Amp10 Questions for B&O Penta Speakers

[snoopy]

I'm buying some B&O Penta speakers which are the unpowered version and I have a couple questions regarding the Amp10. I already have an Amp6 with a SMPS and love it to bits but the power isn't nearly enough.

The speakers are 150w @ 8ohm

I would like to get close to this without distortion so my intention is to bridge the Amp 10 and go for the full 200W capacity but use sufficient line-in resistor to ensure I never go over 150w with my "trusted" input sources. Can you tell me:

1. what VA toroidal I would require and at what +- voltage. It will be powering 2xAmp 10 in switched config with a max of 150W into the 8ohm so 300w maximum.

2. will the four capacitors and extra rectifier on the non-basic help with the power or can I expect it to work ok?

3. what does the relay do on the basic?

4. Has anyone used a SMPS on the Amp10? Is it more efficient than a toroidal transformer? and if recommended is there any that can supply the high wattage I'm after at the optimal voltage?

5. which sounds better, the basic or non-basic?

Many thanks

Andrew

[Boolzor]

"what VA toroidal I would require and at what +- voltage"

=> I m looking for this information as well for my Amp10-Basic; there is thousands of toroidal and I'm not able to choose a right one with short informations provided

[thomaseliot]

Boolzor,

a basic trasformer is this:
http://www.selectronic.fr/article.as...r=80.5504-9999
or better this
http://www.selectronic.fr/article.as...r=80.5513-9999
and if you can afford this:
http://www.selectronic.fr/article.as...r=80.3223-9999

With 21Vac you get 29-30VDC and 50W max power (and max distortion). It will have acceptable performance at 30W 8ohm.

Snoopy,

TA2022 is 150W 0.1% THD when bridged. 200W is theorethical power at max distortion, and I don't think the amp can source enough current for that power. So you need no external circuits.

Max DC voltage for bridged operation is 30V, so you need a big toroidal transformer at least 500VA with two secondaries 21 or 22 VAC.
You can use the links above: same voltage but as big as you can.

(If you don't live in Europe it is not a good idea to buy there)

[Boolzor]

thanks a lot !!

[soundexcel]

If you want to bridge the amp for a 8 ohm load.
The amp needs a 18V transformer. This is for a 4 ohm load on both channels.

A 220VA transformer would be sufficient.

[snoopy]

Thanks for that, I've decided not to go with Penta's and stick with one AMP10 Basic. 400VA transformer on order. Final question, I want to replace the input caps with my own which are 2.2uF. Will any resistors on the input side require changing as I know the default cap is 3.3uF?