[Julf]

It should take only a few minutes to switch to 8 Ohm load to directly compare.

That is still much longer than human auditory short-term memory, so it won't be a "direct" comparison.

[Ric Schultz]

What? I can remember years later......you simply do not trust yourself nor your experience.

If you have a reliable constant reference then you can easily discern differences.....even day to day.

Some years ago I put on the first Stereophile test disc after not hearing it for several years......different systems in each case.  Clearly did not sound as good as before......yes, I remembered.  So, I tweaked the speakers and there it was......much better sound.  You can remember!  You can hear!  You can discern differences!  Yes, it does not take a "Golden Eared One".  Anyone can do it......but you have to actually listen with an open mind to a very tweaky system.

[James Romeyn]

Humor me for a moment.

Do you hear differences between components/speakers in their ability to accurately portray pitch? 

Forgive me for stating what might be obvious, but harmonic overtone structures determine differences between a flute (closest to sine wave, few harmonics) and violin (sawtooth waveform, all multiples of the fundamental and high in level).  These are direct mathematical relationships of which we speak. 

The higher is pitch sensitivity in the entire chain (from the instrument to the ears and everything in between) the more easily is pitch perceived.  The more is pitch perceived the greater is the illusion maintained and the lower is the listener's stress level (less brain activity required for a given magnitude of illusion). 

Can you tell if one instrument is more closely tuned to pitch than another?  Presume one guitar is tuned for John Williams (guitarist, not the schlock movie score composer), the other by a not so great 12 year old guitarist.  These are extreme examples only to make the point.

Would you necessarily need only a brief time period between hearing the two guitars to know one is tuned closer to proper pitch?     

[Julf]

Do you hear differences between components/speakers in their ability to accurately portray pitch?

None of my speakers or systems distort pitch in any way - they reproduce pitch accurately. They might not reproduce amplitude relations between harmonics totally accurately, but they do not distort pitch.
 

Would you necessarily need only a brief time period between hearing the two guitars to know one is tuned closer to proper pitch?     

No, because an error in guitar tunings are reflected in incorrect pitch relationships that are audible without reference to any other sound, because a guitar tuning is not an absolute thing, it is a relation between the strings of the guitar, so you reference the pitch of each string against the pitch of the other strings, not against something you have to retain in your memory. A change in *colour* (in terms of frequency response or distortion) isn't referenced to anything except you recollection, so is harder to detect after a delay.

[James Romeyn]

None of my speakers or systems distort pitch in any way - they reproduce pitch accurately. They might not reproduce amplitude relations between harmonics totally accurately, but they do not distort pitch.
 
No, because an error in guitar tunings are reflected in incorrect pitch relationships that are audible without reference to any other sound, because a guitar tuning is not an absolute thing, it is a relation between the strings of the guitar, so you reference the pitch of each string against the pitch of the other strings, not against something you have to retain in your memory. A change in *colour* (in terms of frequency response or distortion) isn't referenced to anything except you recollection, so is harder to detect after a delay.

Pitch is referenced to the fundamental apart from the harmonics.  The notes on the music staff reference the fundamental and are oblivious to harmonics.  But harmonics are direct mathematical multiples of the fundamental.  So this begs the obvious question: in audio, exactly how can harmonic distortion be compartmentalized separately from the fundamental?  I doubt the two are separate from each other.  If the two are intertwined (how can they not be?), then HD and pitch are interrelated.

Toole knows a few things about this.  He posits one of the benefits of improved reverberant field is improved pitch sensitivity.  The ear gets a "second look" at the pitch (Geddes says ideally 10-20ms later), thus solidifying the first on-axis impression.  IMO this "second look" at the pitch also lowers stress and increases the illusion of live music.  Over the past 1.5 years I've had the luxury of turning on-off the reverberant field section of my loudspeaker.(which comprises two separate full range speakers per ch).   

Perhaps one could envision the orchestra and chorus of Beethoven's 9th or a huge Wagner piece and imagine all these instruments playing inter related pitches, and imagine that there is more to pitch portrayal than is commonly believed to be the case. 

Regarding the two guitars, I asked if time passing would affect one's ability to judge which guitar was more properly tuned vs. the other, or meant to if I did not.   

[James Romeyn]

I asked:

Do you hear differences between components/speakers in their ability to accurately portray pitch? 

Followed by:

None of my speakers or systems distort pitch in any way - they reproduce pitch accurately.

If I was hard pressed to state whether your reply is closer to "yes" or "no," I'd have to guess "no."

[Julf]

Regarding the two guitars, I asked if time passing would affect one's ability to judge which guitar was more properly tuned vs. the other, or meant to if I did not.

And i answered, or meant to, that the tuning of one guitar string is referenced relative to the other strings. You don't compare the tuning against a remembered acoustic picture, you listen for harmonic intervals. When comparing two reproduction systems you don't have that reference, and are forced to rely on auditive memory.

Anyway, that has nothing to do with bridging.

You are claiming and suggesting a bunch of things that contradicts what Hypex (the designers and manufacturers of the modules) are saying. I think I prefer to believe Bruno and the Hypex technical people, as they ought to be the ones who know their own modules.

[gstew]

I made, well, a lot of NC400 single mono/SMPS600 and stereo/SMPS1200.  For reasons relating to cost and performance above the bass range, some time ago I "downgraded" from single NC400 to my old standby analog chip amps.

James,

I'm wondering how much of the difference is the SMPS600 versus the SMPS1200. Do you have experience with single or dual NC400s with each of these SMPS's and whether you heard any differences?

TIA!

Greg in Mississippi

[Tomy2Tone]

Bump.

Just curious if anyone else out there has heard a bridged nc400 mono block lately and compared it to standard version.

I have yet to listen to a nc400 amp but hope to someday, so just wondering if bridging is worth it for these amps.

[Julf]

I have yet to listen to a nc400 amp but hope to someday, so just wondering if bridging is worth it for these amps.

Bridging is worth looking at if you need more power and have speakers with an impedance that doesn't drop too low, but otherwise it doesn't make any sense.
 

[Tomy2Tone]

Bridging is worth looking at if you need more power and have speakers with an impedance that doesn't drop too low, but otherwise it doesn't make any sense.

Thanks for the reply.

I have some speakers coming that are a 3 way design with 87db sensitivity and 4ohm nominal.

Do you think they could benefit from a bridged nc400 mono pair? I do like to play loud at times.

[Julf]

I have some speakers coming that are a 3 way design with 87db sensitivity and 4ohm nominal.

Do you think they could benefit from a bridged nc400 mono pair? I do like to play loud at times.

87 dB/1W means 113 dB/400W. That is pretty darn loud.... So no, I don't think you need bridging.

My Isobariks have a sensitivity of 86 dB, and we have our own house, so I can enjoy really loud levels if I want to - and I have never yet reached full volume on the volume control.

4 ohm nominal could mean too low at the lowest impedance points.