Nuuk said:
Perhaps I misread the article that dates from 2003 to 2006. Oops.
For me this project is because I've never had a LM3875 come out right. . . but I'd like to have one that's right.
EDIT: This might all sound really nuts, but just consider it a meticulous attention to detail.
Howabout just a guess on average cable length?
EDIT: I'd much rather have your guess than mine.
And yet you speak with such authority when you advise other people how to build a chip amp!
Did you not understand what MJL21193 meant when he said
It's good to pay attention to detail, but not at the cost of losing sight of the goal.
That would be the length of the longest cable that I used, plus the length of the shortest one, with that total divided by two. 😉
Nuuk said:
Thanks man!!! 😀 😀 😀 😀 😀 😀 😀 😀 😀 😀 😀 😀 😀 😀
This is much more convenient and easier than I thought it was going to be.
Dan, as it is January 3rd, and the festival of St Gain Clonius, and as I have just enjoyed a very nice supper, let me tell you that the length of the umbilical cable that I am currently using is one metre.
This was chosen specifically because the cable was sold by the metre! 😉 And there is no other motive or reason for using that length. The cable in question is four-core 1.5mm mains lead with a black jacket.
But I am puzzled that you have not had success with the LM3875. Are you able to tell us what speakers are you using?
This was chosen specifically because the cable was sold by the metre! 😉 And there is no other motive or reason for using that length. The cable in question is four-core 1.5mm mains lead with a black jacket.
But I am puzzled that you have not had success with the LM3875. Are you able to tell us what speakers are you using?
Nuuk said:
It was the mention of the aluminum boxes purchased for the PSU enclosures, that had me thinking the power supplies were external.
Sorry about all the cable questions.
My previous experiences with LM3875 were much different than with LM1875.
I found LM3875 to have peakish upper-mids (shout) with just about every option attempted.
I also have a T-amp, an old 1962 pioneer tube amp, LM1875, TDA7294, TDA2050, TDA2003BTL, several NEC's, and an STK 459. These don't do peakish upper-mids (they don't shout). My class-D pa amp didn't shout, but it expired from hard use. The old PA amp (now put back into service--freakishly heavy thing, but reliable) has an inbuilt triband baxandall with a bunch of switchable options, so there's no telling if it shouts or not.
My parallel LM3886 doesn't shout, but the single's were almost as painful as my non-inverting LM3875's.
As for speakers, I have a little full range, a 2-way, an ohm walsh copy, a generic sealed box 8" retail 3-way (useful for testing amplifier's control of woofer), several large PA speakers (in the workshop, awaiting "wideband" retrofits), and I have a b20 with series crossover. There's a bunch of Tang Band's ws6's, not yet built up. I also have several varieties of headphones, that are perhaps more useful than speakers for making observations.
One puzzling note on the B20's is that, maybe, they should be playing more level with LM3875's and LM3886's. That wasn't the case, according to the emails I got from the B20 builders group (whether it was mine or audiosector). This, I didn't understand.
So, you see, my experience with LM3875's was quite the opposite of the description in your article. This is why I want to hear yours. 😉
And, thank you for the opportunity.
- Status
- Not open for further replies.