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Ohms, my - help me understand

Apologies if following questions are dumb but some of this stuff is befuddling to me:

Just bought a pair of used Thiel CS2s, after auditioning with my Arcam Alpha 8 integrated. At home I had paired it with an Arcam Alpha 8 power amp to bi-amp B&W DM601 S2s.

Both amps are 50 watt amps at 8 ohms for two channels, 100 watts at 4 ohms single channel.

The Thiels, according to online reviews, are 6 ohm speakers that can handle 40 to 250 watts.

I had read Thiels were hard to drive so I was worred. But Larry at Hollywood Sounds said my amp would work fine and it did. They sounded terrific in his shop with just the integrated and even better at home, much richer and more detailed than the little B&Ws. It is true that expose bad recordings, particularly on CD, but the upside is spectacular). The Thiels have single binding posts so at home, I am now using the intergrated as a pre-amp, with the power amp running the speakers.

So here are the questions:

* How many watts are my amps producing with these Thiels. Is is as simple as splitting the difference between 8 and 4 ohm output, meaning 75 watts?
* The power amp can be turned into a monobloc, but the integrated can't so am I correct in presuming with single speaker posts that running one amp to each speaker is out?
* If I picked up a matching power amp, could I use the integrated as a pre-amp for both or would I need to buy a whole new preamp? The integrated has only on set of pre-amp input jacks.
* If I had matching Alpha 8 power amps to run each speaker, how many watts would be going to Thiels? 125?


As you can see, this is all about increasing power. I am thrilled with results in new set-up but from all I have read about Thiels, it makes me wonder what they would sound like with more juice. I don't have the budget to simply swap out whole system but wondering if a second power amp would be worth the bang for the buck.
maverick18
maverick18 OP
9 posts
 
Thanks for responses! The message seems to be I need more power.

Herman: Good idea. I'm probably not gaining much of anything with the power amp since I don't have biamping options with the Thiels.

I'll think about an amp upgrade down the road a bit because for the moment, I've worn out the wife's goodwill. The Musical Fidelty option sounds like a good one but rich for my current budget.

Unsound, thanks for advice. I've auditioned a lot of speakers, new and used from $400 to $2500, over the last couple of years and I agree these Thiels seemed like a terrific value for the money ($450 in 8/10 shape). Maybe it's just because they're new (to me at least) but they've been a tremendous upgrade from the small B&Ws. At the volume levels I use, which are modest, the Arcam seems to handle whatever they're demanding.

The bass is tight but evident enough, maybe because they're close to wall. I did find that a few old and cheap CDs sounded thin but so far only discovered a handful of those and records sing. I will definitely be keeping them for quite awhile.
unsound
7,329 posts
 
When the time comes, let us know what your budget is. Please understand that Thiels require quality first and extra power second. While Thiels will work with modest amps, they really benefit from a quality amplifier and a quality high powered amp even more so.
xiekitchen
821 posts
 
Unsound: you are probably right about Theil's impedance.. I could not remember theirs in particular but it sounds like they are one of the companies that try to provide fairly flat impendance curves.. yes from what I remember they require high quality amps with good current dumping and dampning factor... I remember hearing the bigger ones years ago and enjoyed them.
magfan
1,583 posts
 
I just looked up the 'road test' of the CS2 and indeed, the impedance is a fairly mellow line.
NO phase data provided, but the test remarks opin'd that they are indeed a fairly easy load.
Again, however, when dealing with speakers at this level, better amps produce better results power / listening levels considered.
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