Amp for 804s

[moosepapi]

I am looking for a reasonable amp ($) for my 804s. Many of you have more experience with that than I do. I am currently looking at Rotel RMB-1565 for $1,100 and an ATI 1506 for the same. I want to stay around $1k. I would be bi-amping my center and r/l speakers and running my surrounds off my receiver.

[stuofsci02]

I have an RMB-1565 at my house right now on loan.. I am not using on my 804s, but I can try it if you like...

IMO without even trying it, I don't think it is a good choice.. The 804s can definately do with more then 100 wpc (even if you biamp two channels). I have tried the 804s with the RMB-1575 which is the 250 wpc version and I did not like it very much.. Something seemed off, which I attribute to the Class D topology..

I can say for sure that I like my Emotiva UPA-2 (for $299) more then I did the RMB-1575.

If you are looking to spend around $1k I would consider 3 x Emotiva UPA-1.

I am using a UPA-1 with my HTM3s with great success...

Cheers,

Stuart

[moosepapi]

Being new to all of this, with a 5.1 amp and bi-amping my r/l speakers, do I need to bi-amp my center channel speaker through my receiver then or is bi-amping a center channel a necessary thing to do? If so, am I going to need a 7.1 amp? Trying to figure out options and needs. I have an Onkyo 809. Running B&W 804s r/l and cmc2 center but hoping to find an HTM3s center. Am I gonna need two amps?

[stuofsci02]

Moosepapi,

Why do you want to passive bi-amp your mains?

Cheers,

Stuart

[htsteve]

Moosepapi,

Why do you want to passive bi-amp your mains?

Cheers,

Stuart

Moosepapi,

I also had the same question. I've tried this twice. And both times ended up happier with a powerful stereo amp.

Besides the extra cable cost, passive bi-amping still only delivers the original power level to each driver or driver set. 100 wpc to the bass will still be 100 wpc to the bass. A powerful stereo amp will have better current delivery, so all the drivers, especially the bass driver(s), will be fully driven. Soundstage (depth and width), dynamics and bass will be definitely improved.


Hope this helps.

[moosepapi]

I think I didn't ask the right question, or probably didn't express it correctly. I want to run my r/l and center through an amp, period and not my receiver amp. If an amp is 5 channel, I can't bi-amp three speakers, correct ? I was just wondering if I can't (provided I am looking at this correctly) then was wondering if I can bi-amp my center channel through my receiver. Hope I am looking at this right.

[stuofsci02]

I think I didn't ask the right question, or probably didn't express it correctly. I want to run my r/l and center through an amp, period and not my receiver amp. If an amp is 5 channel, I can't bi-amp three speakers, correct ? I was just wondering if I can't (provided I am looking at this correctly) then was wondering if I can bi-amp my center channel through my receiver. Hope I am looking at this right.

You are correct.. Bi-amping will take 2 channels per speaker. So for L/C/R you would need six channels. Although you could use a receiver channel + amp channel to biamp, I would strongly recommened against it.. You should use two identical amps for passive biamping.

But again, I am still not clear on why you would want to passive biamp any of your speakers. IMO you would be better of using all 5 channels for all 5 of your speakers and simplying using your receiver as a pre/pro.

Cheers!

[moosepapi]

Ok, I just hear so much about bi-amping and was not clear on how do do it correctly. so what I hear you saying is just using one set of wires for each speaker. If that is the case do I use the bridge on the speaker then or not. Just trying to figure out how that all works. So using one set of wires isn't passive amping then. That gives me the best results? Thank you for your patience with my questions.

[stuofsci02]

Hi Moosepapi,

If you run passive bi-amping you will need to remove the jumper on the speaker and run a cables from amp1 to the low speaker terminals, and another cable from amp2 to the high speaker terminals.

You can also bi-wire which is where you still remove the jumper at the speaker and run two sets of cables, but both sets of cables connect to the same amp. As an electrical engineer I have never found much merit in this.

Lastly, you can run a cable from a single amp to the speaker (high terminals or low), but you must leave the jumper installed. This would be a standard setup.

I would suggest starting with option 3. In my personal experience, non of the other options gave any gains that would warrant the extra equipment involved.

BTW, I still have the RMB-1565, so if you want me to test with my 804s let me know.

Cheers,

Stuart

[moosepapi]

Thanks Stuart, that would be great. I'd love to hear your opinion. Wondering if 5x100 is enough juice for my system.

I have been reading non-stop forums, info, etc on the pro's and con's of bi-wiring vs bi-amping. Then they talk about active and passive. I'm not a tech person much so I don't fully understand all they are saying. Boils down to this and opinions from anyone is appreciated. . . . I will be getting a 5-channel amp, probably either the Emotive XPA-5 or the Rotel 1575 as I have a chance to choose either. Should I just run one set of wires out from the amp to the speakers and use the bridge, or two sets of wires to all four posts? B&W supposedly recommends bi-wiring. I'm not a critical listener but I certainly appreciate great sound and just want to do the best I can have without hacking my speakers. I have to say I'm a bit confused. I just want to do justice to my B&W's. So the question is.. . . . You suggest option 3, running wires from a single amp to the woofer posts and leave the bridge. Do any others out there see that as the best way? Running my surrounds off my A/V receiver only if I am not running a single amp per speaker, i.e. bi-wiring.

[htsteve]

I just want to do justice to my B&W's. So the question is.. . . . You suggest option 3, running wires from a single amp to the woofer posts and leave the bridge. Do any others out there see that as the best way?

moosepapi,

All these options can be confusing. Stuart has done a good job explaining them.

The biggest impact will be in getting the external amp. Either the Emotive or the Rotel will add lots of current to your setup. The improvement will be immediate and obvious.

I would simply go with standard wiring and use your jumpers/bridge. You can experiment later with bi-wiring and shotgunning (two physical runs from one amp to the two terminals on the speaker).

Also, I'm partial to the Rotel. I used Rotel and B&W for many years with very good performance. The Rotel can really deliver the current. They have good synergy. Makes sense, as they have the same parent company.


Hope this helps.

[stuofsci02]

Thanks Stuart, that would be great. I'd love to hear your opinion. Wondering if 5x100 is enough juice for my system.

I have been reading non-stop forums, info, etc on the pro's and con's of bi-wiring vs bi-amping. Then they talk about active and passive. I'm not a tech person much so I don't fully understand all they are saying. Boils down to this and opinions from anyone is appreciated. . . . I will be getting a 5-channel amp, probably either the Emotive XPA-5 or the Rotel 1575 as I have a chance to choose either. Should I just run one set of wires out from the amp to the speakers and use the bridge, or two sets of wires to all four posts? B&W supposedly recommends bi-wiring. I'm not a critical listener but I certainly appreciate great sound and just want to do the best I can have without hacking my speakers. I have to say I'm a bit confused. I just want to do justice to my B&W's. So the question is.. . . . You suggest option 3, running wires from a single amp to the woofer posts and leave the bridge. Do any others out there see that as the best way? Running my surrounds off my A/V receiver only if I am not running a single amp per speaker, i.e. bi-wiring.

Moosepapi,

It might be a couple of days before I can give the 1565 a go..

IMO it is always easier to start simple and go from there.

Coming from and AVR, the new amp is going to make the biggest difference. The impact of Biwiring/Biamping etc. is going to be very very small relative to that new amp.. So spend the time auditioning the amps, because once you have made a decision on it, you are stuck. You can always try biwiring later. So don't focus on that now.

I am with HTsteve. Start with the basic wiring setup.

Now it is easy. Find an amp that you like. Remember that the 1565/1575 are class D amps. If you like the sound then great, but do compare to something that is Class A/B. In Rotel I would compare to a RB-1582 (I know this is only two channel, but this is just to hear the difference).

Cheers!

[ninja12]

Moosepapi,

It might be a couple of days before I can give the 1565 a go..

IMO it is always easier to start simple and go from there.

Coming from and AVR, the new amp is going to make the biggest difference. The impact of Biwiring/Biamping etc. is going to be very very small relative to that new amp.. So spend the time auditioning the amps, because once you have made a decision on it, you are stuck. You can always try biwiring later. So don't focus on that now.

I am with HTsteve. Start with the basic wiring setup.

Now it is easy. Find an amp that you like. Remember that the 1565/1575 are class D amps. If you like the sound then great, but do compare to something that is Class A/B. In Rotel I would compare to a RB-1582 (I know this is only two channel, but this is just to hear the difference).

Cheers!

Moosepapi,
+1 It's always best to start simple and go from there. I really think that you will be pretty satisfied with the simple setup.

[moosepapi]

Thank you guys, I really appreciate your input. I think you have made it much clearer to me as to what I need to do. You are right, start simple. That may be just all I need anyway. Excited to get the amp hooked up. Will have to decide on the Rotel or the Emotiva. Thank you again for your insight. Much appreciated.

[bigburner]

I am looking for a reasonable amp ($) for my 804s. Many of you have more experience with that than I do. I am currently looking at Rotel RMB-1565 for $1,100 and an ATI 1506 for the same. I want to stay around $1k. I would be bi-amping my center and r/l speakers and running my surrounds off my receiver.

If you are looking at Emotiva then the 5.1 amp is this one http://emotiva.com/xpa5.shtm and the stereo amp is this one http://emotiva.com/xpa2.shtm. Both are well under $1k.

Nigel.