Thanks all for the comments; let me add a few more bits.
I decided to attach the front and rear panel with mushroom head Allen studs, and took the plunge with tapping all attachment holes. I bought all the right drills and taps, then drilled and countersunk the holes in the heatsink ends. I blunted the elongated tip of the tap on my grinder, placed a piece of old pcb between the heatsink fins as a stop, dipped the tap into methylated spirits, then used my DeWalt 9.6V trade grade cordless to tap all holes. This technique works wonderfully with aluminium, and prevents filings clogging the tap. Result was perfection all round, all done inexpensively, professional job. I was !@#$ delighted.
Sean has it 100% right. Two LEDs, Sam, one for each power supply. The new pcb for the N+ is 13mm longer (half an inch) and 8mm wider (5/16"). The front panel is a tad plain, I agree, and Sean and I discussed this at length last night. I must approach Julian at Conrad Engineering for costing to see how practical a solid Al front panel with AKSA cast into it then milled flat would be...... Alternatively, we could use CNC milling of a simple 5mm panel, but I suspect the casting would be cheaper per unit.
Carl is dead right about shipping costs, but this is just a fact of life. A cheap rate with FedEx from Conrad Engineering who move about 2 tons of heatsinks overseas each month was $AUD235, which is around $US170. This was just under double my initial estimate. Fitting the amp with transformers would have added appreciably more weight (another 4.8Kgs, or 10.5 lbs), and would have cost more. It's a bind, but OTOH it was delivered without incident in just three days. You can't have it all, where would you put it??
The case was designed almost obsessively as an engineering solution rather than as eye candy for a retail product, and there is no doubt that with an improved front panel it would be a much more elegant solution. Branding is the name of the game, and while I will use a different brand for the plug and play GK1 Swift, I will also need to have a proper DIY Aspen logo. I might soon have some logos made, and with a suitable amendment on price I will eventually include them in my range of kits.
The AKSA power amplifiers are finally becoming very mature products, and hold their own with almost anything in the market. I was reading a Stereophile review of the WAVAC 833 SET amp, designed after Nobu Shishido, which reputedly performs brilliantly and is a steal at $USD350K. I am genuinely humbled by the brazen pricing policy, and it reminds me bluntly that the common perception of most consumer products is based entirely on price. AKSAs are easy to build, and very refined, although the break-in period for the N+ is a bind I don't seem able to improve upon. (I suspect even a WAVAC has a break in period, however!) One customer (you know who you are, many thanks Pierre!) tried 'burning in' the caps on a special jig we discussed. It made almost no difference; he still had to wait more than 100 hours for it all to come together. However, if you resign yourself to this, like training a good racehorse, and just set the source softly playing on 'repeat' while you are out during the day, it will soon come round. I still think the Black Gates sound better than any other cap, and the NX couplers are superior to just about all the film caps I've used.
A lot of talk recently about Chris Venhaus' new teflon V-caps. I have tried the TFT from RelCap at $US22.50 apiece almost two years back!! In the charge suckout position on the AKSA the result was mixed. Sensational midrange and top end, absolutely no bass. I was staggered. I have never seen or heard anything like it. But for an active system, specifically the top end amp, I had the impression the AKSA ranked with the best single ended tube amplifiers, and yet boasted an order of magnitude more power....
Chris, I have to say Carl has done an excellent job! Carl, my congratulations, you can be proud!
Cheers,
Hugh
[Edit Advice: Apologies to Vladimir Lamm, the amp in question was the WAVAC, for I have duly changed the attribution. HD]
