Help!

nnguyen29

My current system consist of HK AVR-525, RTi150s (front), CSi40 (center), and RTi38s (surround). Although (to me) I seem to be satisfied with the way the RTi150s sound in 2 channel mode (HK AVR-525 puts out 90 watts per channel in 2-channel mode), I have this itch to buy a 2-channel amp to drive the RTi150s - for now using the pre-outs (front channels) of the HK-525.

I am thinking of getting a NAD C272 (150 watts x 2) power amp. My questions to all the polkies out there are:

1) Will the NAD C272 do a better job than the HK-525?
2) Is this worth doing?

BTW, I recently had a chance to try out a pair of the NuForce Ref 8b (mono amp which puts out 100 watts per channel). After a week of doing A/B comparison between the HK-525 vs NuForce Ref 8b driving the RTi150s (in 2-channel mode without subwoofer), neither I or my wife could tell the difference. I could not believe that the HK-525 sound so good in 2-channel mode.

One thing I need to mention is that I recently had a dedicated 20-amp circuit put in for my HT room and I think that this is what makes the HK-525 sound so good (as compare to previously when I had all my components connect to the old 15-amp circuit).

Thank you very much for reading my post!

Toxis

1) yes.
2) yes.

Early B.

1. Maybe, maybe not.
2. Depends.

The only way you're gonna know is to try it. Just make sure you can return the NAD or resell it for what you paid if you determine that it's not worth it.

nnguyen29

Earl,

Can you please elaborate on your answers?

Thanks!
-Ben

nnguyen29

Toxi,

Can you also elaborate on your answers?

Thanks!

cfrizz

I think if you really want to see a discernable difference you should get an amp that starts at 200 wpc & up.

nnguyen29

My gut feelings tell me the same thing (that you adviced)...

I think I will pass this up and go for something that is much more powerful...

Thanks!

Toxis

I have found that just adding a seperate power amp can and will help the sound dynamics and sound stage. I "downgraded" from a 120w receiver to a 100w amp and the improvements were amazing. Before I got my 100w amp, I had a 2ch Rotel amp at about 120w and it was a big difference from that and the AVR. Then when I got a 5ch amp with "less power" the sound only got better yet. If you tried it with that one amp and didn't hear anything different, maybe 1. you weren't listening for the right things or 2. you were expecting an increase in volume instead of dynamics.

Early B.

nnguyen29 wrote:

Earl,

Can you please elaborate on your answers?

Thanks!
-Ben

OK.

Like everything else in audio, it's subjective. There are also too many other variables to consider such as the size of your room, the size of your wallet, WAF, the quality of your source, etc.

I used to have separate amps on all channels and it sounded much better than a receiver, but for me, it wasn't worth the money. Through experimentation, I realized I could achieve a similar sound by upgrading components, especially speakers and cables, at a lower net cost.

nnguyen29

Toxis,

When I did an A/B comparison between the HK-525 vs. the Nuforce amps, I was not looking for more volume. I was looking to see if the bass was more defined, the imaging was better, and clarity was better. The material I used were songs that I have listened to many times and very familiar with. When I did not see any improvements from the NuForce amps, I decided to not go with them. These amps cost $1,800 a pair new and my friend was going to sell them to me for $760. After I returned the amps to my friend, he listed it on Audiogon for $800 and they were sold within a few hours!

I would appreciate any more comments from you.

Thanks!
-Ben

Toxis

do you have a seperate sub? Is your receiver set to give you full range to the mains?

nnguyen29

I do have a sub (Hsu VTF-2). My receiver is set to send LFE signal to both the sub and mains (when they are set as Large).

However, during my A/B comparison I set the sub to no sub (on my H/K). The RTi150s do go pretty low and the bass is pretty good in this 2-channel (without sub) music only!

Sherardp

seperates are the way to go, although I would probably drive them with a little more. Look into outlaw they are good bang for the buck amps. Good sound too. And since youre looking into driving just your mains, look at the M2200 monoblocks :cool:

nnguyen29

Sherardp,

Do you think the Outlaw M2200 will mate well with my RTi150?

Do you think 2 M2200s are good enough or do you think 4 M2200s (for bi-amping )?

Thanks!
-Ben

Sherardp

I would use the receiver (HK AVR) and go with two M2200s, then bi-amp. Im running my Rti12s on a Sony 7100ES (170wpcx7) and two Outlaw M2200 in a bi amp setup, the sound is amazing. Even if you went with just two M2200's you would notice a difference. And yes I think they would mate very well.

nnguyen29

"I would use the receiver (HK AVR) and go with two M2200s, then bi-amp. Im running my Rti12s on a Sony 7100ES (170wpcx7) and two Outlaw M2200 in a bi amp setup, the sound is amazing. Even if you went with just two M2200's you would notice a difference."

How do you bi-amp with just 2 M2200? Please explain to me.

Thanks!
-Ben

Sherardp

nnguyen29 wrote:

"
How do you bi-amp with just 2 M2200? Please explain to me.

Thanks!
-Ben

You remove the jumpers on your speakers, from the HK AVR run a good quality RCA cable (audio Interconnect) from the front left/right preouts located on the back of your AVR into the input of the M2200s. From there connect the avr to the top speakers post ( usually your highs) and the M2200s to the bottom set of speakers post( usually the lows) and of course use good quality speaker cable, doesnt have to cost you a million bucks but I went with 12 awg Monster cable. Sit back and enjoy from there.

Outlaw M2200s are nice, very thin in size but has good weight to them so you know they are quality. Allot of the guys here use them and have used them, if this is your first time with seperates as it is me, you will enjoy them. Plus you can order them, try them out and if you dont like them you can send them back for money back in a certain number of days (call to find out exact number), Im more than happy with mine, and they will sure as heck drive your 150s and then some.

nnguyen29

Sherardp,

Thank you very much for all your input!

Now I have to go convince the wife to get these M2200s for my birthday (coming up in August)

Sherardp

No problem guy, enjoy and welcome to the world of seperates. I just got into this also, and did my homework like you are. I think Outlaw may even offer free shipping, you can ask though, their customer support is excellent. Your system will sound awesome after you have them installed.

nnguyen29

Sherardp,

I just checked the Outlaw web site and among the special offers on M2200 is $624 for 2 with free ground shipping ($325 + shipping if you buy only one).
Not too bad price for 2 200-watt mono amps!

Regarding your bi-amping using both the Sony receiver and the M2200: I thought that when bi-amping, you should use the same type of amps?
Do the lows & highs sound seemless?

Did you do an A/B comparison for the following:
1) Sony + M2200s driving the RTi12s
2) M2200s driving the RTi12s

Thanks!
-Ben

Sherardp

My setup does sound seamless in 2 channel mode. The highs are nice and crisp and the bass is tight. I had my sony driving the 12s for 2 days they did sound good, however I knew I wasnt getting the most out of them, I had the M2200s on hand so I decided to just go ahead and add them in, and wow, a huge difference, I could tell the outlaws were in place because the 12s seemed to have open up even more. I imagine your 150s will do the same being that they are some close in specs to the 12s. As for just the M2200s driving the 12s I dont think I'll go that route, since I want maximum power driving these bad boys.

You can do a search on google for M2200 or M200(same amp minus the balanced XLR input) and read in depth reviews. I did the same thing before I bought mine also. I have never heard any humming, noise out of mine etc. They are excellent, try em out, you wont second guess your decision.

Sherardp

Just got done auditioning my 12s again. Breathless. Love em. Best investment I made with this setup.

nnguyen29

Sherardp,

One more question: how do you calibrate your mains for this bi-amping configuration (Sony + Outlaw 2200)?

Thanks!

Sherardp

You do it the same way as you normally would, I calibrate reference level by turning my receivers main volume to 00db, from there I run the test tones of the receiver then adjust my settings to achieve 75db on all 7 channels, in your case it maybe 5/6/or 7 channels as well. With the amps installed in your system you may need to lower the settings on the fronts but just adjust accordingly and you will be fine. For the sub(LFE) turn your volume (gain control knob on the sub itself) to about 1/3 or 1/4 the way. Then adjust the settings in your receiver settings to again achieve 75db, I run my sub a little hot so I run it up to about 78( its an SVS PB12 PLus 2 :eek: ) and thats it man. Very simple, you can do it, no worries.

I dont know if you have one but I use the Radioshack SPL meter, analog version,to cal my setup.

nnguyen29

Sherardp,

Yes, I do have a Radio Shack SPL.

Thanks!

All,

What speaker cables, interconnects and power cable do you recommend?

Thanks!

Sherardp

check out audioquest, bluejean, cablestogo, cobalt, bettercables, and best deal cables, all of these are good quality cables, monster isnt bad either, I just monster speaker cable. But check out some of these mentioned and buy the ones u like and of course ones that wont require you to refinance your place.