Buckeye Amps: Hypex NCx500 Official Thread

[Buckeye Amps]

Will the standby feature be available as a retrofit for 2ch Hypex NCx500?

At this time it would only be a feature with the Micro Audio SMPS'

 

[amper42]

It will be, yes. But no timeframe/ETA. It is part of something that will be tested and implemented as we slowly work on incorporating Micro Audio SMPS' to more of our products in place of many of the Hypex SMPS' options.

Is there a way to make sure you don't get the "Micro Audio SMPS" when ordering a Buckeye amp so you don't have to deal with the high idle power drain that doesn't stop unless the power switch is turned off?

The order pages that I see represent that the NCx500 comes with a Hypex SMPS1200A700. Is there anyway to update order pages before changing the PS component used? Thank you!

 

[Buckeye Amps]

The amps using a Micro Audio SMPS are marked as such. Which are the 3ch NCx and the Mono 7040SA.

Ironically those will be the first amps outside the NCxxxMP series that will have true standby control and minimal power draw in the coming weeks/months.

 

[MicroAudio]

Is there a way to make sure you don't get the "Micro Audio SMPS" when ordering a Buckeye amp so you don't have to deal with the high idle power drain that doesn't stop unless the power switch is turned off?

The order pages that I see represent that the NCx500 comes with a Hypex SMPS1200A700. Is there anyway to update order pages before changing the PS component used? Thank you!

Who told you that the SMPS1200A700 power draw in standby mode is 0 W?

Did you measure the power draw of the SMPS1200A700 by yourself before making any claims?

SMPS2K draws 0.1W or less in standby mode.

It's better you support your claim with evidence next time.

Thanks

 

[amper42]

Who told you that the SMPS1200A700 power draw in standby mode is 0 W?

Did you measure the power draw of the SMPS1200A700 by yourself before making any claims?

SMPS2K draws 0.1W in standby mode.

It's better you support your claim with evidence next time.

Thanks

Dear MicroAudio,
It looks like you didn't read message #443 above in this thread where users are reporting 38W while on and 21W while in auto mode with the Micro Audio SMPS? In message #445 Dylan explains Buckeye is installing the Micro Audio SMPS but doesn't have "a proper design/pinout in place to handle the Micro Audio SMPS Standby feature." He further explained that it is only being used in "the 3ch NCx and the Mono 7040SA" currently.

So while the Micro Audio SMPS may have a low standby power draw with a proper Standby design that's not what's happening in currently shipping Buckeye amps with this SMPS. I hope that explains the issue.

 

[MicroAudio]

Dear MicroAudio,
It looks like you didn't read message #443 above in this thread where users are reporting 38W while on and 21W while in auto mode with the Micro Audio SMPS? In message #445 Dylan explains Buckeye is installing the Micro Audio SMPS but doesn't have "a proper design/pinout in place to handle the Micro Audio SMPS Standby feature." He further explained that it is only being used in "the 3ch NCx and the Mono 7040SA" currently.

So while the Micro Audio SMPS may have a low standby power draw with a proper Standby design that's not what's happening in currently shipping Buckeye amps with this SMPS. I hope that explains the issue.

@amper42

I did.

But using different SMPS in place of the SMPS 2K won't change or affect the power draw in trigger mode or auto mode.

Thank you.

 

[Buckeye Amps]

Also, I misspoke days ago. We do have the proper pinout in place for doing standby control of the Micro Audio SMPS. Just need to do some testing (which is being done while we finalize the Purifi 9040BA amp) and most likely can be implemented with a simple firmware update.

 

[Heyu]

I'm confused about the gain stage on the NXC500. Can you change it without connecting an av receiver or dac? It mentions Hypex and Buckeye gain.

 

[Buckeye Amps]

I'm confused about the gain stage on the NXC500. Can you change it without connecting an av receiver or dac? It mentions Hypex and Buckeye gain.

Yes. The Buckeye gain stage has three different settings changed via toggle switch on the back.

The Hypex gain stage has a set gain.

 

[Heyu]

What's the difference between the mono and stereo since specs seem the same and they sound the same?

 

[Buckeye Amps]

What's the difference between the mono and stereo since specs seem the same and they sound the same?

Max power is a little higher on the mono (website needs updated for the 2ch to reflect this) but the difference is an inaudible difference (less than 1dB).

Monoblocks are mainly targeted for those who like to have an amp near each L/R (and sometimes Center) speaker.

 

[Heyu]

Max power is a little higher on the mono (website needs updated for the 2ch to reflect this) but the difference is an inaudible difference (less than 1dB).

Monoblocks are mainly targeted for those who like to have an amp near each L/R (and sometimes Center) speaker.

I see thank you. Also this may be a dumb question but using a preamp with this amp will the preamp take away from the sound quality?

 

[Buckeye Amps]

I see thank you. Also this may be a dumb question but using a preamp with this amp will the preamp take away from the sound quality?

Any good preamp will not negatively affect the sound quality.

 

[Heyu]

What is the filter capacitance as far as the spec on that?

 

[DonH56]

What is the filter capacitance as far as the spec on that?

This is NOT directed at you, but rather a general comment on the question, as it comes up often.

Filter (decoupling) capacitance is one of those things audiophiles ask and marketeers sell but has little impact in real life except when the caps are poor quality and fail early. Another "bigger is better" metric ignoring all the other trades.

Switched-mode power supplies (SMPS') require much smaller capacitors than conventional "linear" power supplies because SMPS operate at frequencies orders of magnitude higher. For example, a typical linear supply recharges the capacitors 120 times a second (120 Hz), whilst an SMPS works from 100 kHz to >1 MHz. There is far less time for capacitors to discharge before the supply "tops them off" so much smaller capacitors can be used. For example, for the same output current and voltage sag, 1000 uF at 120 Hz becomes 1.2 uF at 100 kHz. That makes comparing capacitance among different amplifier types tricky; the one with 100 uF in a 100 kHz SMPS actually has much more effective charge storage than 10,000 uF in a conventional supply relative to supply voltage sag.

 

[LSUGopher]

I currently have a Buckeye 3 channel NCx500 on order and am contemplating changing it to a ET400A model. I have a few questions hopefully some Buckeye three channel ET400A or NCx500 owners can answer.

• There have been multiple accounts of the purifi ET400A amps running cool and the Hypex NC502MP models running much hotter. Anyone that a 3 channel NCoreX owner can comment on their experience with case heat? How hot does it get? My theater/music area is in a room over a garage and gets quite hot during the Louisiana summer afternoons and I am looking to minimize extra heat generation inside the room where I can.
  • The idle load of the 3 channel NCx500 model is reported by one user to be 38 watts while the idle loads of the ET400A 3-channel are likely to be around half that. That will help with heat generation and the low idle watts of the ET400A modules are likely why they run so cool.
  • From the Hypex/Purifi datasheets: SMPS1200 has 9 watts idle loss and the ET400A idle loss is 1.7 watts/channel so the Buckeye three channel ET400A model should have a loss of 14 idle watts.
  • Per the Hypex datasheet, NCx500 have an idle loss of 5.3 watts/channel which sums to 16 watts. Since the idle loss reported is currently 38 watts then the 2k Microaudio SMPS has idle losses of 22 watts (its datasheet from what I could tell is not publically available). That does seem a bit high as the Hypex 3k SMPS has idle losses of 15 watts and the Microaudio 2k in theory should be somewhere in between that and the 9 watts of the SMPS1200.
  • As a point of reference the 4 channel NC502MP per the Hypex datasheet has an idle loss of 53 watts (17 watts per SMPS (2) and 4.8 watts per channel (4))

• I have seen prior pictures of the NCx500 module red LED lights shining through the case. For anyone that uses a Buckeye NCx500 amp, is this noticeable in a dark room when watching movies? I’ll probably have 5-7 inches of room between the top of the amp and the shelf above so I believe any light will be visible coming out of the vent and be a distraction.

The amp will be used to drive Ascend Acoustics ELX towers/Horizon LCR speakers. They are advertised as 8 ohm nominal, but the impedance dips down to ~4 ohms from 90-300 Hz. I don't think are considered a very difficult load (I attached the impedance chart below) They are also rated for up to 400 watts max continuous power so they could take advantage of the extra watts of the NCx500. I generally watch movies around at around -7 to -10 dB, and listen to music around 85-95 dB so from the SPL calculations I have done either model ET400A or NCx500 should work well. The NCx500 has a decent amount more wattage into 8 ohm loads which is why I initially picked it over the ET400A, but if the heat/red light leakage are significant disadvantages then I may switch to the ET400A model.

Thanks for any experiences you can share.

 

[ryanosaur]

I have seen prior pictures of the NCx500 module red LED lights shining through the case. For anyone that uses a Buckeye NCx500 amp, is this noticeable in a dark room when watching movies? I’ll probably have 5-7 inches of room between the top of the amp and the shelf above so I believe any light will be visible coming out of the vent and be a distraction.

I have 5 NC400 amps running in Ghent Chassis... yes different, but the red LEDs are still utilized and I don't see them outside the Chassis.

 

[Buckeye Amps]

• • Per the Hypex datasheet, NCx500 have an idle loss of 5.3 watts/channel which sums to 16 watts. Since the idle loss reported is currently 38 watts then the 2k Microaudio SMPS has idle losses of 22 watts (its datasheet from what I could tell is not publically available). That does seem a bit high as the Hypex 3k SMPS has idle losses of 15 watts and the Microaudio 2k in theory should be somewhere in between that and the 9 watts of the SMPS1200

This is being rectified with Standby control of the Micro Audio SMPS and the entire amplifier section.

 

[MicroAudio]

SMPS2K idle losses without anything connected is 10.5W.

SMPS is ON and all output voltages are available.

SMPS in standby power consumption is 0.2W.

 

[LSUGopher]

@ryanosaur, Thanks for sharing your experience with the red leds on your Hypex amps.

@MicroAudio, Thanks for sharing the actual idle/standby power consumptions. 10.5 watts for 2k is pretty good. I had assumed somewhere around 12 watts based on the Hypex 1200 and 3000 SMPS idle watts

@Buckeye Amps, My question was more around power consumption when the amp is on, but not working very hard (current wattage requirements are low). I am assuming that an amp with a lower idle wattage would run cooler in that scenario than one with a higher idle wattage. I don't know if that would make a meaningful difference between the Buckeye 3 channel ET400A/NCx models, which is why I posed the question. I also think updating the design to allow true standby operation is a great update, which is a plus over the Purifi models (I assume that isn't incorporated currently). If possible I think you should try to add that feature to all of your models. Lastly, the firmware upgrade to allow standby control, can that be done by the end user or would it need to be returned to you? Do you expect that feature to be implemented by the time the next 2k MA SMPS arrive for the 2024 orders?