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-   -   I'M GIVEN ER ALL SHE'S GOT CAPT'N, I NEED MORE POWER!!! (http://www.avsforum.com/forum/90-receivers-amps-processors/1514566-i-m-given-er-all-she-s-got-capt-n-i-need-more-power.html)

sandydankness 01-27-2014 09:01 PM

Title says it all, and i'm looking for amp suggestions.  I've got an Onkyo TX-NR828 avr.  It states it has 130 w/c at 8ohms 2 channels, so I figure i'm only getting 37w/c with all 7 speakers right now, right?.  Either way, it's not loud enough.  I bought it because it's got 9 or 11 preouts even though I run a 7.2 surround.  I'm thinking about a 5 channel amp somewhere around 150-200 w/c.  If I do that, I will have 2 channels left of the avr to push 130 w/c, right?

 

So, as long as I'm thinking right does anyone have a 5 channel amp suggestion?  Or maybe i'm wrong and need clarification, which would be usefull too.  Thanks,

 

Sandman


derrickdj1 01-27-2014 10:19 PM

A common answer on these forum is Emotiva. A less costly option is to look for a used amp. Acurus, B&K, Rotel and NAD are some good choices if you don't mind used gear. A lot of used gear is in mint condition. A good amp can last 30 years without problems. Sherbourn, Sunfire Grand and Parasound are also excellent choices.

astrallite 01-27-2014 10:25 PM

Firstly, you are incorrect about the Onkyo 828's power output. Per sound&vision (test here)

It says these speakers are capable of 80W x 7 at 8 ohms. Are you trying to drive 7+ speakers that are all 4 ohm nominal in a large room? Then you may need more power.

Although the Onkyo should not be your pre-amp since the pre-amp outs generally clip at 1Vrms on big box receivers like Onkyo, Yamaha, Denon, etc. You probably won't drive an external power amplifier much louder than the internal receiver amps with such low quality line level signals. If you have to use an AVR, use Marantz SR6xxx line and above models, as they can put out a 4+ Vrms (check the Audioholics and S&V reviews) which will blow up a power amp before the receiver's pre-amp even starts clipping. Alternatively you could use a pure pre-amp like Emotiva UMC-200, although I think a Marantz receiver is a more cost-effective bet.

Also if you really want noticeably more power, you can't just use any separates amp, to beat the Onkyos by more than a few db would need multiple XPA-2s or XPA-1s, getting something like a couple of UPA amplifiers is not going to cut it and would be effectively a sidegrade.

sandydankness 01-27-2014 11:51 PM

5-8 ohm speakers and 2-6ohm speakers plus 2 subs in a 2700ish cu. ft. room.  So are you saying it isn't cost effective to get an amp to increase volume? How much am I going to have to spend to get more db?

 

Sandman


arnyk 01-28-2014 03:02 AM

Quote:
Originally Posted by sandydankness View Post

Title says it all, and i'm looking for amp suggestions.  I've got an Onkyo TX-NR828 avr.  It states it has 130 w/c at 8ohms 2 channels, so I figure i'm only getting 37w/c with all 7 speakers right now, right?

The 37 watt number is based on tests with pure sine waves, all channels driven with the identical same signal, and resistive loads. That's completely different duty than playing multichannel music. Music has far less average power than pure sine waves with equal peak levels. Resistive loads have average loading that is greater than speakers with the same nominal impedance. In real music and drama, all channels are not driven with the same signal (we hope!). 105 dB SPL peaks are too loud for most people's preferences.
Quote:
.  Either way, it's not loud enough.  I bought it because it's got 9 or 11 preouts even though I run a 7.2 surround.  I'm thinking about a 5 channel amp somewhere around 150-200 w/c.  If I do that, I will have 2 channels left of the avr to push 130 w/c, right?

The biig problem is that the AVR may be still able to kick out 100+ wpc in actual use, and 200 wpc is only 3 dB more power. It takes 10 dB more power to give the subjective impression of "twice as loud".

Here's a very practical experiment - listen to your system at a typical level (not crank 'er up but typical comfortable listening level) and then click the volume on your remote up or down six clicks. It isn't that much change, right. That's what your proposed amp upgrade will do for you, if you are indeed already running your system into clipping.
Quote:
So, as long as I'm thinking right does anyone have a 5 channel amp suggestion?  Or maybe i'm wrong and need clarification, which would be usefull too.  Thanks,

From thousands of miles away I can't tell you whether you need more power or not. However, if you can express your situation in numbers, then we have something reliable to talk about.

(1) What are the loudest levels you are listening at now? To get a reliable number for that, obtain an inexpensive SPL meter that reads and holds peak levels with fast response. Here is such a thing for a price that anybody who is talking about major amp upgrades should be able to afford, and it is easy enough to use:

http://www.ebay.com/itm/Galaxy-Audio-Checkmate-130-dB-SPL-Sound-Level-Meter-/231137303014?pt=US_Pro_Audio_Parts_Accessories&hash=item35d0db59e6



Use a peak SPL calculator to estimate how much power you are currently using on peaks:

http://myhometheater.homestead.com/splcalculator.html

As the old saying goes " (Reliable) knowledge is power".

The above are not infallible, but they are probably better than nothing. ;-)

You might want to add at least 10 dB more power (10x watts) than you are currently using if you want a system that actually sounds much louder. Of course that kind of power may be hard on your existing speakers...

If your subwoofers are the typical active (self-powered with built in amplifiers) subwoofers, they significantly offload your AVR in your quest for loudness. They might allow your system to get 3-5 dB louder that it would without them. Make sure that your main speakers are set for small. BTW what are your speakers?

arnyk 01-28-2014 03:06 AM

Quote:
Originally Posted by sandydankness View Post

5-8 ohm speakers and 2-6ohm speakers plus 2 subs in a 2700ish cu. ft. room.  So are you saying it isn't cost effective to get an amp to increase volume? How much am I going to have to spend to get more db?

Rule of thumb is that the average impedance of a speaker is 1.5 times its nominal impedance. The average impedance of the resistive loads used in bench tests like those of S&V is identical with their nominal impedance. Therefore 6 ohm speakers might be a good match with 9 ohm resistive loads. Higher impedances are easier to drive - they take less current.

mastermaybe 01-28-2014 04:23 AM

6 Attachment(s)
"Although the Onkyo should not be your pre-amp since the pre-amp outs generally clip at 1Vrms on big box receivers like Onkyo, Yamaha, Denon, etc."

And Marantz, which is 98% a rebranded Denon?

Any evidence for this assertion in the first place, though? I own a Denon 4311- and have owned a dozen other mid/upper tier "big box" AVRs (you know, the $1000 to $2,000 "big box" AVRs) and I can assure you- and the OP- that none of them were clipping at 1 volt on the pre-out. That's zero.

Just an importantly, there are an exhaustive number of amplifiers that reach MAXIMUM OUTPUT with just 1-1.25 V's of input so it's even less of an issue, although, again, it's not one anyway.

The idea that someone has to purchase some over-priced, under-featured boutique receiver to align with someone else's misplaced assumptions and blind adoration...and use external amplifiers (that most times are ALSO not needed), is, I'm sorry, absurd.

I'm infinitely more inclined to agree with arnyk who seems to make much more sense than some want to believe in these parts.

Good luck and just get a better handle on what you really need.

James

lovinthehd 01-28-2014 05:26 AM

Assuming the OP has reasonably sensitive speakers, maybe he just wants really loud. Maybe his solution is higher sensitivity speakers. His speakers may not get much louder than he already drives them with his current amp. Kind of hard to have a discussion about bigger amps for his speakers without even knowing what speakers he's using or to what sound levels he really is driving them....

I'd also like to see some facts from Astrallite about the pre-out clipping on the OP's Onkyo (or other major brands & models)....

sandydankness 01-28-2014 08:15 PM

OK.  So I need an spl meter.  I would like to check my bass out too.  The galaxy only goes down to 125hz.  Before I drop some scrilla is there a meter that tests lower?

 

And Arnyk, I'm at work, I don't have a computer, so I can't tell you what the models are off the top of my head. But I do remember they have 89db sensitivity, and yes, my subs have their own internal amps, and the speakers are set to small.


lovinthehd 01-28-2014 08:36 PM

Quote:
Originally Posted by sandydankness View Post

OK.  So I need an spl meter.  I would like to check my bass out too.  The galaxy only goes down to 125hz.  Before I drop some scrilla is there a meter that tests lower?

I have an app called Musicians Spectrum that goes to 31 but does seem to drop off at 125...probably the limitation of the mic they use I assume. While the cheapest entry is Ratshack's spl meter, you might think about a calibrated USB mic if you have a laptop or similar can not only handle spl measurements with a download of REW but can be a much more useful tool for measuring your audio setup than a simple and limited Ratshack meter for 2-3x the cost....

What exact speakers are you using?

jevans64 01-29-2014 08:11 AM

Quote:
Originally Posted by astrallite View Post

Firstly, you are incorrect about the Onkyo 828's power output. Per sound&vision (test here)

It says these speakers are capable of 80W x 7 at 8 ohms. Are you trying to drive 7+ speakers that are all 4 ohm nominal in a large room? Then you may need more power.

Although the Onkyo should not be your pre-amp since the pre-amp outs generally clip at 1Vrms on big box receivers like Onkyo, Yamaha, Denon, etc. You probably won't drive an external power amplifier much louder than the internal receiver amps with such low quality line level signals. If you have to use an AVR, use Marantz SR6xxx line and above models, as they can put out a 4+ Vrms (check the Audioholics and S&V reviews) which will blow up a power amp before the receiver's pre-amp even starts clipping. Alternatively you could use a pure pre-amp like Emotiva UMC-200, although I think a Marantz receiver is a more cost-effective bet.

Also if you really want noticeably more power, you can't just use any separates amp, to beat the Onkyos by more than a few db would need multiple XPA-2s or XPA-1s, getting something like a couple of UPA amplifiers is not going to cut it and would be effectively a sidegrade.

I still think that the OP will be OK using the Onkyo as a pre-amp. The 828 isn't exactly the bottom end. The manual says that the pre-outs are rated for 200 mV with a maximum output of 4.6 V. My older Denon is rated for 1.2 V and max is 2.0 V. I have no problems clipping with an Emotiva 400w x 5 amplifier.

sandydankness 01-29-2014 10:15 PM

Quote:
Originally Posted by lovinthehd View Post


I have an app called Musicians Spectrum that goes to 31 but does seem to drop off at 125...probably the limitation of the mic they use I assume. While the cheapest entry is Ratshack's spl meter, you might think about a calibrated USB mic if you have a laptop or similar can not only handle spl measurements with a download of REW but can be a much more useful tool for measuring your audio setup than a simple and limited Ratshack meter for 2-3x the cost....

What exact speakers are you using?

I don't have a laptop or a plan on buying one anytime soon.  Any spl meters that can do that?


lovinthehd 01-30-2014 01:04 AM

No pc at all? SPL meters can't do what a mic can, but you can use spl meters for a few things, including REW but you need a pc to run REW as far as I know....you can see some possibilites here http://www.hometheatershack.com/forums/spl-meters-mics-calibration-sound-cards/10001-rew-cabling-connection-basics.html. With your phone app what kind of spl levels are you seeing when you have the sound at your higher listening levels?

sandydankness 01-30-2014 03:37 AM

Quote:
Originally Posted by lovinthehd View Post

No pc at all? SPL meters can't do what a mic can, but you can use spl meters for a few things, including REW but you need a pc to run REW as far as I know....you can see some possibilites here http://www.hometheatershack.com/forums/spl-meters-mics-calibration-sound-cards/10001-rew-cabling-connection-basics.html. With your phone app what kind of spl levels are you seeing when you have the sound at your higher listening levels?

Nope, I'm one of the few americans that's never had a pc, and ironically I'm 25 so part of the younger generation. I'm going to try and find that app, ill get back to you in a bit.

lovinthehd 01-30-2014 03:56 AM

That's ok, I just got my first smart phone.....but have had a pc almost your whole life....smile.gif

sandydankness 01-30-2014 04:05 AM

Quote:
Originally Posted by lovinthehd View Post

That's ok, I just got my first smart phone.....but have had a pc almost your whole life....smile.gif

Lol me too! I needed a phone for work when I got promoted (on call and other ****) so I actually have a cell now. I'm not going nuts and getting a computer too. Anyways, I got two apps and tried em both for comparison/validation. Both said I'm around 95 db and audessey has my speakers down around 5-6 db, so I figure I'm around 100 db max right now.

lovinthehd 01-30-2014 04:42 AM

That is with what kind of source? Movie? Music? Loudest part/passage?

Consider if your speakers are 89dB sensitive at 1w/1m, then at 1m you're getting 92 dB with 2w, 95 dB with 4w, 98 dB with 8w, 101 dB with 16w, 104 dB with 32w.....that's ignoring multiple speakers, and your actual LP but gives you an idea of how much power you're using now....

I resisted the cell phone even when I was working and the company thought nothing of having me spend my personal time answering some dumb ass' questions for free....I believe phones are for my convenience, not the other way around (unless you pay me significantly for such of course). Smart phone is a cool toy and the costs weren't as bad as last time I considered it. Can't imagine not having a laptop though. What do you use for accessing the forum?

sandydankness 01-30-2014 05:56 AM

The source is my xbox with music, I listen to metal so it's pretty much max volume all the time lol. Also, xbox live and my coomputer at work is how I get on here.


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