holland
Headphoneus Supremus
- Joined
- Jun 15, 2007
- Posts
- 2,210
- Likes
- 22
follow up would be great, very curious myself.
Originally Posted by sceleratus /img/forum/go_quote.gif
"We will spec the amp before and after so you will have a record of what it is capable of."
I'll have a Blueprinted amp when it comes home.
Nervous......
I don't know that you failed. You have designed and built one of the nicest enclosures on this forum, period! Also note that you are diving into some what uncharted territory by converting an amp designed for speakers and modifying it for head phone use. Not an easy task, even for the most skilled builders. Indeed, I just finished reading through a rather long and interesting thread where a number of individuals are attempting to scratch design from scratch, something similar. I believe they spent about 30 pages just discussing the output transformer and even had a number of mfg's joining in the discussion. Not easy! Both you and the people on that other forum are aiming for the best that can be accomplished. I think you both will succeed.
Jim
PS. I admire your perseverance,
Thanks Jim.
Tom Christensen deserves the lions share of the credit.
The problem:
Something failed on the Maida regulator that produced the buzz/hum. I do not know specifically what it was. I did look through my build and saw that I used the wrong value for R-3. I used 10Ω. It should have been 15Ω
Post fix he sent me the following:
"We just dived into the amp and its much better and the hum is gone and draws 1/2 an amp less from the line.
The - 50-53db noise floor, is now -55-56 db with the choke and caps.
This is the limit for this circuit due to this -56db is the top of the switching noise, so can't go lower than that. Switching noise is a hiss, this can be heard now if you strain your ears."