Please help with upgrade question!!! RSX-1056 & RB-1070

[theMaximus]

I currently have RSX-1056 driving B&W 704 speakers (along with HTM7 center, DM 601 S3 surrounds, and ASW-600 sub). Not that I'm unhappy with 75W per channel, but I'm starting to wonder if getting a RB-1070 (2-channel amp with 130W/channel) would greatly improve my system. My local dealer does not stock RB-1070 and therefore, I cannot actually audition. Does anyone have a similar upgrade experiences to share with me? Your input is greatly appreciated.

[Aussie Geoff]

Hi,

It all depends on what you are seeking from the improvement with a better amplifier - some things are deliverable with amplification, others not. Lets us know and we can help more, but for now, here are some ideas:

• The B&W 704 loves more power / current. The RB-1070 is much higher current into low impedances than the receiver you have so will help. If you want to be really sure, get the RB-1080 (Stereophile rate it as the best amp under US $2000). Personally I'd get one (US $300 more) as it will remove any doubts as to the amplifier and the 704s and will last you through several upgrades.
• Bi-wiring - the B&W 704 (like all the 700 and 800 series) are made for bi-wiring with high quality speaker cable. Your dealer can help there, as can forum sponsor www.catcable.com (and others )
• Better interconnects. For example as you will see HERE I (and now several others) have been simply blown away by the extra detail / clarity form the Cat Cable Silver Coax for the digital link for the DVD and CD player.
• Very careful set-up of speaker distances and levels - measuring the speaker distances and using a sound pressure level meter to set the speaker levels accurately.
• Careful speaker placement - for example if at all possible have the 704s away from the wall and the corner and don't have the rear (and front if you can) foam plug in)

Now that I’ve told you that – if you are playing reasonably loud and what you are after is tighter more controlled mid bass and more open midrange – the extra power from the RB-1070 will help quite a bit and the RB-1080 more....

Geoff

[Azeke]

I would upgrade to the RB-1080 to remove any power doubts. I also struggled with upgrading my fronts with a 2 channel power amp, I eventually upgraded to the RB-1080 (after the RB-1050), and I am not regretting my decision. It's better to have too much power that not enough, that's my philosophy :T .

Also remember amps, don't alter very much in design, so therefore you retain them longer.

Hope this helps,

Azeke

[theMaximus]

Thanks for your insights.

I'm using AudioQuest GR8 bi-wires for my speakers and Audio Magic Xstream digital cable (silver cable) for my Cambridge Audio Azur 540D DVD Player (I'm also using Cambridge Audio Azur 540C CD Player with Monster Cable M 550i RCA interconnects). As far as speaker placement is concerned, I'm still experimenting with different locations. Your input on amplifier power was very helpful. I suspected that since minimum recommended power for B&W 704 is 50W, 75W/channel power output from RSX-1056 was slightly on the low side. Even though Rotel's power output is underrated, I thought healthy 130W/channel from RB-1070 would improve the system performance. Thanks for your insights.

[Aussie Geoff]

A couple more ideas..

theMaximus,

Seeing your other equipment, which is clearly carefully chosen and of high quality - you won't go wrong with the RB-1080...

I have two other suggestions to try for your CD player:

• If you listen to anything other than pure stereo bypass on the CD (i.e. no subwoofer, just 2 speakers) the RSX-1056 (like virtually all receivers and processors) will be redigitising the analogue sound, processing digitally it for bass, or PL IIx or whatever, and then converting to analogue again. There is extra two losses of quality here (one for the conversion to digital and then one back again). So try a pure coax digital connection as well – that way the conversion to analogue will only be done once in the RSX-1056. You can even hook this up to a different input so that one device is the CD Analogue, the other is the CD Digital. You seem to have a reasonable coax for your DVD player - so you may want to try this on your CD to test the effect and buy another one if you like it. I have had lots of people much happier with this.
• Upgrading the Analogue Cables to the CD from the Monster Cables, You could stick with some good products from Audio Magic or Audioquest since you seem to like these existing brands and both have good reputations....

Hope that helps

PS -You still haven't said what you are looking to improve with the B&W 704's sound.

Geoff

[theMaximus]

First of all, I'm looking to get cleaner and more detailed high/mid and tighter bass from my 704s. I'm hoping that better design and transformers of dedicated 2-Channel amp can provide me with what I'm looking for. I would really want to get 1080, but it is a little out of my price range. I wouldn't mind at all going over the recommended power range of 704 (50~150W), (in fact 200W/channel would probably be about ideal power output), but I'm hoping 130W/channel of 1070 would be a good improvement over my current set-up and provide better "bang for the buck" than 1080. Correct me if you think I'm wrong.

Also, I have very minor hiss from my 1056 like many people complained in the forum. I cannnot hear it from more than 3 or 4 feet away from the tweeters, which is really a non-issue since I sit at least 12 feet away from my speakers. However, knowing that the hiss is there kind of bugs me a little. I doubt if adding a power amp, thus using the receiver as preamp in 2-channel mode, is going to eliminate the hiss, but maybe I'll get lucky.

As for listening to music in 2-channel, I use the analog connection from my CD player (I love the sound of new Wolfson DAC on Cambridge Audio!) to my receiver and setting the receiver in 2-channel analog bypass mode. But, I'll try your suggestion about didital connection and see how I like it. Thanks. :T

[Aussie Geoff]

theMaximus,

I'm looking to get cleaner and more detailed high/mid and tighter bass from my 704s.

Excellent this is exactly the effect that a high current power amplifier has on the B&W 704 -(and other B&W 700 and 800 series speaker). Many people have noticed it.

I'm hoping 130W/channel of 1070 would be a good improvement over my current set-up and provide better "bang for the buck" than 1080. Correct me if you think I'm wrong.

There's no doubt it will help since it will both remove strain from the RSX-1056 and allow a similar sized power supply to drive the 704s. However the issue here is "will it help enough" - really you should listen. But if you can't - I can tell you that 200w will help more. Here’s why (netted out):

The higher end B&W speakers (like 99% of high end speakers) have complex crossovers to optimise performance (e.g. the 2 ½ way crossover in the 704). These crossovers, combined with a bass reflex enclosure create wildly varying impedance curves. These very often vary from 2-3 ohms to 40 or more Ohms over the 20Hz to 200 Hz range. For the speaker to provide the same volume at across this frequency the amplifier needs to follow this with changed in power that are proportional (e.g. going from 8 ohms to 4 ohms needs doubling in power and current, while going from 8 ohm to 2 ohms needs 4 times the power. Given that a speaker will be playing multiple frequencies at once with music (e.g. a 30Hz note with 60 Hz and 120 Hz harmonics) this is very demanding on the amplifier. What we are after is as much power and current as possible into as low impedances to deal with the frequency / impedance changes

In terms of “bang for the buck isn’t the 1080 only US $300 more than the 1070 – surely better value?

I doubt if adding a power amp, thus using the receiver as preamp in 2-channel mode, is going to eliminate the hiss, but maybe I'll get lucky.

You are probably right with this – but I have personally found a really good power filter to be excellent at reducing hiss.

Re Analogue and CD
If you are running bypass and no subwoofer then you will be getting the CD Players DACs so that is fine (they will be better than the RSX-1056) and probably the best stereo sound you can get (other than changing the interconnects). I'd still try the second connection for digital so you can use DPL IIx Music, or 5 channel stereo etc for parties or for when the mood hits you...

Geoff

[aud19]

I think I can help you with the 1070/1080 toss up. Ask yourself this:

Do you plan to continually add to and update this system over the years such as adding a seperate 5-channel amp and seperate pre/pro? Or are you more likely using this equipment for a while until you can afford to do a whole new system and either sell this existing equipment or move it to a secondary system?

If it's yes to the first question, go for the 1080 it will save you money in the long term as you'll just want to update the 1070 later anyways.

If it's yes to the second question, go for the 1070. You plan on moving on in the future anyway so save the few hundred bucks while still getting a boost in performance. Or spend that few hundred bucks on cables/power filter etc.

Jason

[Bob Knarly]

Well I can tell you an amp is NOT going to help the hiss.I have several amps B&K,Hafler and Parasound(tried em all) and they don't make it worse or better,it still hisses about the same.An amp will be an improvement,and 200 watts would be great.The 1056(for an avr)really does have good power but either of my 2 ch amps sound way better.I would go for a used 1080 v a new 1070,just my opinion.

[theMaximus]

I got RB-1070!!

I had to drive a couple of hours but I finally ended up purchasing a new RB-1070. I did look for a used 1080 like some people suggested but could not find one in silver and prices for used 1080s. Dealer I went to gave me a pretty good deal on 1070 so I decided to get it. I've noticed fairly good improvement for over my Rotel RSX-1056 receiver in 2-channel mode and pretty happy with my purchase. I'll most likely stick with my current set up for a while.

I also replaced my Monster Cable M550i interconnects with Ecosse Composer interconnects but didn't notice any significant difference. I know many people generally hate Monster Cable (me being one of them), but I originally purchased M550i since they got some fabulous reviews by Home Theater magazine, and I think they were pretty much right. Monster Cable make a lot of crappy cables, but I guess M550i was one of rare exceptions.

If anyone wants to buy interconnects check out

http://www.fsaudioweb.com

The owner's name is Frank and he gave me really good discounts.

[Aussie Geoff]

theMaximus,

Glad to see you are happy with the purchase. Thanls for letting us know that it worked for your. Hopefully the amp is clearing up some of that bass / mid bass issue you had.

The best bit is (assuming it is new) you will probably find after somewhere from a week to a month the amp will suddenly get better again...

Enjoy!

Geoff

[DelRay]

Glad to hear that the 1070 is working out. I'm still waiting for mine to come in. I will be pairing it with my 1075. and will be used to drive my fronts. I agree about the availability of used rotel equipment. It doesn't come up very often and when it does it seems like it commands a high price. I believe that this is a good thing though. Shows the quality of the gear. Enjoy your new stuff. :T

[Azeke]

Congratulations with your new Rotel purchase. After a couple of weeks of break-in it will really sound great.

Keep up posted.

Regards,

Azeke

[sdecker]

I use a RB-1070 with a RSX-1055 and am very happy with the improvment with 2 channel listening.

I decided to go with the 1070 over the 1080 because I use Klipsch speakers and the extra watts werent necessary. The 1070 seems to drive my mains with a little more authority compared to the 1055's amps.

Good choice with the 1070, I'm sure you will be happy with it. :T

Earle

[aud19]

Congrats !! arty:

Jason