Is a sonic improvment if I use a stereo pre instead of surround processor?

[dixon]

Hi guys,
I nees some advice,opinions here.So if I have a dedicated 2 channel pre(stereo) like RC 1070 or 1090 instead of use rotel rsp 1068 for 2 channel,I will have a better sound in stereo?
Second question:Can be integraded the stereo pre(RC-1070 or 1090)in a HT setup,so when listen DD or DTS,etc,bypass the stereo pre?
Thanks,any help are much apreciatte,
Dixon
Ps. My setup:
rotel rb 1080
rotel rmb 1075
rotel rsp 1068
denon ar 1650 cd
denon dvd 2900
sonus faber speakers
monster power HT 3600

[Eiffel]

I am not familiar with the RC 10x0 preamps, but a very good 2 channel stereo preamp does make a difference (I'm basing this on my setup which includes a Rotel RSX-1055, RB-1080 and Audio Research LS15/VT100MkII driving a pair of Totem Mani-2s for stereo applications).

For this setup to work, you have to connect the stereo outs of your surround processor to one of the inputs of the stereo preamp (Not the opposite, as you'll introduce a weaker link in the stereo chain). Some preamps have a surround processor bypass function (which bypasses the preamp volume control when activated). If this is not the case, you have to make sure you set the preamp volume to a predetermined level each time you want to listen to multichannel sound (so that the L & R volume level is consistent with the C, RL, RC, etc. channels).

For the record, I've tried an alternative approach: connect my preamp via balanced connection, and the processor via RCA connections... so that I could use the small switch at the rear of the 1080 to listen to either source. Unfortunately, switching to balanced mode doesn't completely disable the RCA inputs, and this doesn't sound as good as a result)

I do find the difference pretty noticeable for stereo listening (more than switching amps, which tells me that the 1080 is a bargain), but you have to keep in mind that I'm comparing the pre-amp section of a 1055 with the preamp section of a fairly expensive stereo only unit. With a 1098 I would expect that the gap will be smaller.(the 1098 is also newer than the 1070/90 which many make a difference).

The best way to reach a decision is to listen to both setups and decide what you prefer

[DrBoom]

What a coincidence, I'm planning on doing exactly the same.

The reason is that I listen to music about 90% of the time, and if I'm lucky I can catch 1 movie every 2 weeks.
And I've never been really happy with the stereo performance of my RSP1098 (or even my Parasound C2 for that matter, shows you how critical I am).
So in an attempt to see how much difference a preamp makes, I tried the following experiment.
My Parasound HCA2205AT poweramp has variable gain inputs that can be adjusted at the rear of the amp, so don't try this with an amp that has no variable inputs, you'll blow something up for sure !!
I connected my RCD1072 cd player directly to the HCA2205's inputs, and turned the gain all the way down.
The I turned on both machines, and slowly adjusted the gain untill it was loud enough, which was like the 10 o'clock position of the gain, so imagine what happens if you set it full throttle...
The difference was absolutely staggering, bass was incredibly tight, but even more important the mids completely cleared up and the highs became much, much more extended.
I've been running the RSP1098 in analog bypass mode since I got the CD player, so you would think that because it acts only as a volume control in that mode, the difference wouldn't be too big.
WRONG !
Bass has never been the 1098's strong point (or Rotel's for that matter), so that part is an incredible step forward.
The midrange I always found good, but too much of it at some times.
And the highs sounded very sharp and sibilant, which until now I had blamed the RCD1072 for but that went away as well without the 1098 in the chain.
So for me it's very very clear that a dedicated stereo preamp with a "theatre throughput" or "SSP" mode is the way to go if you want to combine high-end stereo with HT.
I'm looking into such preamps at the moment, but they don't come cheap.
Classé's new CP500 has this function, Mark Levinson 326, Accuphase C245 and maybe some others do as well but I've yet to find them.
If you don't have a good enough power amp for pure stereo, you can also take the integrated amp route, there are a number of integrated amps that can be used as a power amp for the front channels in HT as well.
Once again Classé, the new CAP2100 and the (discontinued) CAP151, Krell integrateds with Theatre Throughput, and several others.
What's important for integrated amps in this situation, is that you can select the Theatre mode from the front of the unit.
Many other integrateds have the function, but many of the use a switch at the rear to do this, not very handy.

I'll definately be adding a dedicated stereo section to my setup in the near future, the difference is well worth the price if you listen to stereo a lot. :T

[soundhound]

In my situation YES, I purchased an RC-1070 to replace the 2 channel capabilities of the RSX-1055, and it was night and day. I had an old ADC DD-A4X in the closet that I ran both the 1070 outputs (cd in) and 1055 front outputs (tape in) into. It has pass through for both "main and "tape mon" inputs to output so power wasn't even needed and I can rest assured I have the best path possible. I tried piping it all through the 1070 and found the need to mess with the controls depending on source quite unpleasant. Any old processor with tape monitor/ source should net the same results. Its simple, I want to listen to music, on comes the 1070, the source button on ADC goes on and manually power my RMB-1075 (actively using front mains only) and wha-la, sweet 2 channel. Crydom makes optically isolated relays with a current draw of 2.5 ma each so a person could easily build a switcher to run off of the sources 12vdc triggers to automate the process. I purchased the relays for $15 USD and was going to go this route until I found the old processor (while looking for a case to put the home-made one in). Anyway, back to the topic, I had heard the RSP-1068 in a demo and I dont believe I would be searching for a dedicated if I owned one. That thing was a heck of a machine, superb 2 channel, as well as 7.1 capabilities. If I owned one of those I would be putting money into "Tunes", albeit, albums, dvd's, cd's as I would be surprised if one would notice any sonic gain between any of Rotels pre-pro and straight 2 channel pre only. Just my .02, Bob

[dixon]

Thanks for the input guys I would like more opinions!
Thanks in advance,
dixon

[will1066]

Dr. Boom, I'm surprised you aren't happy with the 1098's plain stereo performance. I believe the industry classifies preamps with a theater pass-through as multichannel preamps. I think bel canto makes one. But I think this area is a small niche, as not too many brands make such products, though I wish more would. And they're expensive, like traditional high-end two-channel pres.

[JonLeach]

This is from a thread i started earlier, no one has answered so i thought i would paste it in here as its almost the same topic,


Does a RSP1066 make a good stereo pre



Hi Guys,

i have been trying to extract the most out of my 1066/1080 with Dynaudio42's for stereo. the setup is meridian 606 dac with various inputs going in the CD input on the 1066. it sound sweet but i was wondering if i spent a little money can i get a 2nd hand pre that would do a better job, i have shifted towards music 75% from adding the meridian DAC.

What are the implications to adding another PRE


Jon


P.S. don't have to be a Rotel pre.

[will1066]

This is hearsay, but the 1066 is supposed to be competitive with traditional pres in the same price area. The RSP-1098 is said to be significantly better. I too am debating getting a higher-grade traditional pre or a higher-grade processor. I'm assuming you would keep the 1066 in your system if you go toward a traditional pre. The implication is you'll improve your music listening but perhaps hurt your HT listening because you would add a second preamp stage into the system. Output from the 1066 would have to pass through the new preamp before reaching the amp stage (RB-1080).

[JonLeach]

hi Will,

i take it you also have a 1066 judging by your UserCP. i have just been discussing it with a friend who is stereo only, Naim gear and it sounds so good, i will hopefully be tryng my CD/DAC on his system to see if there is anything more to give.

are you sure its rated as a £1000 pre, i would have thought £500 at the very most. if it compares well than i may think about other options.........don't know what they would be yet though.

Jon

[aarsoe]

Well - got intrigued by this thread, so I did the only thing possible...

Purchased two Krell preamps, a KAV250P and the KRC-3 that both allows for a surround pass through. The idea was to keep the one I liked the most and sell the other again.
Anaway - conclusion? Whole different thing. All of a sudden my stereo is fantastic. I just love it. There is actually more surround in my KRC-3 than in my Rotel 1066 - If you catch my meaning..
I am a happy camper!!

[DrBoom]

Ah, another converted soul

I'm still contemplating on what to do, either replacing the RSP1098 with a Classé SSP300 or Primare SP31 (or something like it) and using that for stereo as well, or keeping the RSP1098 (for the time being) and adding a stereo preamp with theatre throughput like Krell/Classé CP500/Primare PRE30/...
I would prefer to keep it as simple as possible, so I'd prefer to just find a processor who's stereo performance I can live with.
But that's not going to be easy since I already had a Parasound C2 and that didn't cut the cheese well enough either, though it was substantially better I must say.
As far as affordable pre's with HT bypass go, the Primare PRE30 is very very tempting, costs around €1800 new and it's a very respected brand.
They're also supposed to have a really good HT processor with excellent stereo bypass mode, namely the SP31, retailing for approx €3200 which is less than the RSP1098 actually, but has less options and settings.
I'm going to have a listen at both as soon as I get the chance, but the nearest dealer is like 100 km from here.
For people in the US and Australia that might be like driving to the supermarket or your neighbours house, but over here it's the other side of the country :B

[aarsoe]

DrBoom

I agree on the "keep things simple" princip - however I have yet to come across a processor that even comes close to the two channel performance of my new Krell. To be honest, I dont care any longer, as the theather passthrough option is just SO right for my use. It even allow me to keep my power amps for the rear, center and back channels off, when listening to stereo (I could also do that before, but it meant going over there and turning it on and off each time).
Another benefit is the balanced input and outputs for power amps, that the Rotel does not offer.
Even my dear wife, sat down with me yesterday evening, and said: I have never heard your gear like this before, its like hearing the music for the first time - and not just a reproduction..

Downside? Well, told one of my friends, who immidiatly said: "Well, wonder how good it will be if you also get the krell power amps to go with it, and maybe also the cd player...!"
May he rot in hell for that - been thinking about it ever since..