i think hypex usually uses ups, so it should be normal, mainly because hypex also declares full customs value, a lot of sellers would claim lower customs value to help out customers, but i don't think hypex wants to touch that.
the value of the goods should not have an effect on the fee UPS charges... only tax and duties depend on the value afaik
sorry if was not being clear, i was talking about declared customs value in that it does affect tax and duties
ups fees do not change unless there is insurance purchased.
Legato 3 and nC 400
Who knows why the ~9V of common mode DC at the output of the Twisted Pear Audio Legato 3 does not play nice with the nC 400 modules? The signal in the nC 400 input stages is actually ground referenced in a way?
Seems like two possible solutions: add coupling caps, or transformer couple the amps' input… Opinions?
Who knows why the ~9V of common mode DC at the output of the Twisted Pear Audio Legato 3 does not play nice with the nC 400 modules? The signal in the nC 400 input stages is actually ground referenced in a way?
Seems like two possible solutions: add coupling caps, or transformer couple the amps' input… Opinions?
Because the nc400 is DC coupled, and amplifies the DC as well as any signal.
If a device puts a significant DC voltage at the output I would consider it a design error (or artificially improving your measurement results by leaving out the series capacitor that should have been there).
No, not really, the common mode rejection ratio is pretty high.
With that much DC, you will offset bias a transformer pretty badly, so a coupling cap is the way to go.
Julf...
Thanks for the response. I think you may misunderstand though.
The Legato 3 has around 9 VDC from + to G, and from - to ground. That is, the differential output is centered 9 V away from G. This is not technically DC offset of the differential signal. The signal from +/- can be easily trimmed to a stable offset of an insignificant 0.1 mV or so. Many people have success using this output stage with true differential input amplifiers where the signal is not ground referenced even with an amplifier which is DC coupled. There is nothing wrong with the design of the Legato 3, these qualities are well known, it is a design choice. We are only considering the balanced output here, for the single ended output (which sums the differential stage via an IC opamp) all DC is eliminated.
With a transformer, one can connect only the differential output of the Legato 3 (plus and minus output), and take the ground on the transformer's output from the centertap of the transformer-there is no need to connect the input side of the transformer to the ground of the Legato 3, so there will be no DC to bother the transformer.
I am curious as to the nature of the nCore input stage now. Apparently the input stage is ground referenced via the shield connection of the input connector?
Thanks for the response. I think you may misunderstand though.
The Legato 3 has around 9 VDC from + to G, and from - to ground. That is, the differential output is centered 9 V away from G. This is not technically DC offset of the differential signal. The signal from +/- can be easily trimmed to a stable offset of an insignificant 0.1 mV or so. Many people have success using this output stage with true differential input amplifiers where the signal is not ground referenced even with an amplifier which is DC coupled. There is nothing wrong with the design of the Legato 3, these qualities are well known, it is a design choice. We are only considering the balanced output here, for the single ended output (which sums the differential stage via an IC opamp) all DC is eliminated.
With a transformer, one can connect only the differential output of the Legato 3 (plus and minus output), and take the ground on the transformer's output from the centertap of the transformer-there is no need to connect the input side of the transformer to the ground of the Legato 3, so there will be no DC to bother the transformer.
I am curious as to the nature of the nCore input stage now. Apparently the input stage is ground referenced via the shield connection of the input connector?
OK - thanks for setting me right. Yes, in that case a transformer is OK.
Common mode rejection ratio is 55 dB.
Hello, i'm new on this forum. But after reading a lot about the hypex NC400 i'm interested of listening to a pair of those amps. Is someone willing to bring me a visit with a set of NC400 amps? I want to hear them on a set of ATC SCM 20's
I live in Meppel, the Netherlands, maybe someone near Meppel with a set of these amps?
Regards Frans
I live in Meppel, the Netherlands, maybe someone near Meppel with a set of these amps?
Regards Frans
Is it 48 V single-ended, or +-48 V?
It is on the lower side, but should at least allow you to do some testing.
+-48 yes.
I will think about it, because on another hand, I don't want to be disapointed with the listening... if the PS is limiting it too much.
Thanks for the feedback anyway.
I have SCM20SL also, great speakers. But in evaluations I often crank them up to full power@6 Ohms using my Bel Canto S300 amps, which clip at about 200W (biamped: 200 W into tweeter and 200 W into midbass) into the ATC's 6 Ohm impedance. So if you listen loudly as I do (not that loud, the ATCs are quite inefficient), you should be sure to supply all the clean power that the nCores will need. I still plan to get some nCores for my speakers, FWIW. Cheers
Having owned both BC S300 and Ncore amps - the Ncores totally wipe the floor. The S300 can sound a little thin and dry by comparison. Either Ncores as an upgrade you will be happy with - or look for an S500ref Bel Canto which will give a fuller richer sound (I've owned s300 S500REF and REF1000 monos - now have the Ncores.
nope, i made a few changes along the way, including binding posts and iec inlet, that and i changed from the mogami to the newer hypex supplied xlr wiring. so who knows what it was. i'm just happy with the way things turned out, nothing scientific here though.
got my ncores rebuilt into a different chassis, and i swear i hear a difference, don't know if its the isolation of the ncore/smps modules or something
Thats the nicest build I have seen!
The only thing I would have done differently is to route the speakerwires a little bit away/around the big inductor. I have seen companies using nc1200 doing that.
Why twisted
Nice build!
Is there a special reason that you twisted the connections between the PS and the NCores?
I saw a picture of the Mola-Mola (Bruno's "own" brand with the NCores) and there only the mains and the LS connections were twisted.
Somebody any ideas what is best?
regards
Joost
Nice build!
Is there a special reason that you twisted the connections between the PS and the NCores?
I saw a picture of the Mola-Mola (Bruno's "own" brand with the NCores) and there only the mains and the LS connections were twisted.
Somebody any ideas what is best?
regards
Joost
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