Thanks for the feedback, guys - I realise that I need a better title for this thread - it should be '
OTC vs OTL' to be clearer to others what I'm trying to get at. Its about more than just trying to find a tube amp that works with low-impedance dynamic cans from A-T, Grado etc - its about trying to avoid the usual 'Buy every sub-$500 tube amp that comes down the pike till I find one that works !' methodology employed by some on Head-Fi. If transformers cost money BUT thats the reality of getting good sound from a tube amp, better to go in knowing that upfront,
non ?
I've started spreadsheeting various amps so I can see, at a glance, which designs are OTL. Companies like Decware and Woo make a point of assuring prospective customers that the transformers in their SET designs are proprietary - obviously, they know
we know how important the
iron is to the overall sound. Decware do sell an OTL SET headamp/preamp, the CSP2+, but I havent seen .it mentioned on Head-Fi in months, To be fair to Steve, he has enough on his hands with the Taboo and Mini-Torii back orders.
http://www.decware.com/newsite/CSP2.html
And an old standby in budget tube amps, the Little Dot MKIV SE, is an OTL
push-pull design. Seems to have plenty of fans here.
http://www.littledot.net/forum/viewtopic.php?f=9&t=820
Some may think I am placing too much emphasis on the presence, or
absence, of a transformer - they may be right, but my reasoning goes beyond an obsession with topology. If you live in a country which enjoys low Customs Duties and reasonable freight costs, the prospect of importing something like the WA22 may not seem too onerous. If you live in the US, you might have to pay some sort of State tax - Europe VAT etc, but in Thailand I will be faced with the prospect that
every $100 of the purchase price will attract $37.50 in Customs and VAT. Add freight charges on the heavier OTC design and you are rapidly faced with an all-up cost of up to 150% of the purchase price. Suddenly paying ~$3000 for a $2000 amp doesn't seem like a good deal - ymmv.
'What of local manufacture ?', I hear you cry - the irony is that these guys
specialise in building output transformers in Thailand:
http://www.sacthailand.com/
A single headphone amp and a pair of statement monoblock speaker amps - all expensive in USD equivalents - it soon becomes clear that the iron costs money regardless of where you buy from. Yes, there are other tube amp builders in Thailand, but they would be faced with the same parts costs (complete with SAC's profit margin on top...) and you wont find any English language reviews of their products. Google Translate ? No thanks.
My personal
Cheap Charlie ways aside, the bigger question is obvious - is there anyone outside of the likes of Atma-Sphere ($$$) with the smarts to make OTL work, be it headphones or speakers ? I'll keep working on that spreadsheet.
(apologies for the length of this post, but I suspect I'm the only one still reading this thread by now anyway ! Cool
)