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Series Twin A7 Pensil (Gen.3 or A)

Howdy gents,

Preface: I have a DIY KT88 SET Kit in the works. Around 8 watts triode, 12 watts or so, ultra linear - it's still in shipping boxes waiting to be made..gulp.

Anyways, I'm kicking around the options of speakers to use with this amp - Options: A12Pensil, A10 pensil etc. etc. for (much) further down the highway.

Another option, I really like the idea of is 2 x A7 wired in series, in a floor-stander, both drivers firing forwards. I know 2 x A7 has been done before, in a monitor style, and another in a FAST, with one upwards firing driver.

I'm just putting this forward, for general discussion of the pros and cons of such a design. I'll start the thread discussion with...

1) Will this give me a more sensitive version of A7?[/B] +3 db for 89 - 90db or so?

2) Does a design/drawing for a new generation Twin A7 exist?

3) Are there simulated (gu)estimations of performance on a hard drive somewhere?

4) Could I use the existing drawing (from the FAST) and just move the upwards driver to the front?

Good idea or NOT such a good idea?

Comments?
 
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1) Will this give me a more sensitive version of A7?[/B] +3 db for 89 - 90db or so?

2) Does a design/drawing for a new generation Twin A7 exist?

3) Are there simulated (gu)estimations of performance on a hard drive somewhere?

1/ wired in series same sensitivity.
1a/ wired in parallel, ~6 dB more sensitivity.
1b/ no matter how you wire, 3dB more efficiency

2/ for a Pensil? Double the xsection of a single, and place the drivers such that the average Zd remains the same

3/ Performance will be the same as for a single driver, barring level shift and HF combing (likely a non-issue as long as drivers are as close as possible and listening distance is reasonable).

dave
 
1a/ wired in parallel, ~6 dB more sensitivity.
Might work, but a rather low impedance load on amp. resulting in possibly high distortion from amp, even if amp didn't overheat/blow up. So no free lunch?

1/ wired in series same sensitivity. 1b/ no matter how you wire, 3dB more efficiency

Sorry, I don't quite follow this Dave? Is there a db gain with series wiring? I thought it was +3 db?