[boclcown]

I just purchased a pair of 685s from a local dealer. He has some rotels that he'd like to sell me, but the cheapest he has is 40wpc at 599. I was told that the B&Ws like more power than less, though, so I've been looking at some other options.
 
One amp that is highly reccomended is the Onkyo A-9555. It's rated at 85wpc with 120w dynamic peak power at 8ohms. Given that the B&Ws have a recommended power handling of 25-100 watts, does this mean the Onkyo could blow the 685s at its 120 watt dynamic power? I know very little about matching wattage, and I trust the Head-Fi community, so I figured I'd ask you before I go prowling on the internet. 
 
Thanks guys. 

 

[eugenius]

harman kardon hk990 if you want a powerfull all-in-one with integrated DAC for a large room
 
sony ta-f501es if you want a small desktop amplifier with an integrated DAC for computer use
 
unison unico if you want smooth sound

 

[jilgiljongiljing]

Unless you are planning on turning the 9555 all the way up and go deaf in the process, the speakers will be fine. I would say go for the 9555, theres nothing in the 400$ range that can beat it IMO. If you move to 600-800$ range there are a few more options.

 

[batpig]

just because a speaker is rated up to 100 watts doesn't mean it will blow up if you feed it 101 or more.  That is just a broad rating of its handling capabilities, but it will not melt if there is a short dynamic peak that goes above 100 watts.  You really don't have to "match" an amp to the speaker like that, and in fact an amp rating for MORE power will do better because the real danger to your speakers is an underpowered amp clipping when you try to drive it too had.
 
also, just because an amp is rated at "120 watts" doesn't mean it will be constantly putting out 120 watts.  You only draw as much power as you need to achieve the volume you are using... which in most cases is actually much less than you think.
 
For example, those B&W 685's are rated at 88dB sensitivity; that means they will put out 88dB with ONE WATT of power.  It takes 10x as much power to gain 10dB of SPL, so they will be putting out 98dB with only 10 watts of power.  Even subtracted some SPL for listening distance, if you actually fed them 100 watts they would be ear-splitting loud; you almost certainly will never need that much power unless you were trying to drive them to huge volumes in large room.
 
That's why for a 2-ch setup in a medium-sized room a 40-50 watt integrated amp is often plenty of power.  Remember also that a Rotel will be rated much more conservatively than a lot of other brands... those "40 watts" on the Rotel are probably a lot more REAL power than a little sh!tbox $299 Sony or Yamaha home theater receiver which advertises "110 watts x 5 channels!".

 

[JerryLove]

http://emotiva.com/upa2.shtm

 

[boclcown]

I went ahead and purchased the A-9555. I'll let everyone know how it worked out. 
 
Is there anything I should keep in mind when hooking up the speakers to the amp? Or is it as simple as connecting the wires and BAM?

 

[jilgiljongiljing]

Yep simple as that. The 9555 has a pure direct mode (button on the front of the amp) that bypasses the tone controls for a cleaner signal path, IMO it sounds very good in that mode.
 
Also worth considering is swapping out the power cable on it since it is detachable. The fuse upgrade is one that has some discussions, but I for one haven't tried it and don't plan to either. I dont see a fuse being worth 50$. I'd rather put that towards music or other components.

 

[jilgiljongiljing]

 
Quote:

http://emotiva.com/upa2.shtm

 
Thats a power amp. You'll need a comparable pre-amp to use it, and a decent one to make the most of it.

 

[Lenni]

 
Quote:

I went ahead and purchased the A-9555. I'll let everyone know how it worked out. 
 
Is there anything I should keep in mind when hooking up the speakers to the amp? Or is it as simple as connecting the wires and BAM?

how much did you pay for, if I may ask? another good amp for the 685s would have been the Yamaha A-S500
 
the A-9555 don't take banana plugs, in case you didn't know.

 

[jilgiljongiljing]

Quote:

 
Quote:

I went ahead and purchased the A-9555. I'll let everyone know how it worked out. 
 
Is there anything I should keep in mind when hooking up the speakers to the amp? Or is it as simple as connecting the wires and BAM?

how much did you pay for, if I may ask? another good amp for the 685s would have been the Yamaha A-S500
 
the A-9555 don't take banana plugs, in case you didn't know.

Uh WRONG. The A-9555 absolutely takes banana plugs. I have them connected with Monster Banana plugs right now. I don't know where you get your info from.

 

[Lenni]

I used to have the 9555. I could only fit either bare wires or spades. it didn't have space for banana plugs. I don't know how you fit yours

 

[jilgiljongiljing]

I just plug it in the back like on any other amp with binding posts. Remove the caps if there are any, and shove it in.  I dont know man, its like anything else, nothing different.

 

[Lenni]

ok, I didn't know the caps could be removed...lol (silly me!). why would Onkyo put caps on the posts I'd like to know. I've never seen it on other amps that I know of. do you have a small pic of it by any chance? I'm curious now...

 

[jilgiljongiljing]

Heh, it happens
 
I dont remember if the 9555 came with caps, I remember my Martin Logan, and Sonus Faber's came with caps (if I remember the Polk Rti4 came with caps as well). I don't have pics right now though, never really taken pics of the amp. But yeah in most cases, you just use a small screw driver and pop it off. I guess it gives a cleaner look with the caps on in case you are not using banana plugs :S
 
not sure if there is any other benefit.

 

[Uncle Erik]

With the banana plugs, you do not have to remove the caps. Unscrew the caps about as far out as they go. Stick the banana plug down the hole in the middle of the cap, then tighten the plug. It will clamp down on the banana plug and make a secure connection.