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I've seen various responses to this topic. Before trying it would like to know if there there would be any noticeable improvement in using my RX-V1200 as a pre/pro and buying an external amp. Receiver is working fine and just looking for better SQ. If it wasn't for the HDMI "thing", I think I would buy a pre/pro and be done with it. However, if I can make some improvement now with an amp that can be used later on if I go the dedicated pre/pro route, then it might be worth doing. I currently have Studio 20s, Servo 15, CC470, and ADP 470. Thanks in advance.
 

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a good amp should not alter the sound just amplify it

a rec or prepro with better processing will improve the

sound if you are playing your music louder than your

rec has headroom than an amp will relieve the strain.
 

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All amps have a "signature" sound, so depending on the amp you choose, there will be some difference in sound, as an example, Anthem gear will be a bit more forward in nature, ie, highs, and mids come through stronger than the bass notes, whereas a rotel is more laidback and will not emphasize the highs as much, Higer end amps like Theta, Bryston, Levinson will not emphasize any specific area, and are more nuetral, meaning everything is a bit more equal, but provide the reserve power and punch of the lower frequencies that the others I've mentioned will not be able to replicate. (many more, these are just quick examples)

The choice of amp WILL make some difference in the presentation, typically not noticed by everyday listeners like most of my friends, and my wife, but to me, I can notice the differences.

If you are asking this question, I would tend to think you are just looking for more power and should have many options, but in short, if you buy a seperate amp, your headroom will increase, your speakers will sound better, and you will be able to upgrade later w/o worrying about the power side of your setup, which will give you more options as you go along in this endless quest.
 

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Im in the same boat as the OP. I was thinking about adding a 2 channel amp to power my 2 fronts w/ my receiver and just have the receiver power the rears and center. Now i am wondering what amp would be a good deal and how many watts i would need for my speakers to really benefit. The speakers are 250 watts. Any suggestions?
 

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My advise to you xgen is to get a 3 channel amp, and power all front 3, as opposed to just the L/R, especially if you do alot of HT.

The speakers dont have "watts" ( thats another forum members great line ) But they will handle a certain amount of wattage supplied to them. I would personally get something that is equivalent, or more as far as power output is concerned if you want them to perform at their optimum. Many choices, budget will be determining factor in what you should demo, and ultimately purchase. Something along 150-200wpc would do just fine as long as its good clean power, with lots of headroom.
 

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Its all about the effeciency rating of your speakers and how hard they are to drive (ohms) and the levels that you will push it too.


Speaker A: 85db sensitivity


Power

SPL


1 watt

85 db


2 watts

88 db


4 watts

91 db


8 watts

94 db


16 watts

97 db


32 watts

100 db


64 watts

103 db


128 watts

106 db


256 watts

109 db


512 watts

112 db


Speaker B: 91db sensitivity


Power

SPL


1 watt

91 db


2 watts

94 db


4 watts

97 db


8 watts

100 db


16 watts

103 db


32 watts

106 db


64 watts

109 db


128 watts

112 db


256 watts

115 db


512 watts

118 db


In this example you can see how the speaker efficiency has a HUGE difference in what it takes to drive the speaker properly..overlooked by many people when trying to determine amp needs...

A speaker with a rating of 91db efficiency can do a loudness level of 112db with only 128 watts from the amp.

Meanwhile the speaker with the efficiency rating of 85db would take 512 freakin watts from the amp to do the same loudness level of 112db (all other things being equal like environment,ohms etc)


This is the exact reason why I switched form my Aerial setup to my current Von Sweikerts...the Aerials required thousands of dollars in good external amplification while the Von Scheiwkerts can be driven just as loudly with a Denon 2807

Aerials (4ohms and 84db effecient)

Von Scheikerts (8 ohms and 89db effecient)


What is the effeciency and ohm rating of your speakers ?


Assuming the amp is of sound design and is operating properly .. The important thing is to make sure that you dont drive the amp to "clip"


An amp shouldnt have its "own" sound unless the manufacturer has intentinally altered it ..if designed properly all the amp should do is amplify the signal. Being a former amp slut having gone thru 50~60 amps in the last ten years, I have changed my ways and wont "waste" money on anything that isnt needed..Again, with effecient easy to drive speakers you shouldnt hear a spits worth of difference assuming the amp is operating properly and not driven into "clipping".
 

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Quote:
Davidpa lets say i bought a 3 channel amp to power the front 3. Would that take strain off my receiver and will it then send more power to the rears because of the amp powering the front 3

Im not David but yes thats correct ...Your internal amp of your reciever only has one transformer for all your channels ...if you add an3 channel external amp that will take some of the load off of the internal amp ...That is an excellant idea and I did that exact same thing for years ..

Some good 3 channel amps Ive had and would reccommend:


Earthquake Cinenova Grand ..this things a beast, it has 3 seperate huge torodial transformers..One for each channel, 300 watts @ 8 ohms and doubles all the way down to 2ohms (1000 watts and stable ) used market 800.00 equals STEAL


Parasound 2003 ..200 watts X 3 @ 8 ohms ..750.00 used

Rotel rb ( I forget model number ) but 200 watts x 3 @ 8 ohms ..750.00 used

Adcom 3 channel ..same specs as above but can be had a little cheaper


PS. Ive found in a HT environment that the CENTER CHANNEL actually seems to take more juice then the main speakers...Thats why a 3 channel amp ( if you even need an external amp to begin with) is an excellant way of using your money ..if you have a reciever and not a pre-pro, why not use the amps in your reciever for the less critical back 4 speakers, plus as said your taking the strain off of your reciever
 

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Thanks for all the info and i am beginning to understand all this amplification stuff more and more. Btw my speakers are 92 db @ 8 ohm fwiw. (jbl s312) I am also using the denon 3805. I was just curious if i would see much of an improvement using a seperate amp. But you (psujohny) have me convinced to maybe just save the money.
 

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I'm going to thread-jack here, same question.


I was also thinking of adding some external amplification for my speakers.


I have 3 Ascend 340SEs (90dB/1w ane, 92dB in-room according to specs), 2x 170SEs in the back, a HSU VTF-3 MK2 sub (room treatments, bass traps, BFD).


My receiver is an HK 240, with 65x2 in stereo and 55wpc for multichannel. This is HK watts, so very conservative.



Would adding something like an Onkyo M-282 ( http://www.vanns.com/shop/servlet/it...ails/531299905 ), or maybe something like 2 of these Audiosource amps bridged ( http://www.amazon.com/gp/product/B00...491256-0791954 ) give me bigger/better sound? Maybe the Emotiva LPA1 (6x125w) for $500 - http://emotivaaudio.com/lpa1.html ?


If I was going to spend something like $750 on amplification, I'd rather just upgrade to a more powerful receiver around that price range anyway. My HK 240 retailed for $800, but I got a refurb for about $250.
 

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That Emotiva looks like it has pretty decent specs for that price..I havent did any amp shoping lately ..what kind of reviews does it get ?


Since you have a HK reciever and your speaker are fairly effecient you may want to check into buying a used HK PA5800 5 channel amp ..It can be had for around 250.00 and is a good solid high current amp thats does an excellant job ..should be all you need for your Ascends.


PS. I wouldnt even bother with the M-282.

If you plan on updating your reciever soon ( for hdmi, new audio formats etc.) ..imo you'd be better off putting your funds into it ..I know you could get a middle lined reciever that would drive those Ascends properly. But again a used HK PA5800 is so cheap that you could always use it down the road to "supplyment" your new reciever.
 

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Quote:
Originally Posted by psujohny /forum/post/0


Its all about the effeciency rating of your speakers and how hard they are to drive (ohms) and the levels that you will push it too.



What is the effeciency and ohm rating of your speakers ?

psjohny..how does the ohms rating affect your examples? It would seem intuitive (but probably wrong) to assume you would need only half as much wattage to drive a 4 ohm speaker vs an 8 ohm speaker.


Ray


Edit: I guess it depends on what remains constant. Given Ohms law (learned this many many years ago and haven't used it since) where I=V/R if voltage is constant and and resistance is halved from 8 to 4 ohms then the receiver would have to deliver twice as much current to the speaker. I know this is a DC formula but I am guessing there is a related AC impedance effect) This may be completely off base, however.
 

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First of all adding an external power amp will improve Any avr's sound output since the avr will be used as a preamp and the strain will be taken off the avr and the power will be generated by the amplifiers,

I am using 3 amps to power 5 channels of my Yamaha htr5790 and it has made a dramatic improvement on sound quality and dynamics..

I am using 2 audiosource amps for the front 3 channels and an onkyo m-282 to drive the side surrounds and the onkyo is a low priced amp but it cranks pretty good for 200 bucks.
 

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Im too late to add much, but I will say this anyhow. Any time you can take the load off of the reciever you are doing yourself, and the reciever a favor. The reciever cant deliver stated watts anyhow, so by reducing the load of the front 3 channels, the rears will have a "bit" more to work with now, but will they be able to deliver the rated power now? No, probably not, BUT, they wont have to produce the main dialogue, or do it with more than one channell being driven. So in effect the remaining channels will have a bit more to give, since they dont have to share as much as before. PLUS most surround and rear channel information is just effects, so the load becomes even less, and in dynamic scenes it will come through more dynamic. Laymens terms, but useful info I think.
 

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The ohms play a huge part because of resistance. Lower the ohms, the harder the amp has to work, and most recievers just cant do it, and even if they can, it wont be at higher volumes, or without distortion.

But regardless if you have 8 ohm, or 6ohm speakers, a seperate amp will still provide your best performance.
 

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Quote:
Originally Posted by psujohny /forum/post/0


That Emotiva looks like it has pretty decent specs for that price..I havent did any amp shoping lately ..what kind of reviews does it get ?


Since you have a HK reciever and your speaker are fairly effecient you may want to check into buying a used HK PA5800 5 channel amp ..It can be had for around 250.00 and is a good solid high current amp thats does an excellant job ..should be all you need for your Ascends.


PS. I wouldnt even bother with the M-282.

If you plan on updating your reciever soon ( for hdmi, new audio formats etc.) ..imo you'd be better off putting your funds into it ..I know you could get a middle lined reciever that would drive those Ascends properly. But again a used HK PA5800 is so cheap that you could always use it down the road to "supplyment" your new reciever.


Thanks for the advice.


I'm seeing what I can find on the LPA-1. I at least know it used to be $700, through **********. Now it's $499.


But it seems like the PA5800 wouldn't be much of an upgrade. 80wpc compared to the 55wpc I have now...
 

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Quote:
Im too late to add much, but I will say this anyhow. Any time you can take the load off of the reciever you are doing yourself, and the reciever a favor. The reciever cant deliver stated watts anyhow, so by reducing the load of the front 3 channels, the rears will have a "bit" more to work with now, but will they be able to deliver the rated power now? No, probably not, BUT, they wont have to produce the main dialogue, or do it with more than one channell being driven. So in effect the remaining channels will have a bit more to give, since they dont have to share as much as before. PLUS most surround and rear channel information is just effects, so the load becomes even less, and in dynamic scenes it will come through more dynamic. Laymens terms, but useful info I think.


Point taken! I was browsing 3 channel amps upon your suggestion. I found an adcom amp (200 wpc) that retailed for apx 1300 that i can get for around 500 or so. (pretty good deal i thought). However after reading psujohny's theory, He has me reconsidering for the time being. Thanks for the help though!
 

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Quote:
First of all adding an external power amp will improve Any avr's sound output since the avr will be used as a preamp and the strain will be taken off the avr and the power will be generated by the amplifiers,

Umm ok, also a 300.00 speaker cable will sound better then a 50.00 cable. A 500.00 power cord will sound better then a 10.00 stock one. Personally, I have a ratio for bang for the buck..I mean if I have a set of 500.00 speakers, Im not gonna spend 300.00 on a speaker cable...,even if it does add a 3% sound quality increase.

In theory your are taking away strain from the reciever and Id assume there is some benifit , But If you have effecient easy to drive speakers and get a reciever thats honestly rated and of proper design and you dont drive the amp into clipping, then adding an expensive external amp will get you a very small return imo ( versues the money spent ). Sorry let me say that this is just my opinion but Ive been thru more freakin amps then I care to count. Ive gone thru the trouble of doing actual blind a/b-ing switching in/out etc. Ive spent tons of time toiling away with amps ( pro-amps, boutique amps, cheap amps, very expensive amps )...and after all that, being totally honest with myself ( blind testing can be very eye-opening..differences I thought I heard went away very quickly with the blind testing method ) I gotta say that given that the above circumstances are met, it just aint worth it, again imo.
 
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