AudioCircle
Other Stuff => Archived Manufacturer Circles => Aspen Amplifiers => Topic started by: poseidonsvoice on 26 Sep 2010, 04:52 am
-
Would a Jensen transformer (http://www.jensen-transformers.com/datashts/11bmcf.pdf) or Lundahl input transformer (http://www.lundahl.se/pdfs/datash/1676.pdf) or a Ballsie Lite (http://www.twistedpearaudio.com/linestages/ballsie.aspx) do?
Of course the transformers have the advantage of galvanic isolation but they are also more expensive options.
Thanks.
Anand.
-
Yes, absolutely, Anand.
My preference is for the Jensen in the US, Lundahl in Europe.
Why, in light of the considerable cost difference with the Ballsie Lite?
#1 A transformer offers galvanic isolation, which kills earth loops in their tracks. Earth loops can be almost impossible to eliminate with some gear if galvanic isolation is not adopted.
#2 A transformer will deliver natural low and HF rolloff without the phase shifting complication of filters.
#3 A transformer has primarily H2, H3 and H4 harmonic artefacts which are musically benign, in contrast to a high negative feedback IC which has odds predominating over even up to about 25 orders.
#4 The recording and music performance industries use almost nothing else but transformers, they are that reliable, effective, and durable.
So there you have it.... and the NAKSA 70 does not have a topology which easily lends itself to electrical conversion to balanced line, so go for it!
Cheers,
Hugh
-
Yes, absolutely, Anand.
My preference is for the Jensen in the US, Lundahl in Europe.
Why, in light of the considerable cost difference with the Ballsie Lite?
#1 A transformer offers galvanic isolation, which kills earth loops in their tracks. Earth loops can be almost impossible to eliminate with some gear if galvanic isolation is not adopted.
#2 A transformer will deliver natural low and HF rolloff without the phase shifting complication of filters.
#3 A transformer has primarily H2, H3 and H4 harmonic artefacts which are musically benign, in contrast to a high negative feedback IC which has odds predominating over even up to about 25 orders.
#4 The recording and music performance industries use almost nothing else but transformers, they are that reliable, effective, and durable.
So there you have it.... and the NAKSA 70 does not have a topology which easily lends itself to electrical conversion to balanced line, so go for it!
Cheers,
Hugh
Thanks for the informative response Hugh! You don't have to convince me, I already use it in one of my other solid state amps, a gainclone. I just wanted to make sure that the application was just as straightforward with your amp designs too. Incidentally, one of the largest Lundahl distributors is right here in the U.S. (K&K Audio (http://www.kandkaudio.com)), and imho, the Lundahl 1676 is sonically superior to the Jensen 11-bmcf, albeit at slightly higher cost.
Anand.