VTV Hypex Ncore NC252MP (It's all Amir's fault)

[sejarzo]

And how does that audible problem manifest? What I see is the least expensive Hypex amp on the market. The problem is widespread and can be fixed by moving 2 wires, and it's shipped from the US. Perhaps you are about to become uncompetitive.

Not necessarily. Because the pricing info on the Audiophonics site includes VAT that is not charged to US buyers, and there's no clear explanation about how much one would cost if delivered to a US address, I asked them about that last week, and the reply was:

That total of 436€ at today's exchange rate is US$473 for their NC252MP unit.

 

[sejarzo]

Just be clear, nothing taken out of context and I didn’t bring up the other thread the other gentleman did. The quote was posted in its entirety, if that’s not what you meant no problem like I said I didn’t really mention it at all nor do I really care much, other than posted it for accuracy.

BS. You didn't bother to carefully read the referenced thread to grasp the context of the reply. March Audio never stated that the XLR ground not being connected could be dangerous but was referring to earth grounding of the mains and the pin 1 problem as separate issues in the reply that you posted.

 

[sejarzo]

I actually asked that question has anyone actually had any problems due to grounding etc. not just with this amp, but any other other products that they own? It will be interesting to hear some real life problems if any not just speculation. Personally I have not had any issues, we are talking about high-level signals. Low-level stuff, microphones, tone arms etc. totally different.

Yes, I have had numerous issues with my powered subwoofer, either with its original Class AB amp or the replacement Class D plate amp that was supplied when the original developed a mechanical hum under warranty. I had to use an isolation transformer in line between my active crossover and the sub on the unbalanced signal cable to get rid of mains induced hum with the Class AB amp. I was pissed when I installed the Class D replacement, because immediately, there was hum with the isolation transformer in line when I reconnected it....that went away immediately when I removed the transformer! I then put the transformer back in and the hum came back. Yeah, weird, but it happened.

 

[rebbiputzmaker]

BS. You didn't bother to carefully read the referenced thread to grasp the context of the reply. March Audio never stated that the XLR ground not being connected could be dangerous but was referring to earth grounding of the mains and the pin 1 problem as separate issues in the reply that you posted.

View attachment 62915

Cool thank you very much. But there was not actually an earth grounding issue in the amplifier being discussed. Can a hypothetical earth grounding problem be dangerous? Of course, and useful to point out in general discussion, just unrelated to the amp in question.

 

[March Audio]

I am guessing, but computers tend to emit a lot of RF and have a lot of electrical noise. I could also see the issue being worse for those using a dac built into their PC. In my case, I use an outboard USB Dac so don’t have that potential issue.

Its actually often an issue created with switch mode supplies. They have leakage currents which get on to the ground. Computers can still dump noise currents on the ground regardless. Im afraid you dont escape the potential problems by having an outboard dac.

 

[sejarzo]

Its actually often an issue created with switch mode supplies. They have leakage currents which get on to the ground. Im afraid you dont escape the potential problems by having an outboard dac.

Yep. I have a Fiio K1, a Tempotec Sonata HD, and a Topping D10, all USB powered, that have different levels of "computer noises" on their analog outputs if connected to the same port on the same PC or laptop.

 

[VTV Amplifier]

Thank you for the exposure on the NC252MP...... all amps shipping now wire the XLR pin #1 and XLR case to chassis ground, a small difference.

 

[CDMC]

Thank you for the exposure on the NC252MP...... all amps shipping now wire the XLR pin #1 and XLR case to chassis ground, a small difference.

First welcome to the forum. Second, I am happy with my VTV and consider it a great purchase.

 

[Xulonn]

Thank you for the exposure on the NC252MP...... all amps shipping now wire the XLR pin #1 and XLR case to chassis ground, a small difference.

Welcome to ASR. I really like your faceplate style - and cool logo. It is nice to have a budget Hypex finished amp vendor/assembler in the U.S.

If I didn't already have a Ghent case for ICEpower 200ASC modules , I would buy a mono plus a stereo NC25xMP from you.

Can you address the issue with the duct tape wrapped around a Molex connector in the picture on page two that I am re-posting here? It apparently works, but causes raised eyebrows.

 

[stunta]

Thank you for the exposure on the NC252MP...... all amps shipping now wire the XLR pin #1 and XLR case to chassis ground, a small difference.

Great to have you on here. If VTV could improve its build quality based on recommendations here at ASR, I will definitely consider buying from you if the need arises. I will also be able to recommend it to my friends/family. US based, good pricing, good build == hard to beat.

 

[rebbiputzmaker]

Welcome to ASR. I really like your faceplate style - and cool logo. It is nice to have a budget Hypex finished amp vendor/assembler in the U.S.

If I didn't already have a Ghent case for ICEpower 200ASC modules , I would buy a mono plus a stereo NC25xMP from you.

Can you address the issue with the duct tape wrapped around a Molex connector in the picture on page two that I am re-posting here? It apparently works, but causes raised eyebrows.

View attachment 64132

It’s pretty obvious why the duct tape is there! Think?

 

[Trouble Maker]

It’s pretty obvious why the duct tape is there! Think?

 

[VTV Amplifier]

It’s pretty obvious why the duct tape is there! Think?

Yes, I began adding tape to ensure the cable would not work its way loose. That ten pin connector only uses a few of the pins so it is not as secure as a ribbon cable otherwise. I haven't had any work loose in shipping but I wanted to eliminate the possibility. I now use black Tesa tape (although practically speaking it serves the same purpose). I'll point out it has no effect on operation, purely to provide a tighter fit in the connector.

 

[rebbiputzmaker]

Yes, I began adding tape to ensure the cable would not work its way loose. That ten pin connector only uses a few of the pins so it is not as secure as a ribbon cable otherwise. I haven't had any work loose in shipping but I wanted to eliminate the possibility. I now use black Tesa tape (although practically speaking it serves the same purpose). I'll point out it has no effect on operation, purely to provide a tighter fit in the connector.

Thank you for your answer! It is sad though that it had to be asked because some people here like to denigrate others, especially it seems other manufacturers if they’re not part of the gang.

I’ve had connectors, boards, etc, come loose durring shipping. Packages are handled so roughly by carriers sometimes it’s a miracle that they’re not destroyed during shipping. Someone in your position shipping across the country or across the world has nothing but headaches worrying if your items get to their destination safely and working.

 

[Habu]

Hi VTV Amplifier
Welcome to ASR

 

[CDMC]

Thank you for your answer! It is sad though that it had to be asked because some people here like to denigrate others, especially it seems other manufacturers if they’re not part of the gang.

I’ve had connectors, boards, etc, come loose durring shipping. Packages are handled so roughly by carriers sometimes it’s a miracle that they’re not destroyed during shipping. Someone in your position shipping across the country or across the world has nothing but headaches worrying if your items get to their destination safely and working.

I remember years ago watching as the UPS threw my turntable (which had in writing fragile all over and what side up) out the back of the truck on the ground. When I confronted him his response was "well if that would damage it, it would have already been damaged in transit". It makes you wonder how much damage occurs just because of not caring.

 

[Xulonn]

It is sad though that it had to be asked because some people here like to denigrate others, especially it seems other manufacturers if they’re not part of the gang.

Wow! Yet another lame and inaccurate value judgement. Do you understand that some people like neatness and craftsmanship inside and out of a n audio component that reflects pride in workmanship? You may find shoddy workmanship appealing or perhaps not notice it, but many people like to see a reflection of pride in workmanship by a craftsman inside and out. (However, if you are into pro audio - especially stage productions - I can understand your sense of aesthetics - that's a whole 'nuther world.)

Admiring craftsmanship and design is not directly related to sound, but an attractive front panel with a cool logo that was more than just a chunk of plain aluminum was indeed part of the reason that I was first attracted to the VTV amplifiers. VTV is apparently the first entry-level Hypex amp seller in North America. VTV ampifiers are assembled in the U.S. by a small shop with an apparently honest owner who believes in customer service. These amplifiers are very reasonably priced, and the model discussed in this thread is being enthusiastically recommended by the OP in spite of minor issues.

I asked the question about the duct tape - normally used for fixing problems and not as an electronics assembly production method - to give the owner of VTV an opportunity to explain what is a tacky-looking, but obviously a practical solution to a potential problem that could occur in shipping and handling. Given the reputation of duct tape, that fix appears to be a shoddy-looking patch. While not an elegant solution, the duct tape should in no way affect the performance of the amplifier. IMO, a drop of thick silicone adhesive, for example, would have looked much nicer - and clearly telegraphed its purpose. Trivial? Yes - but attention to detail helps sales - and I assume that achieving sales goals is important to most companies.

So bottom line, VTV offers North American audio enthusiasts - for very reasonable prices - a wide range of Hypex amplifiers in what appear to be custom Ghent cases. They should perform just like any other Hypex basic amplifier (meaning extremely well), and custom buffers are available for their more expensive Ncore and Purifi versions. The VTV website is simple, attractive, and easy to navigate, and shipping in the U.S. is free. And if I wasn't already invested in a DIY Ghent/ICEpower pair of amplifiers with similar ratings, I would definitely consider a pair of VTV amplifiers for my three-channel setup.

 

[Nathan_A]

That there is enough room to wrap the connector in tape and still have it fit into the shroud of the receiving side is a decent indicator that the wrong connector is being used on the cable end.

If the correct cable-end connector were being used there, the addition of the tape should create undue strain on the plastic of the board-side connector which could ultimately result in the walls of the connector cracking off (though probably not in this case because there's barely any environmental stress on the thing for this application).

Now, I don't know if this is Hypex spec'ing the wrong connector, or if it's VTV sourcing the wrong connector, or if it's the supplier supplying the wrong connector, but looking at that picture it seems to me like the wrong connector is being used on the cable.

 

[Xulonn]

it seems to me like the wrong connector is being used on the cable

I know nothing about the characteristics of molex connectors, but as an former technical salesman in the aerospace industry, I'm curious about this.

Are some Molex connectors designed for a loose fit and no snap-latch, and thereby dependent on pin friction to stay connected? (Looking at the photo, there appears to be a slot in the connector - is that for a guide? Or a snap-latch?)

Did Hypex spec a connector with not enough wires/pins to create enough friction to ensure a secure connection? Or do other models use all of the pins and provide more friction? Or in this day of cheap Chinese sub-components, is QC so bad that good fits are rare?

 

[CDMC]

It appears the connector is the one provided by Ghent Audio, which they state is "compatible connectors for Hypex H-connectors, exactly according to official datasheet". Their photos do not show a clip, so it appears it is designed as a friction fit.

https://www.ghentaudio.com/cable/hypex-nc502mp.html