A few general questions about amps

Pycroft
Pycroft Posts: 1,961
edited October 2009 in Electronics
Hello again all, and welcome to another installment of, "Teach Pycroft". I have a few general questions about a possible setup and amp selection. I am not ACTIVELY looking, but more browsing craigslist/audiogon/ebay and trying to learn some things. here's the plan:

HK AVR 354
RTA 11TL's as fronts
CS400 as center
Monitor 30's as surrounds
Def Tech Prosub 800 as the sub.

Now here we go... QUESTION 1 I have two options - getting a five channel amp, or two amps - 2 channel/3 channel. Is there one option that is better or worse? My buddy George suggested two amps, this way if something goes wrong on one, you still have some amplification. The thoughts are a 2 channel amp to power the RTA's. At least 200 wpc, and hopefully more. Then a 3 channel amp to power the center and surrounds. I will hopefully add a preamp at some point in the future with HT bypass to better the 2 channel listening. The question is...does it matter if I power the fronts and center channel seperately? Should I focus on a 3 channel amp with at least 200 wpc to power the RTA's and CS400? Will that affect the sound of 2 channel listening at all? If so, would a good option be to just get a 3 channel amp to power the fronts and center and have the HK power the surrounds?

Question 2 The RTA's are listed at 250wpc I believe. Does that mean I should be searching for AT LEAST 250 wpc? Would getting something with 300 watts per channel or more be beneficial or will it harm the speakers? I'm assuming it wouldn't, but that's why I ask.

Question 3 This is the big one...I've read people say that amps can affect sound...How does a different brand amp affect the sound? Adcom, B&K, Carver, etc....do they have warm/harsh/vibrant timbre's in themselves? I was told that the amp is the workhorse and the preamp was the brains of the operation. Wouldn't the HK be the brains and affect teh sound, and the amp JUST provide the juice for the speakers? If amps do affect sound, are there ones to avoid in my situation?

Thanks in advance...and I look forward to learning about this!

James
2 Channel/HT:
Sony SS-M9 P's (ES version)
Sony SS-M1CN Center Channel
Polk RT800 Surround Speakers
Odyssey Stratos Dual Mono Amplifiers
TAD 150 Signature Tube Preamp
Harman Kardon HK354
Sony SACD Player
Post edited by Pycroft on

Comments

  • concealer404
    concealer404 Posts: 7,440
    edited October 2009
    1) I would say either a 5 channel or a 3 channel. But i would use the 3 channel to power your front stage, and leave the Monitor 30s powered off your reciever, they aren't too power hungry.

    2) You won't NEED at least 250wpc. It certainly wouldn't hurt, but you should focus more on quality, not quantity. RTA11TLs like power, though, so more is always good. Too much power doesn't kill speakers, distortion and/or clipping does. As long as it's clean power, 300wpc won't kill your speakers. Chances of you sending that full 300w is pretty slim anyways, your hearing will probably give out before you crank the volume knob enough to send every ounce of the amp to the speakers.

    3) Different amps sound different. I actually find that the amps change the sound more than the preamps/avrs. But yes, they all have their own "sound characteristics." So even though the HK has it's own sound, it may be changed completely depending on what amp you get.
    I don't read the newsssspaperssss because dey aaaallllllllll...... have ugly print.

    Living Room: B&K Reference 5 S2 / Parasound HCA-1000A / Emotiva XDA-2 / Pioneer BDP-51FD / Paradigm 11se MKiii

    Desk: Schiit Magni 2 Uber / Schiit Modi 2 Uber / ISK HD9999

    Office: Schiit Magni 2 Uber / Schiit Modi 2 Uber / Dynaco SCA-80Q / Paradigm Legend V.3

    HT: Denon AVR-X3400H / Sony UBP-X700 / RT16 / CS350LS / RT7 / SVS PB1000
  • jimmydep
    jimmydep Posts: 1,305
    edited October 2009
    Hey Jim, Lot's of good questions, but I'd like to comment on #3. Let's forget about brands for a moment and concentrate on the different sound qualities of amps. I have 3 different brands of power amps, each one has a very distinct sound, not better or worse, just different. To my ears I prefer the sound qualities of one of these amps over the other two, BUT, I’m beginning to appreciate the subtleties of the other amps also.

    I'm fairly new to this hobby, so I respect the experiences of other Polkies, and use them to guide me in new directions, but I am a Hear for myself type of guy, so in the end, let your ears be the judge.


    Jimmy
  • reeltrouble1
    reeltrouble1 Posts: 9,312
    edited October 2009
    1. Your good friend George is just that, go buy him lunch. Get the very best two channel amp you possibly can to power your two front mains.

    2. No, forget the watts issue, jump on the polk info section and read about how all watts are not created equally. You want a high current amplifier, you want to know the ampre pk2pk rating it should be at least 30 but the more the better, we are talking solid state amps. You can though get as many watts as you want, a quality amp will not harm your speakers despite the watt rating, also, you dont really need 200 watts to run your speakers, again you need a high current amplifier.

    3. Despite the fact the Polk Peanut Gallery has indicated in prior posts their notion of BS and a lack of common sense, suggestions of the nth degree and all manner of anecdotes the fact is they are correct, I have no common sense about audio, of course neither do they. So as they lick the salt off their fingers read there comments and research everything we say and make up your own mind, Of course the result of our help is a bit of a confused spin for you to muddle threw.

    So then, each amplifier circuit is a design of its audio creator, someone sat down and decided to bulid either a more effective amplifier or a more cost effecient amplifier at a certain price point, never confuse efficiency with effectiveness, two totally different concepts....so every piece of every amplifier can and does effect the sound signal as it passes through it to at least some degree, some very small, some large. The number of gain stages, the board design and wiring or traces, the capacitors used, the type and number of resistors, the vibration node points of the case, the wire used inside and on and on, so yes as you say amplifiers become known as warm, soft, detailed, bright, harsh.....Mr. Gordon Holt gave us this language and all of it is subjective, you can of course measure on scopes outputs and all sorts of things but you cannot measure how it sounds to you. Yes your H&K is the brains and the amp the brawn, well, at least in this simplified explanation here but learn about impendance and how it plays a part, so you recall I told your H&K is full of signal degrading parts and this is very true, but OK your doing HT and you need it and budget and all of those things, but understand this, an AVR is a compromise to efficiency in terms of convenience and cost to effectivness in handling of the audio signal, especially the audio musical signal. That said we are very fortunate these days that nearly everything sounds pretty damm good, even avr receivers, so many many folks start as you, with an AVR and some amps, frankly if you got a nice two channel amp you would be fine using the H&K for your surrounds but knock yourself out if you want a three channel as well, I would get a pre designed to play music with that dough, you could even just change the speaker wires as you switch back from music to HT if you wished, some do exactly that until they get a pre with HT by-pass.

    Most of all enjoy yourself, trust your ears, they will tell you when to stop and be done, however, your free to join me anytime in the big audio Rabbit Hole, in fact you are already there, now you pick your path.

    RT1
  • cnh
    cnh Posts: 13,284
    edited October 2009
    See my post in your other thread, I anticipated some but not all of these questions.

    Jimmy is absolutely right. Different amps have slightly varying properties...but a good Power amp should produce a more 'neutral' sound that will then be modified by the properties of the Pre/pro...there are, though, synergistic effects between the two and your cabling as well! Not to mention your source!

    Everything interacts with everything.

    2 or 3 channel amp. That's your call. If you're into HT then go with a 3 channel first.
    If you play more music go 2 first and then 3. Just make sure you get similar amps for both 2 and 3 channel...perferably from the same manufacturer.

    Finally, and you can read this hundreds of times on this site. YOU CAN NEVER HAVE TOO MUCH POWER! More power does not fry speakers, less power does--not having enough causes distortion and clipping too easily!

    Reeltrouble1 is giving some solid advice that we could all learn something from above and in much greater detail than I have.

    Good luck
    cnh
    Currently orbiting Bowie's Blackstar.!

    Polk Lsi-7s, Def Tech 8" sub, HK 3490, HK HD 990 (CDP/DAC), AKG Q701s
    [sig. changed on a monthly basis as I rotate in and out of my stash]
  • Pycroft
    Pycroft Posts: 1,961
    edited October 2009
    Great info all. I'm not sure I gave the best wording to one of my questions. If I'm looking to eventually have a pre with HT bypass to improve the 2 channel sound, would it affect the sound getting a 3 channel amp for the fronts and having the RTA 11TL's and CS400 powered by the same. I think it's more a wiring question...would I have to plug speakers or amp into the pre? if so, and I have the CS400 on the same amp as the RTA's, will it affect the sound? If it doesn't matter, I guess I can look for a 3 channel amp that's 250 wpc +?

    Thanks again,

    James
    2 Channel/HT:
    Sony SS-M9 P's (ES version)
    Sony SS-M1CN Center Channel
    Polk RT800 Surround Speakers
    Odyssey Stratos Dual Mono Amplifiers
    TAD 150 Signature Tube Preamp
    Harman Kardon HK354
    Sony SACD Player
  • cnh
    cnh Posts: 13,284
    edited October 2009
    Since you would always plug the speakers or wire to the amp for power...this isn't much of an issue.

    I think you have a diagram of the HT bypass in the other post...take a good look at it.

    Personally I'm with Reel... get a nice 2 channel first! That will work for you fine, as that is the most important for 'music'.

    cnh
    Currently orbiting Bowie's Blackstar.!

    Polk Lsi-7s, Def Tech 8" sub, HK 3490, HK HD 990 (CDP/DAC), AKG Q701s
    [sig. changed on a monthly basis as I rotate in and out of my stash]
  • vc69
    vc69 Posts: 2,500
    edited October 2009
    +1 on a good 2ch amp first.
    -Kevin
    HT: Philips 52PFL7432D 52" LCD 1080p / Onkyo TX-SR 606 / Oppo BDP-83 SE / Comcast cable. (all HDMI)B&W 801 - Front, Polk CS350 LS - Center, Polk LS90 - Rear
    2 Channel:
    Oppo BDP-83 SE
    Squeezebox Touch
    Muscial Fidelity M1 DAC
    VTL 2.5
    McIntosh 2205 (refurbed)
    B&W 801's
    Transparent IC's
  • cfrizz
    cfrizz Posts: 13,415
    edited October 2009
    If you have space & outlets to handle 2 amps go for it. If not, get a 5 channel & enjoy.
    Marantz AV-7705 PrePro, Classé 5 channel 200wpc Amp, Oppo 103 BluRay, Rotel RCD-1072 CDP, Sony XBR-49X800E TV, Polk S60 Main Speakers, Polk ES30 Center Channel, Polk S15 Surround Speakers SVS SB12-NSD x2
  • doug lang
    doug lang Posts: 261
    edited October 2009
    I hate to repeat what has been said, what kept me from two amps was the space and outlets. Surely you could work around this. Myself I went with the five channel. And bigger is indeed always better. Good luck.
    Oppo bdp 93 Blue Ray
    Integra DTR-80-2
    Polk LSi9s (mains)
    Polk LSiC (center)
    Polk LSiFXs (surrounds)
    Sub SVS 20-39+
    Samsung 60" Led 3-d
    Blue Jean Cables