Molex KK series pin
Hi Jan-Peter,
I did an audiophile experiment on my 4-channel ucd180. I connected the speaker wires directly onto the flat pin connectors on the ucd180 pcb. The difference was huge. The soundstage got bigger and more solid, with greath depth. The highs got cleaner, bass tighter. Overall a remarkable improvement in musicality. Now I want to connect the signal cables directly onto the ucd180 pcb as well. But the Molex signal connectors are small and fragile. You have any suggestions on how to proceed? It would be ideal to have the same type of big flat pin connectors as the speaker and power terminals.
PS: The hypex amps are stunning on my Wadia 861/active 2way WLM speaker system.
/Thomas B
Jan-Peter said:
Hi Jan-Peter,
I did an audiophile experiment on my 4-channel ucd180. I connected the speaker wires directly onto the flat pin connectors on the ucd180 pcb. The difference was huge. The soundstage got bigger and more solid, with greath depth. The highs got cleaner, bass tighter. Overall a remarkable improvement in musicality. Now I want to connect the signal cables directly onto the ucd180 pcb as well. But the Molex signal connectors are small and fragile. You have any suggestions on how to proceed? It would be ideal to have the same type of big flat pin connectors as the speaker and power terminals.
PS: The hypex amps are stunning on my Wadia 861/active 2way WLM speaker system.
/Thomas B
Have you tried putting the connectors back on as original? Maybe you just removed surface oxidisation by unplugging or mains was better quality during your tests? I've often been caught out by something I thought made a large change and it's just the human brain being in a better frame of mind during the 'good' times 
richie00boy,
Yes - that was my first thought. This can't be true. I swapped between original and directly coupled connections. Still the soundstage was bigger and more rock steady on the latter. I really couldn't believe my ears that the soundstage was soo deep.
/Thomas B
Yes - that was my first thought. This can't be true. I swapped between original and directly coupled connections. Still the soundstage was bigger and more rock steady on the latter. I really couldn't believe my ears that the soundstage was soo deep.
/Thomas B
Thomas B said:
What do you mean by "directly coupled connections"? Did you solder the wires that go to the speaker directly to the connectors?
If so, yes, I did that too. I also soldered the input cables directly to the pins of the molex connectors.
However, for my UcD400s I was planning to use connectors.
Best regards
Gertjan
Gertjan,
To be specific, I crimped the speaker wires to flat pin connectors which I in turn attached to the flat pins on the ucd180 pcb. This way the flat pins on the pcb remain intact and I can still experiment with other speaker wires. Ideally I should want the molex KK series input pins on the pcb to be like the more sturdier flat pin connectors. Perhaps I can unsolder the molex KK series connector and replace it with flat pins. In further hypex versions it would be nice if this option exists.
Regards/Thomas B
To be specific, I crimped the speaker wires to flat pin connectors which I in turn attached to the flat pins on the ucd180 pcb. This way the flat pins on the pcb remain intact and I can still experiment with other speaker wires. Ideally I should want the molex KK series input pins on the pcb to be like the more sturdier flat pin connectors. Perhaps I can unsolder the molex KK series connector and replace it with flat pins. In further hypex versions it would be nice if this option exists.
Regards/Thomas B
Attachments
Thomas B said:
How else would you have attached speaker wires to the UCD180 board? I must be missing something here?
ewildgoose,
Normally you attach the speaker wire to the speaker connector at the rear panel of the amplifier enclosure. From the speaker connector then another wire is attached to the ucd180 pcb. That's a lot of connections. I skipped the connectors altogether and connected speaker wire directly onto the ucd180 pcb flat pins, thus getting much better sound quality and wider and deeper soundstaging.
Regards/Thomas B
Normally you attach the speaker wire to the speaker connector at the rear panel of the amplifier enclosure. From the speaker connector then another wire is attached to the ucd180 pcb. That's a lot of connections. I skipped the connectors altogether and connected speaker wire directly onto the ucd180 pcb flat pins, thus getting much better sound quality and wider and deeper soundstaging.
Regards/Thomas B
Thomas B said:
OK, that explains it.
I'm playing with the thougth of building the modules somewhere in my active speakers, so all high power connections can be made very short. On the other hand, I don't want the modules to be subject to too much vibrations, so still not decided (as always).
Gertjan
Gertjan,
I have had exactly the same idea. A minor problem in my case is that I can't split the active outboard crossover in two. Both high/mid channels are housed in a single aluminium box. It would be nice to have everything inside the speakers, so this is also not decided yet. I think it would be an improvement though to minimize speaker cabling.
Anyone having any experiences with fitting hypex modules inside speakers?
I have had exactly the same idea. A minor problem in my case is that I can't split the active outboard crossover in two. Both high/mid channels are housed in a single aluminium box. It would be nice to have everything inside the speakers, so this is also not decided yet. I think it would be an improvement though to minimize speaker cabling.
Anyone having any experiences with fitting hypex modules inside speakers?
Putting UcD's in the speaker boxes and having a separate box for the active crossover allows you the opportunity to use a nice balanced interconnect to the speaker, thereby keeping noise very low as unbalanced source-crossover interconnect can be kept short 😎 Also wave bye bye to ground loops.
<<Now I want to connect the signal cables directly onto the ucd180 pcb as well. But the Molex signal connectors are small and fragile. You have any suggestions on how to proceed? It would be ideal to have the same type of big flat pin connectors as the speaker and power terminals.
PS: The hypex amps are stunning on my Wadia 861/active 2way WLM speaker system.
/Thomas B >>
What I did is solder thin OCC copper wire from the XLR connector to the signal input at PCB. I was tempted to make OCC copper balanced interconnects to be soldered directly to the signal input but was affraid of lack of shielding.
It sounds great to me 😉
Good luck
Mauricio
PS: The hypex amps are stunning on my Wadia 861/active 2way WLM speaker system.
/Thomas B >>
What I did is solder thin OCC copper wire from the XLR connector to the signal input at PCB. I was tempted to make OCC copper balanced interconnects to be soldered directly to the signal input but was affraid of lack of shielding.
It sounds great to me 😉
Good luck
Mauricio
Yves Smolders said:
So what do we use? I found this, but it also has common ground.
http://www.ampslab.com/dcpro.htm
I have just tested UCD180 with my Linkwitz Orions midwoofer. When comparing sound to Rotel RB971, i can not notice any big difference. Maybe it is beter to put UCD in cabinet before make any conclusions. For now i have only crappy test connection made above MDF.
I use dual mono with Mur820 double rectifiers/channel, bypassed with polypropylene caps. Filter capacitors are Rifa PEH200 10000uF/63V bypassed with 33uF Aydyn Cap polypropyne + 0,1uF. I know that Bruno has said that bypass caps are not needed but can these be even bad, because there are also bypass caps in module itself?
How about change small electrolytics to eg. polypropylenes in module.
Can it improve sound quality?
(I remember that somebody has said that change 470uF caps is not worth of)
Is it possible to use smaller caps in module when using UCD in midwoofer (120-1,5khz) or tweeter (over 1,5khz)?
I use dual mono with Mur820 double rectifiers/channel, bypassed with polypropylene caps. Filter capacitors are Rifa PEH200 10000uF/63V bypassed with 33uF Aydyn Cap polypropyne + 0,1uF. I know that Bruno has said that bypass caps are not needed but can these be even bad, because there are also bypass caps in module itself?
How about change small electrolytics to eg. polypropylenes in module.
Can it improve sound quality?
(I remember that somebody has said that change 470uF caps is not worth of)
Is it possible to use smaller caps in module when using UCD in midwoofer (120-1,5khz) or tweeter (over 1,5khz)?
Attachments
ghemink said:
I messed it up a bit,
This is what I wrote:
Does your UcD180 have caps at the input? The UcD 180 that I have (old ones) have 22uF caps in the signal path between input opamp and the UcD amp part itself. I replaced those caps with smaller BG caps for the amps that feed the midwoofers and tweeters. I would not reduce the size of the power supply decoupling caps. And replacing them with "better" caps may actually make things worse. Bruno has replied something like that a while ago. If you use very low series resistance caps, you can get high frequency ringing in combination with small ceramic caps in parallel.
Actually that happens, I did not confirm it on the UcD but I took a BG 100uF cap (if I remember correctly, for sure it was a BG), I put it in an RC network and feed that network with 10V amplitude square waves. If the cap is ideal, you should get a triangle wave over the cao. Of course it has a small jump when the square wave changes polarity, this is due to the Rs. When I put a 100n Rifa cap in parallel, I got a "nice" 4Mhz or so ringing at the moment the square wave switches polarity. With "bad" caps (read higher Rs) you don`t see that because the oscillation is damped with the series resistance of that cap. So be carefull, better is not always better.
Gertjan
ghemink said:
Thanks for information.
My modules are revision2, i have not checked connections of caps.
If i understand correctly, only input coupling caps (if exist) are worth of change in module.
I read in some post back Bruno or Peter strongly discourage bypass of the electrolitics. I experienced this already in the past with other amps. Bypass caps strongly affect transient attacks especially in the bass region.
Giorgio
Giorgio
Pasi P said:
i've noticed that decoupling the psu with film caps degrades the sound , but snubbers ( for example 1R+100nF) improve it
alain