else)

> Denon DRA-697CI, a brute of a 2.0 receiver.

> Outlaw Audio RR2150

> Rotel also usually has one but I'm too lazy to look it up


* the impedance of a speaker isn't always all nice-n-stable i.e. depending on the design of the speaker it can pretty much stay at X ohms from 20Hz to 20kHz....but it can also (like with larger Infinitys sold back in the 80s) vary wildly and go from 6 ohms & quickly drop down to 2 ohms or even less during certain parts of a musical waveform (for the other speaker nerds out there: this is mostly due to crossover phase issues that help the speaker to generate loads of bass). Certain Advents, like the Smaller Advent I own myself, are rated at 4 ohms but in daily use they actually almost never get that low and pretty much hover around 5-6 ohms instead.

Re: Help with a 2 channel receiver

As far as power specs are concerned, you really have to read the fine print these days:

Here's the Denon's: 100W + 100W at 8ohms, 20Hz to 20kHz, .08%THD

That's a "real" 100 watts to me: a typical impedance rating (amps produce less power with higher ohms ratings); the full music frequency spectrum; totally inaudible total harmonic distortion.

Here's a $200 Pioneer's power rating: 110 watts x 2 (8 ohms, from 20Hz to 20kHz, 0.7% THD (I own several pieces of Pioneer gear, so am not singling them out).

The difference here is the THD rating - you still can't really hear the distortion, but now you're probably getting close to the amp's power generation limit and like with a car's upper speed limit, it can start getting rather unstable at that point. FYI: this doesn't perfectly apply to amps that use vacuum tubes, since these behave differently than solid-state electronics i.e. transistors.

Specs for really lightweight receivers (HTiBs are notorious for doing this) commonly state their power output starting at 40Hz instead of 20Hz and/or they only list a 1kHz frequency spec at their rated power instead of XXHz-XXkHz (reproducing a 20Hz note requires a lot more power than a 40Hz note). I mean really, who listens to 1kHz test tones on a regular basis?

FYI: power output specs are legal as long as the

* XXhz to XXkHz frequency spectrum
* % of THD
* impedance rating

......are all stated. This law was finally put into place sometime around 1977 as I recall because of all the complaints about wacky/misleading power claims being made up to that time by certain unscrupulous manufacturers.

Re: Help with a 2 channel receiver

I'm running a 1971 or so sony receiver (str 6055) rated at 30 or 40 watts depending on where i look. this thing has plenty of power to push my AR 2ax's (same vintage). This sounds GREAT. it is not what i would call nuetral or particularly detailed or even accurate, necessarily. but it is warm and open and i love the sound. you find this sony and many like it on ebay for $200 and under (some over too). models that start with 60 and 70 and end with 35, 45, 55 or 65 are all pretty good bets. there are plenty good models from pioneer, kenwood, marantz, sansui and more. there are deals to be had for sure. just so you know, a decent shop should be able to clean one up and make minor repairs for about $150-200.

the point is, these pieces can and do still sound great, in many cases better than the new stuff. my sony was both louder and cleaner sounding than my mid 90's onkyo integra a-9711, a heavy 80wpc integrated amp. i traded it in for my marantz avr.

buying from eby always comes with risks, but buying a 70's receiver can be a great purchase.

ps- lance, the model 6's are $99 right now at csw!!

Re: Help with a 2 channel receiver

i certainly wouldn't call myself an expert, but...

i did blow my sony when i first turned it on. it had been in storage and i, quite studiply, hooked up speakers and turned it on - with the volume cranked to the max. the lights came on i heard a pop, a brief hum and the lights went out. then i saw and smelled a wiff of smoke raise from the vents on top of the unit.

my point is two-fold, 1, like any legit piece of electrical equipment, these pieces are fused, i blew the fuse. 2, the fuse protects the rest of the electronics. once the fuse was replaced the unit sounded great.

now don't get me wrong, an amp, especially an older amp, can be overdriven without blowing the fuse (newer avrs + amps have protection circuits that turn them off before they come close to meltdown). but unless you are asking the amp to do something it was never intended to do, it will be fine, really. things it was not intended for include powering PA systems for walmarts, live metal concert sound levels, powering multiple pairs of low ohm speakers to unusually high volumes. oh and one other thing, powering your 3-way speakers to sound like you're running a large powered sub is not a good idea.

what it was intended for was powering even moderately efficient speakers to clean loud levels in spaces as large as a big living room with high ceilings, some units can do far more.

so 3 pieces of advice:
1- do not repeat my mistake, always turn the unit on with volume turned down.
2- if you can hear distortion the system is being over-driven and needs to be turned down. distortion can be caused by too much power or too little, and other causes as well. regardless of the cause, continued use can cause permanent damage to the speakers and or the amp - so turn it down. if you run into this problem frequently, you will need either more amp power or more speaker efficiency or both (unlikely).
3- have the unit inspected and tested when you first get it. if there is a decent repair shop around you, they should be able to do a clean up and basic inspection i'd guess for about $50 or less. of course if they find something wrong or need to strart replcing parts, the price will go up.

as far as cleaning units yourself, compressed air and dust-off are good. q-tips can be very useful as well. what you soak them in is another story and i won't advise here.

while the is certanly more to quality than weight, a 50 lb unit should have gobs of power. with older units you really can almost ignore the watt ratings and go by weight. ok, maybe not, but you should be pretty confident that power will not be a problem.

gotta run

good luck

Re: Help with a 2 channel receiver

It is a common misconception that large speakers are more difficult to drive. As a general rule, the opposite is true. Based on the specs of your speakers, the opposite is definitely true. I don't know how many times I will have to say that before you start believing it.

Re: Help with a 2 channel receiver

believe it...

and believe that the old stuff pushes a lot harder than anything new until you start doubling and quadrupling price ranges.

the best new amplification out there for the $$ IMO is the NAD C320 BEE from saturday audio for $300 closeout. you have to read the specs carefully. while this thing is rated at 50W, that's a real constant and conservative power rating. it will do 100W+ peaks no problem and it will deliver that power to inefficient power hungry speakers (which yours are not). just a thought if you're that worried about buying old or used.

Re: Help with a 2 channel receiver

I bought a fairly old Kenwood receiver on ebay but one channel pops off occasionally until I turn it up a bit. Is this a bad channel or something else? I cleaned the pot and there is no scratchiness.Help!

Re: Help with a 2 channel receiver

I think I've read something along those lines, it's old and it's good.