hypex ncore

[pos]

Acording to the LS1 white paper:

The power amplifiers are UcD180 modules, slightly
modified. Their frequency-independent distortion and
extremely low output impedance minimizes their sonic
footprint, a trait that has earned these amplifiers a following
in mastering studios.

[ChrisPa]

Originally Posted by Sam Lord

Chris, were those photos of the corrected layout? Wires ought to be twisted *tight*. You can drop a length in half easily with enough twist. But why not just trim the wires?

Others (Julf?) have said that you can place various parts very closely without measurable effect. But I would really want to keep the PS in front and the ncore in back, keeping the input and output leads ultra-short. The AC line could be shielded on its way to the PS. Just random thoughts.

Your cases look good and are aluminum. If anyone uses steel cases they should keep the wires and all parts away from the steel. Better yet, don't get steel.

I know, I should just buy and build some ncores and shut up.

No, they're photos of the original layout. Effectively the bit of speaker cable you can see is the side of the single-turn helix. They are twisted as tightly as the stupidly thick bit of speaker cable off-cut I used would allow. I haven't taken photos of the rearranged cable routing.

As I said in my original post, the underlying reason was convenience and ease of assembly. These cases were intended to be a comparatively temporary neater/safer alternative to a piece of chipboard. And as the cases are a bit of a 3D jigsaw, it was a comnination of leaving the Hypex harnesses untouched and ease of assembly (of the speaker cables) while the cases were apart. Unfortunately the sound quality ended up lower than a piece of chipboard (maybe it's because there's not enough wood in the case................ )

[OllBoll]

Originally Posted by Bruno Putzeys

Well yes, sorry for the bad news. I know the advantages of current drive quite well (use it on the LS1) but the problem is that such a product would nevertheless be for a minority of savvy speaker designers. I think at this point the DIY spirit will have to kick in - I mean that some people might build a current feedback loop to wrap around a UcD/Ncore amp instead of waiting for the same guy to solve all problems

But it's so nice when it has been done by someone who really knows what he/she's doing

I would find it awesome if someone published a DIY guide on how to do that, so that even I who don't know circuit design but likes to build stuff can have a go at it

[troystg]

Originally Posted by OllBoll

...But it's so nice when it has been done by someone who really knows what he/she's doing ...

+1 for the "who really knows what he/she's doing "

[bclare]

Originally Posted by pos

Acording to the LS1 white paper:

The statement of low output impedance would imply voltage driving, not current driving.

[pos]

Indeed, that is why I quoted it. It might have changed in the prototype Bruno is currently using though.
I think current drive is a really important matter, as it address some sort of distortion in the driver itself. It is an incredible and somewhat overlooked tool for the DIY speaker builders that many of us here are.

[Julf]

Originally Posted by pos

I think current drive is a really important matter, as it address some sort of distortion in the driver itself. It is an incredible and somewhat overlooked tool for the DIY speaker builders that many of us here are.

While it isn't a magic silver bullet, it is definitely a valuable technique if you are designing your speakers from scratch. Doesn't really help those of us who are working with existing designs.

[pos]

Nelson Pass has a paper of his website about the benefit of current driver (mainly regarding frequency response...) with fullrange drivers.
When multi amplifying drivers that operate in narrow ranges (above their resonance frequency and under their impedance rise) current drive amplifier can be used without any modification.
I think if this technique was more common we would see more drivers and even complete speakers designed for current drive amplifier. But this has to start somewhere, and these forums are the ideal place for that as it has both amplifiers and loudspeakers DIY sections!

[waltzingbear]

Originally Posted by bclare

The statement of low output impedance would imply voltage driving, not current driving.

having a hi-z amp is not the only way to implement current drive in a system.

Alan Garren

[yetis]

Originally Posted by earflappin

Yetis, I would refer you to look at Figure 2 on page 12 of the NC400 data sheet. The preferred connection is for NAMPON (and XLR pin 1) to be tied to chassis ground. On my NC400's I wired NAMPON directly to XLR pin 1 as I don't have mine in chassis yet and they worked flawlessly. Good luck.

So I got one of them to work and well I might add. Now I am really flustered. This as I have one that works and one that does not. They are wired identically. I have a circuit tester and all the grounds, xlr connections, etc all seem to work the same, yet one works and one doesn't. There was never any "issues" when I was working the units. They both just simply click, when I plug them in -- with one working. The thought of breaking them both down and swapping the amps to isolate the issue, isn't high on my list. Any suggestions?

thanks
Thanks