Need some help with amp choice

[mark620]

I am going to be building a set of front speakers. I will be using either seas drives or scan speak. I am looking for a amp to run them. I am thinking 100-200 watts per channel. I will run the signal out of my Yamaha rec. Do I need a pre-amp? Are there good pre-amp/amp combos or all in one. I have a lot of car audio exp but the pre amp in the home audio end confuse me to if I need it. I am not looking for the best but a good performer and not trying to break the bank..Thanks
​

 

[lsiberian]

All you need is a good receiver unless you are building an active speaker. In which case you'll want a minidsp and some sort of amp.

 

[Pyrrho]

Isberian is right that all you need is a receiver. A receiver is a tuner, preamp, and power amp in one box. Now, if you have difficult to drive speakers, then you will want to use preamp outputs on the receiver (if it has them) and a separate power amp to drive the speakers. But for most people, a receiver is all that is ever needed to drive the speakers.

It is worth mentioning that whether a separate amplifier is needed or not has NOTHING to do with the quality of the speakers. It is only a question of whether the speakers are difficult to drive or not. In other words, it has to do with the electrical properties of the speakers, not how good they sound or anything else about them. I have over $6k worth of speakers hooked up to a surround receiver. My speakers are of normal impedance and of normal sensitivity, so a separate power amp would be a waste. On the other hand, I have a two channel system in which I use a separate power amp. That is because the speakers in it are 3 ohms.

 

[mark620]

My receiver does have pre-outs. I was under the impression that I would want to do a separate amp with more power than my 95w a channel to a set of high end fronts. A amp will give you a better , cleaner power than you receiver right. I under stand all he parameters I was looking for some direction as to needing a pre-amp. Since my rec. has pre-outs I need just a amp for more power than what my rec. has. I might consider bi-amping then I would need a 4 channel . Any input on some reasonable amps..

 

[Pyrrho]

My receiver does have pre-outs. I was under the impression that I would want to do a separate amp with more power than my 95w a channel to a set of high end fronts. A amp will give you a better , cleaner power than you receiver right. I under stand all he parameters I was looking for some direction as to needing a pre-amp. Since my rec. has pre-outs I need just a amp for more power than what my rec. has. I might consider bi-amping then I would need a 4 channel . Any input on some reasonable amps..

You have been misinformed. I run over $6k worth of speakers off of my home theater receiver. I do not use external amplifiers for my main speakers (just the subwoofers, which the receiver does not power). The reason is that my speakers are of normal impedance and sensitivity, and do not require additional power. With my main 2 channel system, I use a separate power amp. That is because they are 3 ohm speakers. The reason to use a separate amplifier is if one needs it for driving difficult speakers. The sound quality of them has nothing to do with it; it is purely a matter of their electrical properties.

If you want to effectively flush your money down the toilet, then buy a separate amplifier when you don't need it. And spend crazy amounts of money on cables, too, if you have more money that you want to get rid of without improving your sound.

 

[slipperybidness]

My receiver does have pre-outs. I was under the impression that I would want to do a separate amp with more power than my 95w a channel to a set of high end fronts. A amp will give you a better , cleaner power than you receiver right. I under stand all he parameters I was looking for some direction as to needing a pre-amp. Since my rec. has pre-outs I need just a amp for more power than what my rec. has. I might consider bi-amping then I would need a 4 channel . Any input on some reasonable amps..

100w vs 95w isn't gonna get you anything extra. Double the watts = 3db increase.

 

[AcuDefTechGuy]

Good idea to have AVR that has pre-outs. You probably won't need external amps if you are like most of us (myself included). But you can always add an amp later if you are NOT like most of us.

 

[mark620]

I know not to waste money on speaker wire. I get all my cable from blue jean and I am very happy with there products. I guess my misconception is related to car audio. In a car audio head unit it could be 25x4 .But a amp that is 25x4 is a much better source of amplification .I was thinking a rec. vs a amp was kind of the same deal. Thanks for the info.

 

[Pyrrho]

I know not to waste money on speaker wire. I get all my cable from blue jean and I am very happy with there products. I guess my misconception is related to car audio. In a car audio head unit it could be 25x4 .But a amp that is 25x4 is a much better source of amplification .I was thinking a rec. vs a amp was kind of the same deal. Thanks for the info.

If we are talking about an honest 8 ohm speaker of normal sensitivity, then the receiver will be fine. If not, then you will need to look to the ratings for an impedance appropriate to the speaker. Typically, receivers are not good with very low impedances.

And with car audio, there are all sorts of nonsense claims about power that, for the most part, are no longer as much of an issue with home gear, since the government has put the force of law to work on the matter. They can still play some games, though, so you need to read the claims carefully, and if in doubt, look to professional reviews in which the product is measured.

 

[Goliath]

My receiver does have pre-outs. I was under the impression that I would want to do a separate amp with more power than my 95w a channel to a set of high end fronts.

If you listen in typical conditions the possibility is high that you will not use even a fraction of 95W under any circumstances.

Things change *if* you crave deafeningly loud SPL (105 dB+) in a large open-plan space and are seated far away (6-8 meters) and own speakers with a poor sensitivity (84 dB 1W/1M), with impedance dips below 3 ohms using music that is energetic at frequencies where your speakers dip to 3 ohms then, perhaps only then, you may need to consider a more suitable amp.

How much power (voltage multiplied by current) is drawn from a speaker has nothing to do with the size of the amplifier or how much power it can supply. It has more to do with your listening habits, your speaker sensitivity and the program content you listen to. A larger amp can merely supply more potential power in conditions that require it.

A amp will give you a better , cleaner power than you receiver right.

Perhaps, but amplifiers not operating at full power tend to operate at lower distortion along their power curve. Most people I know don't operate their AVR at full rated power. If the distortion is low enough it won't matter what source was responsible for supplying that power, whether it was an AVR or a McIntosh hyper-expensive integrated.

I under stand all he parameters I was looking for some direction as to needing a pre-amp. Since my rec. has pre-outs I need just a amp for more power than what my rec. has. I might consider bi-amping then I would need a 4 channel . Any input on some reasonable amps..

Bi-amping won't give you more power. Are you hearing audible distortion at the volumes you listen at? What prompted you to think that you needed to fork out cash on a bigger amp? In what way do you think it would benefit you?

 

[mark620]

I know bi-amping will not give me more power, its meant for more adjustability. I am going to be building set of 2 ways using seas or scan speak. In doing my research I found most set ups were using external amps.That's what led me to think a separate amp was the way to go. I come from the car audio world (not the boom boom ,but the SQ side) so I am so use to amping, and going active or bi-amping. I just do not want to spend a few weeks building a set of speakers and find out my rec. power is not what they really want. The drivers I want to use have good sensitivity and I want to be able to drive them to there potential. Maybe I am looking into it too much. That's what happens when you come from the $4000+ car stereo world..

 

[Pyrrho]

I know bi-amping will not give me more power, its meant for more adjustability. I am going to be building set of 2 ways using seas or scan speak. In doing my research I found most set ups were using external amps.That's what led me to think a separate amp was the way to go. I come from the car audio world (not the boom boom ,but the SQ side) so I am so use to amping, and going active or bi-amping. I just do not want to spend a few weeks building a set of speakers and find out my rec. power is not what they really want. The drivers I want to use have good sensitivity and I want to be able to drive them to there potential. Maybe I am looking into it too much. That's what happens when you come from the $4000+ car stereo world..

With car audio, the ratings on head units are typically inflated by giving you the power output with massive amounts of distortion, and likely not over the entire frequency spectrum. With home audio, typically (though not always) one sees ratings into low levels of distortion from 20-20kHz, and so those ratings can generally be trusted, into the rated impedances. One thing that upsets some people, though, is the fact that most surround receivers cannot deliver that power to all channels simultaneously, but that is not a real problem for reasons explained at:

The All Channels Driven Amplifier Test Controversy | Audioholics

The All Channels Driven (ACD) Amplifier Test | Audioholics


Now, of course, there are ways in which manufacturers can and do manipulate ratings:

AV Receiver and Amplifier Power Ratings Trends: How and Why Wattage Ratings are Manipulated | Audioholics

But it does not compare with the ridiculousness found in car audio.

When comparing power ratings, one should compare over the same set of frequencies, with the same impedance, with the same (or very similar) levels of distortion, both continuous ("peak" power is generally outrageous inflation of the numbers). Otherwise, the ratings simply cannot be directly compared at all, as they are not discussing the same thing at all. Unfortunately, the law does not require more honesty in such things than it does, but if one takes the precaution of not trusting a power rating if it it does not specify duration (should be continuous), impedance, frequency range, and distortion, and then only comparing the number with other numbers with the same stipulations (or, in the case of distortion, nearly the same), then one will be fine.


Edited to add:

Here is a link to a car stereo from a respectable brand (I use a Pioneer car stereo myself):

DEH-X9600BHS - NEW! - CD Receiver with Full-Dot LCD Display, MIXTRAX, Bluetooth®, HD Radio™ Tuner, and SiriusXM Ready | Pioneer Electronics USA

If you click on the specifications tab, and then on the audio tab, you will see that they claim 50 watts x 4. However, they do not there specify what frequencies are covered, what impedance of speaker, what level of distortion, or whether that is continuous or some sort of "peak" power, SO IT IS COMPLETELY USELESS AND WITHOUT REAL MEANING.

Here is the manual with the real specifications on page 33:

http://www.pioneerelectronics.com/StaticFiles/Manuals/Car/DEH-X9600BHS_OwnersManual080713.pdf


There we see that the 50 watts is peak. They rate it at 22 watts continuous. Into 4 ohms. But that is not all. It is rated from 50-15kHz. Meaning, if they rated it from 20-20kHz, all that you want, it would be a lower number. And then they say it is with 5% THD. That is higher distortion than you want to hear, so it is even less for a well rated amplifier. In other words, the difference between this and an amplifier rated at 50 watts RMS continuous into 4 ohms, 20-20kHz, with <0.1% THD is quite dramatic. That is because the "50" in each case is referring to a completely different thing (peak vs. continuous, limited frequency vs. full frequency, high distortion vs. low distortion).

I would guess (and I freely admit, this is a guess; to know, it would have to be measured) that the Pioneer head unit is really more like a 10 watt continuous per channel amplifier, if rated over the entire frequency spectrum and at a low level of distortion.

One more thing: Pioneer is not exceptional in this regard. It is standard practice for car stereo makers to give ridiculous ratings for head units. So I am not picking on Pioneer in this; they are a convenient example, selected by me, because I would recommend buying a Pioneer for a car stereo. If we were looking at a bad brand, it would not give us a good example of the ridiculousness of car stereo ratings, as one might think that the idea only applies to bad brands.

 

[mark620]

Tell me about it, car stereo companies are a joke. The top 3 bands all have there good units Pioneer pretty much leads the way. Amp wise class a/b is where its at with mosconi and audison leading the way. Class d imo does not sound as deep and colorful. You get what you pay for in car audio. I guess I understand that the home rec. are much better than I though power wise.

 

[lsiberian]

For diy audio I believe bi and tri amping is advantageous for better crossover design. I personally use chip amps and a minidsp for this purpose. I think in diy audio going active is a good option to have.

Sent from my SAMSUNG-SGH-I727 using Tapatalk