-

Jump to content



Photo
- - - - -

difference between using a receiver and a pre-amp processor


This topic has been archived. This means that you cannot reply to this topic.
51 replies to this topic

#1 of 52 felix_suwarno

felix_suwarno

    Screenwriter

  • 1,530 posts
  • Join Date: Dec 02 2001

Posted November 29 2005 - 11:11 AM

guys, i am going to go separate route sometime next year. so i am doing a little shopping around now.

a shop owner demoed his system yesterday and i was blown away. the sound was really crisp and powerful with smooth and airy highs. the sub was really powerful as well.

he had
sherbourne pt7000 as processor
a meridian ( forgot the type ) amplifier
an m&k subwoofer with 2 12 inch woofer ( perhaps an mx 5000 m? i forgot )

but they are sooo damn expensive! now i have tons of questions.

my new room is 2.8 meter in height, around 4.5 meter wide, 11 meter long. there will be treatment installed on the wall.

i will be using monitor audio gold reference series all around.

my questions :
- what is the difference between using a receiver and using a processor as a pre-amp?
- can i just use my old denon avr2802 to produce acceptable sound quality?
- i want 7.1 setup, but can i just use a 5 channel amp and let the receiver power the rest of the 2 back channel? what happened if i cranked up the system?...will these 2 channels / speakers be damaged because there is not enough juice to drive them?

- any recommendation on a nice processor / a nice receiver that can be used as pre-amp?
- any recommendation on a 7 channel amplifier ( 200 watt per channel ) around 2500 dollar? ( i am considering sherbourne 7/2100a )

thank you.

#2 of 52 RAF

RAF

    Lead Actor

  • 7,062 posts
  • Join Date: Jul 03 1997

Posted November 29 2005 - 02:28 PM

Just to get the ball rolling (but by no means the only options to consider):

The new Outlaw 990 pre/pro appears to offer tremendous bang for the buck as do a lot of their amps in various configurations. You might want to check out their website (outlawaudio).

As to subwoofers: check out the SVS subs (SVSound). I have M&K speakers and one of those 2 12" subwoofers that you mention (the M&K MX-350THX). When I got my SVS Ultra I retired the M&K - it was that good.

Both companies are, I believe, "internet only" but both allow you to audition their products in your home for just the cost of shipping.

Happy hunting.
RAF
[Demented Video Dude since 1997]
[Computer Maven since 1956]
["PITA" since 1942]
CLICK HERE to visit My HT HTF Rules and Regulations

#3 of 52 mackie

mackie

    Supporting Actor

  • 568 posts
  • Join Date: Feb 07 2004

Posted November 29 2005 - 04:11 PM

You might consider adding an amp to your current receiver and see what you think. There are lots of amps in your price range, but for a complete separates system your choices will be limited unless you go the used route.

Also, consider that a 200w amp only plays 3db louder than a 100w amp. What are the ohm rating and sensitivity of your speakers?

The outlaw prepro seems to be a good piece of equipment, and I own a couple of outlaw M200 monoblocks and they work pretty good.

#4 of 52 felix_suwarno

felix_suwarno

    Screenwriter

  • 1,530 posts
  • Join Date: Dec 02 2001

Posted November 29 2005 - 04:54 PM

guys, i live in indonesia. the shipping cost from united states would be really expensive. at this point i am only considering importing an svs. if the outlaw marketing dept could give me a good deal, well, yea i will consider it as well. but really, shipping things half a planet away sounds risky to me.

"Also, consider that a 200w amp only plays 3db louder than a 100w amp. What are the ohm rating and sensitivity of your speakers?"

i am going to use monitor gold refs, and they are between 88-90 db sensitivity.

but current setup is yamaha rx-v730 ( 100 wpc ), boston vrm50 and vrmc on the front , psb image 1b surround, svs ps10isd. my room is big with 2 openings on the right and behind ( it is my living room, not a dedicated theater ).

the only one which seems to be able to squeeze more decibel is the pb10isd. everything else sounded a little bit muffled when there are explosions going on. but for music, i am still very happy with this setup. the bostons are fantastic.

so, i was thinking perhaps by using a 200 wpc amp the system would still be stable when there are loud sound effects going on. the demo system i heard a few days ago at the shop sounded like...i dunno, it was like they didnt even try to go loud and they were already VERY loud. loud, but pleasing. no sound stretching at all. that is why i am thinking of using separates.

#5 of 52 mackie

mackie

    Supporting Actor

  • 568 posts
  • Join Date: Feb 07 2004

Posted November 29 2005 - 11:12 PM

Okay - being in indonesia does make a difference. Check out Parasound, Adcom, Rotel,and the Sherbourne for starters.

All power ratings are not equal. The power supplies in separate amps are usually more robust than the ones in your receiver and will not start clipping or run out of headroom as fast as the ones in a receiver. All things being equal, more power is better than less power, but a true 100RMS amp will drive all but the most difficult speakers in huge rooms to hearing damaging levels especially if you use a sub and and send everything below 80hz to it.

There can also be other reasons for the sound difference too. Room acoustics, setup, the speakers themselves, the associated equipment.

#6 of 52 felix_suwarno

felix_suwarno

    Screenwriter

  • 1,530 posts
  • Join Date: Dec 02 2001

Posted November 30 2005 - 03:47 AM

thanks for the reply, macky.

"a true 100RMS amp will drive all but the most difficult speakers in huge rooms to hearing damaging levels especially if you use a sub and and send everything below 80hz to it."

so, a 200 wpc MIGHT be too much for me? i am trying not to overpay the dealer by buying stuff i dont really need. perhaps a 125 to 150 wpc would be enough?

if i can only demo lots of system all at once at the same room....jezzz

#7 of 52 felix_suwarno

felix_suwarno

    Screenwriter

  • 1,530 posts
  • Join Date: Dec 02 2001

Posted November 30 2005 - 03:51 AM

by the way, how many watts per channel does a speaker need if it is rated at 88 db ( sensitivity ) ?

i do want some head room in my system's sound output.

#8 of 52 John S

John S

    Producer

  • 5,460 posts
  • Join Date: Nov 04 2003

Posted November 30 2005 - 05:39 AM

Room size has the most to do with this....

88db 1 watt 1 meter.....

Says nothing about how to get it to produce 110db at the seating position of a large room.

#9 of 52 rob-h

rob-h

    Second Unit

  • 263 posts
  • Join Date: Jul 06 2005

Posted November 30 2005 - 05:50 AM

A 100 watt per channel amp may drive a speaker to loud levels in a large room, but it wont do it cleanly.

#10 of 52 mackie

mackie

    Supporting Actor

  • 568 posts
  • Join Date: Feb 07 2004

Posted November 30 2005 - 07:02 AM

John is correct that room size affects this, but also the distance from the seating position and how loud are you going to go?

How far do you sit from your speakers?

I really don't think that anyone will listen at 110db for very long. At those levels you can suffer permanent hearing damage fairly quickly, plus it's uncomfortable.

I suspect most listening is done in the 75 to 90 db range.

Quote:
A 100 watt per channel amp may drive a speaker to loud levels in a large room, but it wont do it cleanly.


That depends on a number of factors, but a 200w amp will only play 3dB louder than a 100w amp.


Quote:
so, a 200 wpc MIGHT be too much for me? i am trying not to overpay the dealer by buying stuff i dont really need. perhaps a 125 to 150 wpc would be enough?


200 watt amp can produce 3bd more than a 100 watt amp. A 100 watt amp can only produce 3 db more than a 50 watt amp. The more watts the more it costs.

Use your speakers for example. 88db at 1 meter x 1 watt. 2 watts gives you 91db, 4 watts = 94db, 8 watts = 97db, 16 watts = 100db, 32 watts = 103db, 64 watts = 106db, 128 watts = 109db, 256 watts = 112db.

Quote:
if i can only demo lots of system all at once at the same room....jezzz

Only you can decide how much amp you need, and all things being equal it's better to have too much power than not enough.

This hobby can be maddening since there are so many variables and compromises that have to be factored into your decision. There are hardly any absolutes in this game and no perfect systems. I feel the best approach is to do the research and make an informed decision based on the information you have. Be wary of making decisions based only on what sales people say, and take everything you read on these forums with a grain of salt.

It is best to listen in your room, but you don't have to have everything side by side. When you listen take lots of notes. It is true that speakers sound differently in different rooms, but they will retain the basic sound no matter what room you choose. A klipsch speaker is going to sound like a klipsch speaker no matter where you listen. Same with Paradigm and others. The room will affect clarity, sound-staging, detail resolution, bass performance... but it won't make it sound like a different brand of speaker.

#11 of 52 Kevin T

Kevin T

    Screenwriter

  • 1,407 posts
  • Join Date: Jul 12 2001

Posted November 30 2005 - 07:38 AM

Quote:
Use your speakers for example. 88db at 1 meter x 1 watt. 2 watts gives you 91db, 4 watts = 94db, 8 watts = 97db, 16 watts = 100db, 32 watts = 103db, 64 watts = 106db, 128 watts = 109db, 256 watts = 112db.


these figures are only true for 1 meter away from the speaker. who here sits 1 meter away from their speakers? i can't remember the exact numbers, but i think he needs to subtract 3dB for every 1 meter distance he is from his speakers.

for example, if his amp puts out 128 watts, his speakers will put out 109 dB at 1 meter, 106 dB at 2 meters, 103 dB at 3 meters, 100 dB at 4 meters, and so on and on.

Quote:
Only you can decide how much amp you need, and all things being equal it's better to have too much power than not enough.


i absouletely agree with this statement 100%. it's better to have the power and not need it than to need the power and not have it.

kevin t
religion is the opiate of the masses

#12 of 52 mackie

mackie

    Supporting Actor

  • 568 posts
  • Join Date: Feb 07 2004

Posted November 30 2005 - 07:53 AM

Quote:
these figures are only true for 1 meter away from the speaker. who here sits 1 meter away from their speakers? i can't remember the exact numbers, but i think he needs to subtract 3dB for every 1 meter distance he is from his speakers.


That's my understanding too, but the ratio will be the same regardless of if it's a 50, 100, or 200 watt amp.

This also changes when you add speakers and this is important since most of us use more than one.

I put this down just as a demonstration of how this works.

Just about everything in this hobby is relative and subjective...

#13 of 52 John S

John S

    Producer

  • 5,460 posts
  • Join Date: Nov 04 2003

Posted November 30 2005 - 10:01 AM

Hmm 110db sustained, isn't that out of line.


Posted Image I do like it very loud. I actually consider this reference level.

#14 of 52 mackie

mackie

    Supporting Actor

  • 568 posts
  • Join Date: Feb 07 2004

Posted November 30 2005 - 10:14 AM

Quote:
Hmm 110db sustained, isn't that out of line.


Ouch! About 10 years ago I would've agreed with you, but now it hurts to listen at that level for very longPosted Image

#15 of 52 felix_suwarno

felix_suwarno

    Screenwriter

  • 1,530 posts
  • Join Date: Dec 02 2001

Posted November 30 2005 - 04:56 PM

my seating area is located ( imagine a three "seating" sofa with me in the middle ) is around 2.5 meters away from the center channel speaker at the top of the tv. the left and right surround are about 1.5 meter from me. the sixth and seventh back channel are less than 1 meter away.

the problem : i dont know how loud 110 db is. i just want the system to produce unrestrained sound. do i want 110 db? i have no idea.

#16 of 52 felix_suwarno

felix_suwarno

    Screenwriter

  • 1,530 posts
  • Join Date: Dec 02 2001

Posted November 30 2005 - 05:28 PM

oh by the way.

if the sound produced by my current system sounded like it was stretching ( uh, trying too hard to be stable when there is loud sound effect going on ), can i blame it on the receiver alone? i am using yamaha rx-v730 with 100 watts per channel. does that mean that the yamaha doesnt really output 100 watts? or perhaps the power during loud sound effect has to be multiplied ( in real time ) ? what is the component inside that is supposed to multiply the power output when needed? is it the processor?

#17 of 52 mackie

mackie

    Supporting Actor

  • 568 posts
  • Join Date: Feb 07 2004

Posted December 01 2005 - 03:08 AM

110 db is like a rock concert. Not the back rows but up-close and personal... I remember a Ted Nuget conert I went too a long time ago where I was up close to the stage, and my ears rang for 3 days after it endedPosted Image

I don't suspect the yamaha receiver is putting out a true 100watts with 5 channels. Most don't, so I wouldn't get too upset about it.

BTW, You have really good speakers, and you should be able to get great sound at your seating position. IMO, I wouldn't necessarily say the Monitor Gold series is a huge upgrade over what you have.

Get a sound meter and make sure all of your speakers are playing at the same levels. You can't do this by ear, and it'll let you know how loud 110 db really is. Radio Shack sells an inexpensive model that works well, but there are more expensive professional models too.

Your room dimensions are similar to mine, and your seating position is a little closer than I sit. Make sure your speakers aren't sitting up against a wall. Try and pull them out at least .5 meter, and try to make sure they are at least that far from a side wall. If you have a TV between them, make sure the front of the speakers are even or slightly in front of the object. Try to form an equilateral triangle with you being at one point of the triangle. For you center channel, make sure the tweeter is aimed at ear level.

Also, room acoustics play a huge role in sound quality and is most likely as much of the problem as your equipment. The frustrating part is the same problems you're currently having will plague whatever system you have unless you do something them. You mentioned getting sound treatments. Try doing the treatments before you buy any other equipment. Sound treatments aren't equipment specific, so you they'll pretty much work with whatever equipment you have. You might just be surprised at how this cleans everything up.

The only concern I have about your set-up is that the VRM50's have a 5.25 inch woofer which might be too small for your room. All the power in the world won't fix that. The VRM 60, 80, or 90 might be what you need.

#18 of 52 rob-h

rob-h

    Second Unit

  • 263 posts
  • Join Date: Jul 06 2005

Posted December 01 2005 - 05:35 AM

Like I said, clean is the problem. You will get spikes that will cause major clipping. If you like to listen very loudly in a large room, you need more power.

#19 of 52 Dick Knisely

Dick Knisely

    Second Unit

  • 372 posts
  • Join Date: Oct 22 2005

Posted December 01 2005 - 05:40 AM

110db is a level that if sustained WILL cause injury.

"Excessive sound levels or "noise" (unwanted sound) can produce hearing loss that is temporary, permanent, or a combination of temporary and permanent. Since noise-induced hearing loss cannot be repaired or cured, the Washington State Department of Labor and Industries, Division of Industrial Safety and Health, had adopted a permissible exposure level (PEL, see next paragraph) of an 8-hour time weighted average (TWA) of 85 dBA for noise, which is designed to guard against unnecessary hearing damage (WAC 296-62-0901). Values equal to or below these levels are considered acceptable for industrial noise exposure without the use of hearing protection."

In an industrial setting, sounds at that level require hearing protection for even brief exposure.

There are a lot of 40-somethings in the world today with substantial hearing loss, comparable to what their grandfather's sustained as a result of noise exposure in WW2 combat but they got it at rock concerts when they didn't care. Now they're shopping for hearing aids.
I am not young enough to know everything. -Oscar Wilde-

#20 of 52 felix_suwarno

felix_suwarno

    Screenwriter

  • 1,530 posts
  • Join Date: Dec 02 2001

Posted December 02 2005 - 02:23 PM

mackie and everyone else, thank you for your responses.

so, what is the advantage of using separates in terms of sound quality? will the amp make the sound better? or simply louder?


Back to Receivers/Separates/Amps



Forum Nav Content I Follow