1) I just got a 42 inch TV, which comes with speakers wires that comes out of the TV and then it input into the TV speakers. But the sound is very crappy. So I re-direct the speaker wire into my old Mercury M2 speakers. Sounds great - but soft as the M2 is a 8 ohm speaker, and I think the TV built-in amp cannot power it well. Someone suggested that I look at a 6ohm speaker like Wharefadale Diamond 9.1
2) Assume I do that, and if I want to extend the idea have a nice 5.1 system, which is a good cheap package that utilizes the Diamond 9.1 for normal TV watching, and if I am playing DVD with 5.1 sound, then with the 5.1 system, I can switch over. Meaning that, while watching normal TV, it is stereo - I do not need to turn on the Amp or processor or 5.1 system. Just pure speaker in cable powered by TV built-in amp. Then if I am watch solid DVD, I turn it on and solid 5.1 sound is produced.
Any suggestion for this wierd requirements?
Music wise - I listen mainly to POP music and occasional piano and classicle music. My old Hi-Fi is pure stereo but I am seriously looking into 5.1 now - but I have a budget problem. I hope not to spend more than 800-900 USD for total setup.
If the sound from your M2's are significantly less powerful than from the TV's on board speakers you may have an impedance issue but I suspect that the TV 10 watt amplifier is the real issue. I would urge you to begin the process of shopping for your 5.1 system that you will be able to use for both TV viewing and for DVD's.
Yes, the TV amp is weak. So it cannot drive the M2. Most of the time (90%), it is used for normal TV watching, cartoons by kids etc. So I do not want to turn on the 5.1. Just use M2 or 9.1 or the default speakers that comes with the TV for normal TV watching.
And 5.1 for nice DVD with those dolby/thx encoded sound.
So I hope to shop for a reasoably price 5.1, that uses low impedence speakers like 6ohm type.
The next question is if you have a retailer nearby that you could go visit to listen to different systems especially a store that sells Wharfedales. I would also check the owners manual of your TV to see if it mentions anything about running external speakers for fear that the potential impedance mismatch might causer damage to the TV's audio section.