Hi Guys,
I have read through some pages here and am leaning toward trying this AMP. I am not 100% Confident I can build it, but hopefully if I get stuck I can get some help.
I have some questions if someone wouldn't mind;
1) What are the dimensions of this and the weight please?
About 11.5" long x 7.5" w x 9" high (with tallish tubes). Weight is about 5 lbs.
2) What is the power supply? I am from NZ and we have 240v, do I need to specify at time of ordering?
You need to specify 240V at the time of ordering.
3) I am thinking of pairing this amp with the O2 Odac, will this be OK? What connection will run between the ODAC and BHCA?
That will be just fine. You will need a 3.5mm stereo to RCA stereo cable. Something like this:
http://www.monoprice.com/products/product.asp?c_id=102&cp_id=10218&cs_id=1021817&p_id=9767
4) I am fairly close to my budget, and I have read the speed-ball upgrade is worthwhile, I'll be pairing this with my HD650's
I don't think the speedball is a required upgrade. I'd wait - you can always add it in later.
5) I already have an Asus Xonar STX, which is apparently a capable Dac/AMP, is it reasonable to assume the BHCA will be a reasonably noticeable upgrade? I have just been conversing with someone who has the STX and the Dot III and they said listening they thought the Dot III was better, but in a blind test they couldn't pick them apart from the STX. I am concerned about spending $400 and not getting a noticeable improvement.
An OTL Tube amp like the Crack does sound different to me (and I can pick it out against solid states in a blind test). Improvement may not be the right word - I like the sound. But I don't know if I could say it is better or worse, it is different. YMMV.
6) Which parts are most likely to get damaged in assembly, and should I order spares? I guess I am mostly concerned about parts getting too hot during soldering, and secondly damage caused by mis-assembly and having to wait weeks for replacements.
It's a pretty simple build, I don't think you have too much to worry about. I expect the most fragile pieces would be the Diodes (LEDs in the input tube assembly, and those in the power supply).