hypex ncore - Page 253 - diyAudio
Go Back   Home > Forums > Commercial Sector > Vendor Forums > Vendor's Bazaar

Vendor's Bazaar Commercial Vendors large & small hawking their wares

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 21st February 2012, 10:30 PM   #2521
diyAudio Member
 
Join Date: Sep 2003
Location: London
Off topic a bit but something I'd like to know. Has anybody in London got a finished amplifier they could demonstrate? My brother is a doctor in Fulham and has Apogee Caliper Signature speakers. Full range electrostatics with low impedance like about 4 ohms. He runs a big Krell and also a pair of Nagra 845 tube monobloks. He's definitely in the market if he likes it - I'd probably build it for him, or he might just buy a finished amp.

So - anybody in London area who could demonstrate?

Best, Andy
  Reply With Quote
Old 21st February 2012, 10:35 PM   #2522
diyAudio Member
 
Join Date: Mar 2011
Quote:
Originally Posted by ro9397 View Post
String instruments such as bass have a very rich sawtooth waveform, whose harmonics extend well up into the mid range and even the treble. Many believe, including myself (Bruno chime in!) that listeners may perceive improved mid/treble range performance as improved "bass", even if performance in the range of the bass fundamentals is unchanged.

It seems less likely listeners might perceive improved bass via improvement only in the range of bass fundamentals, for the following reason:



Again, please correct if necessary. IIRC studies support the conclusion that in the range of bass fundamentals, humans have difficulty perceiving a difference between 1% THD and 30% (yes, thirty percent) THD (modal effects caused by the room are a completely different story for many reasons).

So I'd agree with Bruno, and be interested how/why there is much difference between the two Hypex amps reproducing only below 200 Hz...
Then the question arises: why are better woofers often able to improve perceived mid and high frequency reproduction too? (of course leaving out mid/bass transition which otherwise has a lot to say as a woofer in fact will reproduce some of the midrange content).
More clearly it could be stated that if human ear cannot detect the difference between 1 and 30% THD below 200Hz, then we should not be able to hear differences between different woofers at all, if they are just EQ´ed to similar response. This would contradict my experiences and probably that of most other speaker builders.

Another type of reasoning that I might suggest is to investigate what the claim you refer to actually says, and what kind of delimitation it has been constructed upon. Hence what and what not it actually can be transferred to as being a valid fact to build further reasoning upon. My humble guess is that the way the test has been conducted (setup) is very (to vastly understate it) different to the context (setup) in which it is tried to be used as a valid argument here.

Another thing I personally find interesting about THD and audibility, is that the human ear (if properly trained) seemingly can hear the difference between very small distortion artifacts caused by an amplifier (like ncore vs UCD) when the later speaker and room causes magnitudes higher distortion (THD). Speakers are generally in the 1% and the room contribution much much more. We are talking at least a 1000 fold THD that still does not suffice to hide what the amp is causing (at least the difference of doing a little (THD > 0,1% for UCD) and very little (THD >> 0,01% ncore)).

My guess is that the human ear can be very well adapted (also if trained, of course) to distinguish distortion artifacts from each other. Like tasting or smelling subtle flavors behind much stronger spices like chili and garlic. At least when regarding taste and smell, scientific and instrumental dogmatism has not yet induced a blind rational madness as the nose and tongue of those who are trained cannot be ruled away for objective standardization. Of course sound and smell are not in the same domain as one is reproduction (in the way we are dealing with it) and the other is a primary chemical source (yet still possibly reproduced, though seldom in a truly convincing way)

That said it really IS interesting that pure active bass applications seem to yield audible benefits from using nocre over UCD´s.

At least Bruno should be thrilled -until someone starts craving a 10kW ncore for welding woofers in home-MAX-theater applications

cheers,
  Reply With Quote
Old 21st February 2012, 10:47 PM   #2523
diyAudio Member
 
Join Date: Sep 2003
Location: London
I'm a professional double bass player (kontrabass), and I'm very wary about what people expect from bass sounds. I read a lot about bass "slam". A string bass has no slam. It isn't an acoustic phenomenon. It's an amplified phenomenon. So with an electric bass and an amp you can have as much "slam" as you want - it's up to your personal taste. If you want to shake the walls - fine!

What I listen for is tone and definition - are we hearing a good acoustic note or a thud? Bass players can tell gut strings from nylon coated strings from metal strings, even at these low frequencies, but you're quite right to say that much of the definition and timbre in this case may come from higher frequencies.

But my point remains that the kind of bass that people judge to be "good" can vary hugely from one listener to another. One example - many people like subwoofers. I can't stand them and I haven't heard a single one that sounds better on than off. I'd prefer less bass but musical bass. That's where I'm coming from!!

As for "better woofers" - a 15" speaker is just about perfect for string bass, and what most of us use on stage. Though I have to say I've heard nice bass from smaller units, and increasingly bass players are using combinations of smaller units.

Andy

Last edited by andyjevans; 21st February 2012 at 11:05 PM.
  Reply With Quote
Old 21st February 2012, 11:00 PM   #2524
ro9397 is offline ro9397  United States
diyAudio Member
 
Join Date: Jan 2007
Location: No. Utah
Relative to Juhleren interesting points above:

The interaction between two speakers, a listener, and the domestic room's boundaries result in "X" perceived sound quality in the bass range. I think listeners often mistakenly associate "X" as an inherent quality whose result is 90% to 100% sourced by the speaker rather than the sum total of all the above ingredients.

Take two different woofers in enclosures, both well tuned in appropriate reflex enclosures, testing closely in THD and response. The port of one enclosure is tuned to the same frequency as one of the room's worst modal effects. The port of the other enclosure is tuned far from any modal effect. Which one will listeners prefer?
__________________
James
"Television is the poor man's whiskey." Russel Baker
  Reply With Quote
Old 21st February 2012, 11:06 PM   #2525
ChrisPa is offline ChrisPa  United Kingdom
diyAudio Member
 
Join Date: Jan 2005
Location: Saddleworth
Quote:
Originally Posted by Juhleren View Post
Then the question arises: why are better woofers often able to improve perceived mid and high frequency reproduction too?
May be as simple as the level of 2nd (3rd, 4th etc) harmonic in the thd from the bass driver is at a level where it becomes a significant part of the midrange content (and with phase effects possibly causing nulls in the upper frequencies rather than additive effects (okay, I know a null is a negative addition))

Completely remove a lower quality (higher distortion) bass driver from the system and you may get a better quality midrange. Possibly would also explain why many speakers lose control as amplitude increases - distortion is non-linear and dependent on cone excursion.

After many decades I'm still generally of the opinion that 'infinite baffle' speakers provide a better and more controlled bass than port loaded speakers where the out of phase /delayed signal from the port takes time to combine with the initial signal from the bass driver
  Reply With Quote
Old 21st February 2012, 11:35 PM   #2526
diyAudio Member
 
Join Date: Mar 2011
Quote:
Originally Posted by andyjevans View Post
But my point remains that the kind of bass that people judge to be "good" can vary hugely from one listener to another. One example - many people like subwoofers. I can't stand them and I haven't heard a single one that sounds better on than off. I'd prefer less bass but musical bass. That's where I'm coming from!!

Andy
Andy,
I too prefer non-sub´ed systems. My experience is the same as yours. More is not always better to my ears, but people differ and some even develop along the way ;-)


Quote:
Originally Posted by ro9397 View Post
Relative to Juhleren interesting points above:

The interaction between two speakers, a listener, and the domestic room's boundaries result in "X" perceived sound quality in the bass range. I think listeners often mistakenly associate "X" as an inherent quality whose result is 90% to 100% sourced by the speaker rather than the sum total of all the above ingredients.

Take two different woofers in enclosures, both well tuned in appropriate reflex enclosures, testing closely in THD and response. The port of one enclosure is tuned to the same frequency as one of the room's worst modal effects. The port of the other enclosure is tuned far from any modal effect. Which one will listeners prefer?
If your condensed statement is that implementation is much more important than the quality of the single part(s), I totally agree. This is where much DIY goes totally off track. A component is not about the sum of the parts (and their respective prices) but how they are made to perform. Good product design offers good performance from simple but well put together parts. That´s called innovation :-) Then using premium part in dedicated places may yield performance gains that justifies the higher prices for said components. Not the other way around; good parts seldom (if ever) cause a bad design to make sense.

Quote:
Originally Posted by ChrisPa View Post
May be as simple as the level of 2nd (3rd, 4th etc) harmonic in the thd from the bass driver is at a level where it becomes a significant part of the midrange content (and with phase effects possibly causing nulls in the upper frequencies rather than additive effects (okay, I know a null is a negative addition))

Completely remove a lower quality (higher distortion) bass driver from the system and you may get a better quality midrange. Possibly would also explain why many speakers lose control as amplitude increases - distortion is non-linear and dependent on cone excursion.
Good point CrisPa. Yes distortion transcendes the intended band of use. Also, this could be an argument for some of the advantages of active drive (sans passive filters), as the damping of the amp then is able to damp a driver motor throughout the entire audible band and not just where the filter allows it to. Distortion caused by say a 100 Hz fundamental (below cutoff hence little filter interaction on amplifier damping) that cause multiple distortion artifacts at higher frequencies (above cutoff hence much more filter interaction reducing the amplifiers damping).

That said, it would really surprise me if the experienced differences between woofer qualities are "only" related to mid and treble artifacts which they are believed to cause and not also to their fundamental LF performance. After all we are talking about some 80% of the power in the music signal that typically goes to the sub 200 Hz region. Our ears don´t really need to be that sensitive in that region as they are feed accordingly to their relative sensitivity Also the dynamic "stress" of the major impulses in this region shouldn´t be that unlikely to provoke amps and woofers to show differences in their performance.

cheers,

Last edited by Juhleren; 21st February 2012 at 11:44 PM.
  Reply With Quote
Old 21st February 2012, 11:59 PM   #2527
back is offline back  Greece
diyAudio Member
 
Join Date: Nov 2005
Location: crete
could be because the amps are identical.

why not reproducing a low frequency and it`s harmonics with different amps

degrade the sound?
  Reply With Quote
Old 22nd February 2012, 12:52 AM   #2528
diyAudio Member
 
Join Date: Jan 2005
Location: Hawaii
I received my enclosure from HiFi2000 (ModuShop) and the quality is first rate.

I previously wired my UCD400 HG with H x R monoblocks for unbalanced operation only (pseudo balanced according to instructions). It sounds terrific.

I want to try the benefits of balanced wiring for the NCores, but I want to be able to compare both amps apples to apples. I understand how to wire the NCores for balanced, but how do I ALSO wire the NCores for unbalanced (pseudo balanced)?

Do I simply wire the RCAs off of the XLR female chassis connections using the standard pseudo balanced instructions?

Sorry for the novice questions, but as I said in an earlier post, I am not an engineer or anything close so don't yell at me for being stupid. Believe me, I will readily admit that I don't understand most of this stuff, but I can promise you that all of you would be just as lost in what I do !!!!
  Reply With Quote
Old 22nd February 2012, 06:09 AM   #2529
diyAudio Member
 
Join Date: Apr 2004
Location: BE/NL/RW/ZA
Clearly in the case of active speakers the question is about low-to-mid frequency distortion products arising from low-frequency signals. The thing that mainly amazes me is that it implies that at least the lower than -70dB distortion products of UcD are still audible at low frequencies (where the ear is much less sensitive and linear) through a woofer that is nowhere as linear. OTOH StigErik's woofer setup will have unusually low distortion and his room is well controlled.

Perhaps I'm just not being consistent enough. If I didn't accept that midband and HF distortion figures down to -90dB and better matter, I wouldn't be doing what I do. So all I might need to accept is that the same thing might very well hold true at low frequencies too.

@slowlearner: the only good way is using a dpdt switch between the RCA and XLR inputs.
__________________
There's a time for everything, and this is not it.

Last edited by Bruno Putzeys; 22nd February 2012 at 06:15 AM.
  Reply With Quote
Old 22nd February 2012, 07:02 AM   #2530
diyAudio Member
 
Join Date: Nov 2005
Location: Portland. Oregon
To answer my own question from a few days ago, the size of wire that will fit into each side of the speaker connector is AWG10, I tried AWG12 to see and no way will that fit (well maybe if you REALLY want to futz with it), but 10 fitted easily onto both sides of the connector for the bi-wiring arrangement.

Alan Garren

tomorrow I listen.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Hypex problem, who can help Hansms Class D 9 18th August 2013 06:49 AM
Hypex steveww Class D 14 18th November 2010 01:44 PM
Question for those who have tried hypex smps with hypex modules avian Class D 12 3rd March 2009 09:30 AM
Hypex UcD 180AD + signal wires, Power Supply ST, Hypex Transformer TR100A c10h12n2 Swap Meet 7 7th July 2007 03:55 PM
FS: Hypex UcD 400/180AD, hypex toroid Archmage Swap Meet 4 14th November 2006 04:23 AM


New To Site? Need Help?

All times are GMT. The time now is 01:50 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright ©1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2