oppo's volume control

From what I've read from the main Oppo experts on AVSForums is that the Oppo always sounds better with a pre-amp.

I was looking to upgrade my amp and excluded looking at power amps

Just to clarify I was quoting Bob Pariseau who appears to be something of an expert on the capabilities of the Oppo 105 and he basically said it always sounded better with a preamp.

For me personally as well I worry about the default setting that can revert the Oppo back to full volume and if you are just using a power amp....ouch.

I really like my Oppo 105 by the way.

Moving the debate on....although personally I wouldn't put anything direct into a power amp other than an Oppo 105-that's the machine designed for optimum stereo playback....I have had the chance now to try the Oppo in this mode.

I've upgrade my amp to a Rega Osiris which has the ability to take a direct input.

The first thing I noticed due to the gain differences is that at volume level 1 on the Oppo is pretty loud as a starting point (0 is mute) although I've ordered some attenuators to see how that works.

What I do prefer is that the Oppo gives a much tighter volume control that the Osiris itself-that 0.5db increase is nice.

I haven't done this particularly analytically and I don't have a sound meter but I have a quick A/B using Beck's Sea Change (HDCD) and Radiohead's OK Computer.

To me the most obvious thing is that going in direct has a much more closed in sound-my speakers neither project the detail or 3D sound staging. It is noticeably different and possibly the change in presentation (I've only had the amp 4 days and only listened normally during that time) is off putting and I'm missing some positives but my gut reaction off the bat etc etc is that in my system with my amp going direct seems inferior and noticeably so.

I will return to this in more detail later as I do prefer the volume control steps via the Oppo.

Runnin the Direct channel on the Osiris is RCA -indeed it only has one XLR input.

As it is I haven't even tried XLR-as my current cables were a tad short due to the Osiris having it's XLR at the far end of things.

I have an XLR cable due along with a set of attenuators for both set ups-RCA and XLR just to see how they work out. I was a tad worried about the extra volume on the XLR so I'm buying a pair just to see.

The Osiris has been reviewed as performing better on XLR and my dealer reckons this is also the case so we will see.

Attenuators are relatively cheap-like yourself I have some concerns but I suppose you trust your ears-they can come back out.

I think whatever the Rega Orisis does in direct mode badly inhibits the sound-it really doesn't sound right.

Of course this is an integrated amplifier so it is probably not comparable to what might happen directly to a power amp.

Just an update on optimising my system. My Rega went back for a minor repair-a known fault on the On switch-it was jammed in-now back and fine.

The combination of the Proac's and the Osiris is quite potent-it can get loud very quickly with the Oppo set at 100 on the volume output. The Osiris has a passive pre.

Using the variable option I found an output of around 75-80 on the Oppo gave me great sound in my set up with a bit of leverage on the amp control too-the fine notches on the Oppo can adjust the volume very nicely.

I asked on the AVS Forum about any negative effect in doing this-one poster suggested that below a 75 output the noise floor is increased but it is not particularly noticeable-from 75-100 he said it has no effect. Not sure how accurate that is.

But going direct from the Oppo into the direct option on the Osiris even with attenuators you can not even get close to 75-so possibly that has had an impact on the noticeably inferior sound I hear.

I don't know how accurate this might be-it would be interesting to hear what output setting those using the Oppo direct in a power amp are using.

George I'm not following you the Osiris is an integrated amp that uses a passive pre-it also has a direct input to allow the Osiris to be used in say a home hi-fi set up. I've maybe not explained it correctly.

As I understand it, there is not bit stripping on the 105 DAC's.

For whatever reason when I go direct into the Osiris with the Oppo the sound is noticeably poorer-it doesn't sound transparent at all quite the opposite.