Just one picture...
An externally hosted image should be here but it was not working when we last tested it.
The hypex input is differential in any case. It doesn't really matter much whether the driving circuit (DAC output) is differential or not (apart from a possible difference in voltage/gain).
Hey all,
Sorry if this is the wrong place to post this, I just didnt want to start a new thread as this looked like a good place to ask.
Does everyone enjoy their Ncore amps so far?
I have read that Class D amps, the Ncore in particular can sound "different" to Class A amps. I am assuming this is simply because of the rediculously small amount of distortion that these amps create and not color the sound...is this correct?
I am very interested in building a dual mono one of these to try out.
Has anyone compared these to the F5 or F5 Turbo?
Sorry if this is the wrong place to post this, I just didnt want to start a new thread as this looked like a good place to ask.
Does everyone enjoy their Ncore amps so far?
I have read that Class D amps, the Ncore in particular can sound "different" to Class A amps. I am assuming this is simply because of the rediculously small amount of distortion that these amps create and not color the sound...is this correct?
I am very interested in building a dual mono one of these to try out.
Has anyone compared these to the F5 or F5 Turbo?
Everybody will have their own opinion, but yes, technically the specs of the ncores are pretty outstanding, but they are also at a level where it is hard to hear any differences between them and other top-spec amps, and factors such as the low output impedance / high damping factor / high current capability become more important.
The answer might be far more complex, IMO. Has any one thoroughly measured 400kHz switching residuals, how they spread through mains power cables and signal cables, if they affect as intermodulation products audio band signals, especially in connection with digital signal sources with high HF interference content at their output.
Oh no. I require for my system to be completely resistant to cellular phone ringing, contactor switching, PC connected, TV with SMPS and DVD with SMPS. These issues must not audibly affect the signal. If they do, what are the perfect parameters of single component good for?
I asked this question many pages ago - the Ncore has several hundred millivots @500kHz at the speaker's output. IME with a different class D amp, this made listening to a turntable in my room very unpleasant, whether the amp was actually in use, or just idling. The design of my arm makes shielding impossible, so there is a readily available point of entry for RF.
The good old advice of not running speaker cables parallel to unshielded signal leads is still a good one - as well as the hypex recommendations for proper twisting of cables.
Do you also have issues with the PC power supplies, dimmers, mobile phone chargers etc. mentioned earlier?
If you mean SET type class A in particular, then most likely yes, there will be a difference, as SET amps have a very pronounced distortion profile.
None that are obvious. Switching off all these makes listening to LPs slightly more enjoyable - better soundstage depth perhaps.
The class D amp seems orders of magnitude worse in its effects. My initial intention was to use it in a mains regenerator for one of my turntables AC motor. Tried it also as an audio amp and quite liked it with a digital source.
And two photos of inside:
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
My built - finally find some time to complete it 
Signal line change wire to MOGAMI 2534.
AC line - change wire guage to 16 (or maybe 14, can't remember).
DC line - no change. Too maybe wires involve, too lazy.
Signal line change wire to MOGAMI 2534.
AC line - change wire guage to 16 (or maybe 14, can't remember).
DC line - no change. Too maybe wires involve, too lazy.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
My Experience with Hypex NC400 Amplifier
During my college years from '71 – '79 I spent money on high-end audio equipment even if it jeopardized my budget for purchasing food. I started out with a Scott 477 receiver, a Benjamin Miracord 50H turntable and a pair of KLH Model 23 speakers. From there I moved to a Crown DC-300A power amp, IC-150 preamp, Thorens TD-125 turntable with a Shure SME 3009 tonearm equipped with a V15 type III phono cartridge, and a McIntosh MR77 tuner & ML-1C speakers. I made various transitions along the way: Dynaco Stereo 70 tube amp, AR-a & AR-3a speakers, EPI 100 & 201 speakers, and Hafler DH-101 preamp built from a kit. I sold all of my equipment at an incredibly low price sometime near 1982 and have lived with nothing more than table radios and portable tape & CD players since. Just recently, after 30 years of abstinence, I decided to investigate the state of affairs of high-end audio equipment. Somehow I stumbled upon preamplifier kits sold on eBay that were modeled after highly successful vintage amplifiers. This interested me because my BS degree was in Electrical Engineering Technology. Upon further investigation, I ended up in several do-it-yourself (DIY) audio forums where people (some were well-respected audiophile journalists) were praising the Hypex NC400 power amplifier. I reasoned that too many individuals from different corners of the earth could not all be deceived in their belief that the NC400 was the best (or near the best) amplifier that they ever encountered. What amazed me and attracted me was the idea that a DIY kit produced in the Netherlands had become a serious competitor to professional preassembled amplifiers costing considerably more. So, I decided to take the plunge. Here is my actual order from Hypex:
Amt Product Unit-price Line-total
2 NC400 USD 441,40 USD 882,79
1 SMPS1200A400 USD 203,72 USD 203,72
1 Cable set SMPS1200 USD 13,58 USD 13,58
Shipping USD 32,86
Payment-costs USD 0,00
VAT USD 0,00
Total USD 1132,96
When the package arrived, I had to give the UPS delivery man a $60.90 check made payable to Hypex Electronics for a "brokerage fee" which I presumed was a customs fee. Whether this is a tariff imposed by the U.S. government on Dutch imports or an export fee imposed by Netherlands, I do not know. I ordered a case to house my stereo amplifier from Siliconray which arrived 3 weeks later:
RE2507-NC enclosure for 2 channels Hypex NC400 1 $135.00
Subtotal $135.00
Shipping & Handling $10.00
Grand Total $145.00
The build would have been easier if I ordered two separate power supplies but I decided to save some money by using a single larger PS to run both amps. I wired my power supply according to this schematic: SOLVED: NC400+SMPS1200A400 - no sound
At first, I ran the amplifier without a fan but decided that it was simply too hot for long-term reliability. Alan Moore of Moore Machine & Gear kindly offered to cut a hole in my case for free using his very expensive milling machine so that I could mount a 120mm computer fan. I was delighted that the case had ample room to mount the fan inside without contacting the amplifiers. I ran the fan at half its 12V DC rating using a spare 6V DC adapter which reduced the fan speed and noise. I tucked the adapter neatly into the front of the case. The hottest part of the case is now room temperature while other parts feel cold. The fan is barely audible at a 3-foot distance—a small price to pay for what I gained in lower temperatures & reliability:
Later, I reduced the fan noise even further by installing an Austrian-designed Noctua NF-S12A FLX fan. It isn't as pretty as the former fan with LED lights but I'll sacrifice lights & color for sound. When I mounted the Noctua fan, I realized that I could mount the protection grill inside the case instead of the outside for a cleaner look:
To compliment the NC400 stereo amplifier, I purchased an Oppo BDP-105 Blu-ray player which can play about anything except vinyl disks. It has balanced XLR outputs that are sufficient to drive my NC400's without a preamp. Controlling the volume is accomplished via the Oppo's remote control. I actually enjoy this arrangement much more than what I was accustomed to earlier when I used a preamplifier with balance, bass, treble, loudness, mute, and various input/output switches that degraded the sound and required me get off my couch and manually turn the volume knob. After much research, I chose the Definitive Technology SM65's for my speakers.
Listening Impressions
My first impression was that the majority of my old compact disks were poorly recorded. I noticed an excessive amount of cymbal and snare drum sibilance on Shenia Twain's "Come on Over" and felt that it was NOT being produced by my amplifier or speakers. I verified this when I listened to my headphones plugged into the Oppo's headphone output. The same ear-fatiguing sibilance was present. I switched back to the speakers and tried Emerson, Lake, & Palmer's "In the Beginning". The guitar strings were the best I had ever heard on any system but I felt that I could do even better if I played some lossless digital source that was recorded with a high sampling rate. I located exactly what I was looking for: "Best Audiophile Voices" 24bit/192KHz which included Alison Krauss, Selena Jones, Al Somma and others with only acoustic instruments (e.g. bass violin instead of bass guitar, soft-sounding jazz-style snare drums, acoustic guitars with microphones as opposed to magnetic pickups, etc.) I put the flac files of these digital recordings onto a USB flash drive and plugged it into the Oppo's rear USB port. What I heard was astounding. The bass was super-tight and the midrange & highs were liquid smooth. I immediately concluded that the best sound system I ever heard in my life was my own. I became giddy. After listening to this system for about a month, I haven't changed my mind. My brother wanted to hear Sly & the Family Stone "Dance to the Music". He was highly impressed when he heard it years earlier on a pair of AR-3a's coupled to a Dynaco Stereo 400 cranked up as high as it could go without causing the amp to clip. I didn't have the original vinyl recording so I located it on YouTube in HD format:
Sly & The Family Stone - Dance To The Music (Audio) - YouTube
My speakers measure 3.9 ohms with an ohm meter so I figure my amp should approach 400W RMS/channel if the speaker impedance doesn't change appreciably under dynamic conditions with counter-EMF produced by the moving voice coils. I cranked it up crazy loud and we were all extremely impressed. My brother thought the bass on the AR-3a's 12" woofers may have been slightly stronger than my Definitive's 5.25" drivers in combination with its 12"x6" passive bass radiator, but other than that, the Definitives were superior in every respect. The bottom line is this: I couldn't be happier with my NC400 stereo amplifier. It exceeded my expectations in nearly every respect: efficiency, small size, quality of construction with surface-mount components, low background noise, low distortion, and gobs of power. Bruno Putzeys has made a HUGE contribution to the audiophile community.
During my college years from '71 – '79 I spent money on high-end audio equipment even if it jeopardized my budget for purchasing food. I started out with a Scott 477 receiver, a Benjamin Miracord 50H turntable and a pair of KLH Model 23 speakers. From there I moved to a Crown DC-300A power amp, IC-150 preamp, Thorens TD-125 turntable with a Shure SME 3009 tonearm equipped with a V15 type III phono cartridge, and a McIntosh MR77 tuner & ML-1C speakers. I made various transitions along the way: Dynaco Stereo 70 tube amp, AR-a & AR-3a speakers, EPI 100 & 201 speakers, and Hafler DH-101 preamp built from a kit. I sold all of my equipment at an incredibly low price sometime near 1982 and have lived with nothing more than table radios and portable tape & CD players since. Just recently, after 30 years of abstinence, I decided to investigate the state of affairs of high-end audio equipment. Somehow I stumbled upon preamplifier kits sold on eBay that were modeled after highly successful vintage amplifiers. This interested me because my BS degree was in Electrical Engineering Technology. Upon further investigation, I ended up in several do-it-yourself (DIY) audio forums where people (some were well-respected audiophile journalists) were praising the Hypex NC400 power amplifier. I reasoned that too many individuals from different corners of the earth could not all be deceived in their belief that the NC400 was the best (or near the best) amplifier that they ever encountered. What amazed me and attracted me was the idea that a DIY kit produced in the Netherlands had become a serious competitor to professional preassembled amplifiers costing considerably more. So, I decided to take the plunge. Here is my actual order from Hypex:
Amt Product Unit-price Line-total
2 NC400 USD 441,40 USD 882,79
1 SMPS1200A400 USD 203,72 USD 203,72
1 Cable set SMPS1200 USD 13,58 USD 13,58
Shipping USD 32,86
Payment-costs USD 0,00
VAT USD 0,00
Total USD 1132,96
When the package arrived, I had to give the UPS delivery man a $60.90 check made payable to Hypex Electronics for a "brokerage fee" which I presumed was a customs fee. Whether this is a tariff imposed by the U.S. government on Dutch imports or an export fee imposed by Netherlands, I do not know. I ordered a case to house my stereo amplifier from Siliconray which arrived 3 weeks later:
RE2507-NC enclosure for 2 channels Hypex NC400 1 $135.00
Subtotal $135.00
Shipping & Handling $10.00
Grand Total $145.00
An externally hosted image should be here but it was not working when we last tested it.
The build would have been easier if I ordered two separate power supplies but I decided to save some money by using a single larger PS to run both amps. I wired my power supply according to this schematic: SOLVED: NC400+SMPS1200A400 - no sound
At first, I ran the amplifier without a fan but decided that it was simply too hot for long-term reliability. Alan Moore of Moore Machine & Gear kindly offered to cut a hole in my case for free using his very expensive milling machine so that I could mount a 120mm computer fan. I was delighted that the case had ample room to mount the fan inside without contacting the amplifiers. I ran the fan at half its 12V DC rating using a spare 6V DC adapter which reduced the fan speed and noise. I tucked the adapter neatly into the front of the case. The hottest part of the case is now room temperature while other parts feel cold. The fan is barely audible at a 3-foot distance—a small price to pay for what I gained in lower temperatures & reliability:
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Later, I reduced the fan noise even further by installing an Austrian-designed Noctua NF-S12A FLX fan. It isn't as pretty as the former fan with LED lights but I'll sacrifice lights & color for sound. When I mounted the Noctua fan, I realized that I could mount the protection grill inside the case instead of the outside for a cleaner look:
An externally hosted image should be here but it was not working when we last tested it.
To compliment the NC400 stereo amplifier, I purchased an Oppo BDP-105 Blu-ray player which can play about anything except vinyl disks. It has balanced XLR outputs that are sufficient to drive my NC400's without a preamp. Controlling the volume is accomplished via the Oppo's remote control. I actually enjoy this arrangement much more than what I was accustomed to earlier when I used a preamplifier with balance, bass, treble, loudness, mute, and various input/output switches that degraded the sound and required me get off my couch and manually turn the volume knob. After much research, I chose the Definitive Technology SM65's for my speakers.
An externally hosted image should be here but it was not working when we last tested it.
Listening Impressions
My first impression was that the majority of my old compact disks were poorly recorded. I noticed an excessive amount of cymbal and snare drum sibilance on Shenia Twain's "Come on Over" and felt that it was NOT being produced by my amplifier or speakers. I verified this when I listened to my headphones plugged into the Oppo's headphone output. The same ear-fatiguing sibilance was present. I switched back to the speakers and tried Emerson, Lake, & Palmer's "In the Beginning". The guitar strings were the best I had ever heard on any system but I felt that I could do even better if I played some lossless digital source that was recorded with a high sampling rate. I located exactly what I was looking for: "Best Audiophile Voices" 24bit/192KHz which included Alison Krauss, Selena Jones, Al Somma and others with only acoustic instruments (e.g. bass violin instead of bass guitar, soft-sounding jazz-style snare drums, acoustic guitars with microphones as opposed to magnetic pickups, etc.) I put the flac files of these digital recordings onto a USB flash drive and plugged it into the Oppo's rear USB port. What I heard was astounding. The bass was super-tight and the midrange & highs were liquid smooth. I immediately concluded that the best sound system I ever heard in my life was my own. I became giddy. After listening to this system for about a month, I haven't changed my mind. My brother wanted to hear Sly & the Family Stone "Dance to the Music". He was highly impressed when he heard it years earlier on a pair of AR-3a's coupled to a Dynaco Stereo 400 cranked up as high as it could go without causing the amp to clip. I didn't have the original vinyl recording so I located it on YouTube in HD format:
Sly & The Family Stone - Dance To The Music (Audio) - YouTube
My speakers measure 3.9 ohms with an ohm meter so I figure my amp should approach 400W RMS/channel if the speaker impedance doesn't change appreciably under dynamic conditions with counter-EMF produced by the moving voice coils. I cranked it up crazy loud and we were all extremely impressed. My brother thought the bass on the AR-3a's 12" woofers may have been slightly stronger than my Definitive's 5.25" drivers in combination with its 12"x6" passive bass radiator, but other than that, the Definitives were superior in every respect. The bottom line is this: I couldn't be happier with my NC400 stereo amplifier. It exceeded my expectations in nearly every respect: efficiency, small size, quality of construction with surface-mount components, low background noise, low distortion, and gobs of power. Bruno Putzeys has made a HUGE contribution to the audiophile community.
Nice story AClarke. Thanks for sharing. It's the PSU that gets hot. Two in one small cabinet without many holes and airflow makes it more tricky.
Perhaps next move is some quality DIY speakers and a sub? Doesn't need to be expensive.
Waveguide Speaker kits DIY Sound Group
Subwoofer Flat Packs DIY Sound Group
Perhaps next move is some quality DIY speakers and a sub?
Doesn't need to be expensive.Waveguide Speaker kits DIY Sound Group
Subwoofer Flat Packs DIY Sound Group
My first impression was that the majority of my old compact disks were poorly recorded.
Yes, that is one of the perils of a revealing system. It's well to keep in mind that popular recordings are made with many different end customers in mind, and audiophiles are definitely in the minority. Enjoy your NCOREs
Yes, that is one of the perils of a revealing system. It's well to keep in mind that popular recordings are made with many different end customers in mind, and audiophiles are definitely in the minority. Enjoy your NCOREs
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