Newbe Help what AV amp

Hi, almost picked up ATC SCM40s for my front 2 channel , my source is a Denon 4010UD bluray player, I tried the ATC SIA 2-150 amp.
The sound was fantastic with CDs playing direct mode but the minute I tried a Concert DVD or a concert Bluray the sound was awful..
Is it a problem with the connection or do I need a AV Amp.
Anyone tried Primares with. ATCs or should i stick to ATC amps?
A Concert DVD should work just fine provided you select Stereo!

Sound quality of live concerts is often not up to par though.

If you want to play 5.1 through a stereo then I am afraid you need to "downmix" which might or might not be an option on your Blu-ray player.

If you play 5.1 through the stereo with just L and R channel outputs connected to your stereo amp then you will be missing much of the vocals (center channel) and the bass (0.1 subwoofer channel)
Thks Shadorne , Strangly the same videos sound good coming out of the TVs stereo speakers.
The dvd also has 2 channel stereo option n I had chosen that, but like u said is it because of the missing centre n subwoofer channel?
I guess i goofed up the connections.
Manual for the Denon if it's the correct one.[]
I'm not that savvy when it comes to all the new multi-channel audio. I'm a two channel guy. If nobody that is savvy on this chimes in, try the 2ch (two channel) setting on your Denon. Its on page 24(pdf shows 28) in you manual. This may work, but I don't know if it will have an affect on the output for other things you play, but you could always change it back. If this doesn't work, maybe you could put a "Y" on the two channel output to feed both your tv and stereo.[]
Sorry, the link was supposed to be for the manual.[]
I should have mentioned, the Y connector works sometimes, but not always with the best sound.
Thks Hifivn,
Tried the 2 channel setting n it sounded muddy, Ran it last week with a sad Onkyo AV amp , The sound was much better.I guess ill have to go in for an Av amp for the DVD part,,,a bit of a bummer as i was hoping to keep it totally 2 channel. I really dont want to add a centre or a sub.