Nait XS-2 damping factor

Indeed. Damping factor was not something I had heard for over 20 years. I had to go and look it up remind myself what it even was again. I think we all generally agree that it is very hard to match gear based on specs for expected sonic performance given that there are far too many variables and those variables are, well, highly variable during playback. They do help with the edge cases where extremes at ends of a given scale may prove problematic but otherwise I do not subscribe to it much.

However, I do have a huge amount of sympathy with the OP. I have posted before that demonstration facilities in Japan are nothing like we may be used to in the UK and often, attempting to match specs and then pray and hope it works when you get something home is about the most that can be hoped for. There just isn't much else to go on.

feeling_zen posted:

Indeed. Damping factor was not something I had heard for over 20 years. I had to go and look it up remind myself what it even was again.

I noticed the concept when Hi-fi World used it in the years that I read the magazine and found it useful in terms of amp and speaker matching. But if you buy all Naim you don't even need to know about this stuff because naim have done all the thinking for you. No thanks, I don't want to see this in Private Eye's OBN the week after next 

C.

feeling_zen posted:

Indeed. Damping factor was not something I had heard for over 20 years. I had to go and look it up remind myself what it even was again. I think we all generally agree that it is very hard to match gear based on specs for expected sonic performance given that there are far too many variables and those variables are, well, highly variable during playback. They do help with the edge cases where extremes at ends of a given scale may prove problematic but otherwise I do not subscribe to it much.

However, I do have a huge amount of sympathy with the OP. I have posted before that demonstration facilities in Japan are nothing like we may be used to in the UK and often, attempting to match specs and then pray and hope it works when you get something home is about the most that can be hoped for. There just isn't much else to go on.

I like the idea of highly variable variables. It reminds me of an interview with an eminent economist on the Today programme a few years after Britain decided not to go into the Euro. His view was that the advantage of a flexible exchange rate is that it's ...... flexible. 

I agree that it must be very difficult matching amplifiers and speakers when you cannot try them at home, or even to get a good in store demonstration at the very least. Here in the UK we have it very easy, and it seems strange that in such an advanced country with a big consumer industry such as Japan, that's it's so difficult. Clearly Naim's lack of presence in Japan  is driven by the lack of market, and the fact that equipment needs to be sent halfway round the world should it go wrong does make ownership more risky. In the OP's position I think I'd be going for a Japanese amplifier, of which there must be many excellent examples. At least then if anything goes wrong you can go to the local dealer. 

feeling_zen posted:

Indeed. Damping factor was not something I had heard for over 20 years. I had to go and look it up remind myself what it even was again. I think we all generally agree that it is very hard to match gear based on specs for expected sonic performance given that there are far too many variables and those variables are, well, highly variable during playback. They do help with the edge cases where extremes at ends of a given scale may prove problematic but otherwise I do not subscribe to it much.

However, I do have a huge amount of sympathy with the OP. I have posted before that demonstration facilities in Japan are nothing like we may be used to in the UK and often, attempting to match specs and then pray and hope it works when you get something home is about the most that can be hoped for. There just isn't much else to go on.

I very much agree that the issue here is the lack of proper demonstration facilities in Japan (F_Z, do you think this is due to a cultural difference?).

On the other hand, even when designing power amps, I'd pay comparatively little attention to the output impedance (the parameter that determines DF with an particular speaker), unless it looked 'odd'; instead other parameters are much more important:

1  Current rise rate
2  Uncompensated voltage slew rate (for some reason this needs to be at least 50% more than that which is theoretically required)
3  Stability Margin
4  Progressive ultrasonic filtration (particularly to prevent driver latch-up conditions [see 5] and TID in the presence of ultrasonic spuriae)
5  Effect of transient (near instantaneous) saturation current in all stages (this can cause horrible TID and THD in the presence of ultrasonic spuriae)
6  Capacitors
7  Power supply impedance (at all frequencies)
8  Output Impedance (i.e. control of DF)

In my experience, the capability to satisfactorily drive more 'awkward' speakers is controlled by 3, 1, 5, 7 & 8 in that order (but there may well be other factors that I've omitted/forgotten about!).

I couldn't begin to answer that Huge. I've been here for half my life but I think I would have to have been here in the 80's to have seen how the market was then to have a real comparison. Certainly, Japan is very detail orientated and that does show in the excellent quality and cost performance of a great many things whether it be food or consumer products. How much this comes into play with the selection methods for components is less clear. It would be fairly cost prohibitive for many dealers to operate the kind of low throughput big ticket item that account for many UK hifi shops. Further away from Tokyo you can get more one-on-one service (certainly my dealer back in Sapporo was not bad at all) but then the rents are lower too. But even then, the concept of a single speaker dem room would have been tossed out the window.

I wouldn't discourage anyone from buying Naim here. I'd just make sure that all the risks were known upfront. You have to really really want it. Certainly if I had to do it all over again, I'd still go for Naim. But ask me that again in 8 years when all my gear is up for recapping

I have plenty of Japanse hifi too for other systems and it sounds great - but even though it is made here I still couldn't get more than a noisy shop floor demo before dropping a few grand.

Thanks all.

Absolutely. I've already found that lightly damped amplifiers (Tube, sugden, Naim etc) matches highly damped speakers (ProAc, Spendor etc). However, here, In Japan, highly damped amplifiers(Luxman, Accuphase etc) are very much popular. On the other hand, the lightly damped amplifiers hardly exist in Japan excepting tube amps. Japanese audiophiles regard excellent amplifiers as highly damped amplifiers.

More strange to say, there are several Japanese dealers who are importing highly damped speakers from UK. They are demonstrating the highly damped speakers by using the highly damped amplifiers(Luxman, Accuphase) in Japanese Hi-End Show.

I think it's so crazy and Japanese Audio industries are already DEAD!

So I have to import lightly damped amplifiers individually from UK for my lovely ProAcs to get genuine good sounds.

Regards,

Kazu

That almost matches exacty what the ex Naim dealer told me 2 days ago when he was appraising my 282. He said that proper hifi was near dead. The only people really with any interest or money to spend on hifi will have all died in the next 20 years since they are all over 60 and when they go, that will be the final breath. The current generation has zero interest in anything but their iPod. Since home ownership is down, hifi means one thing; expensive headphones.

I think it was a bit of an exaggeration but not far off. The sad thing is, Some Japanese brands still make first rate gear. I might prefer Naim but there really is some good stuff made here but the market for it is mainly outside of Japan where it has more appreciation. Take high end AV components for example, I have a Denon DBT3313-UD AV streamer. Superb performance but all the built-in streaming services like Hulu and Netflix are disabled on the Japanese model dispite those services existing here. The unit is literally made a 5 minute drive away. I have this great AV streamer but need a crappy Amazon Fire box because even Japanese makers are not designing with the local market in mind anymore.

There are music lovers who want to spend on hifi like the OP, myself and a few others but we are a frustrated lot.

In general regarding damping factor' outside of the Naim fold. I wouldn't be so quick to dismiss its contribution to overall system significance.    I am absolutely sure in guessing that those who have listened to some of the other big ticket systems being demonstrated at hifi shows and come away unimpressed - are from using amps that have an unusually high damping factor of 1000 or more ( which seems popular at the moment) coupled with very highly inert and highly damped speakers ( think Magico . The polar opposite to Harbeth speakers) resulting in too much damping' robbing the bounce, vitality and life from music. Good for the demonstrators in dialling out flubby bass in less than ideal locations, not so good for showing the best of what's being presented.

A damping factor of 1000 with 8Ω speakers would require the speaker cables and voice coils to have less than 0.008Ω resistance!

(Just for reference my Spendor SP2s have 6.9Ω resistance in their voice coils).

Huge posted:

A damping factor of 1000 with 8Ω speakers would require the speaker cables and voice coils to have less than 0.008Ω resistance!

(Just for reference my Spendor SP2s have 6.9Ω resistance in their voice coils).

I'll let you do the maths, but Spendor speakers are usually recommended with low damping solid state unless there is a big lump of iron at the back end of valves or output transformerless designs.

TOBYJUG posted:

Huge posted:

A damping factor of 1000 with 8Ω speakers would require the speaker cables and voice coils to have less than 0.008Ω resistance!

(Just for reference my Spendor SP2s have 6.9Ω resistance in their voice coils).

I'll let you do the maths, but Spendor speakers are usually recommended with low damping solid state unless there is a big lump of iron at the back end of valves or output transformerless designs.

Sorry, I completely fail to see the relevance of that to the effective impossibility of achieving a damping factor of 1000.
Even just the contact resistance of the 4mm plugs (or binding posts) at the back of the amp and speakers makes it impossible.

True. Could possibly account to the idea that some systems are not so dependent on critical cable matching and do their thing regardless.

Yes indeed, that's a good observation.

Huge posted:

A damping factor of 1000 with 8Ω speakers would require the speaker cables and voice coils to have less than 0.008Ω resistance!

(Just for reference my Spendor SP2s have 6.9Ω resistance in their voice coils).

Coreection, the amplifier has to have an output impedance of <0.008Ω.

i haven't come across any that with that high DF at 8Ω speaker impedance, but declared DF of up to about 200 into 8Ω is not uncommon.

Kazu, As speakers go, how damped are your proposed ProAcs?

C.

I had some high DF amplifiers once to drive my subs. Just for fun, I sometimes used them to drive my little ProAcs and the one with a DF of ­1000 (Crown CE4000) did sound much better than a fanless Crown K2 which has a DF of over 3000!  I think the result would have been the same with any overdamped or underdamped speakers. Some amplifiers just sound better than others.

Christopher_M posted:

Kazu, As speakers go, how damped are your proposed ProAcs?

C.

My own ProAcs are the Response DB1s and the Tablette anniversary.

Both my ProAcs are driven with the Sugden A21(DF around 17). That's good sounds!

Regarding the DB1s, ProAc (Mr.Stewart) heartily recommended they should be driven with the Naim XS rather than the Sugden A21.

Kazu 

Kazuhito posted:

My own ProAcs are the Response DB1s and the Tablette anniversary.

Both my ProAcs are driven with the Sugden A21(DF around 17). That's good sounds!

Regarding the DB1s, ProAc (Mr.Stewart) heartily recommended they should be driven with the Naim XS rather than the Sugden A21.

The Sugden A21 is very highly respected so I'm not surprised the ProAcs sound good. From the magazine article that I referred to earlier: "The rival A21 S2 is a tad more insightful and transparent [than the Nait XS] across the mid and treble, if less obviously powerful and propulsive".

What are your sources?

C.

Because I know Richard doesn't like parallel discussions happening in the background, I'll share the latest developments with respects to finding a dealer for the OP.  I contacted my dealer to ask whether they were open to selling additional Naim products to others in Japan. They decided, fairly enough, that it is too risky. I relayed something similar to the following to the OP and offered my own take (not the dealer's) on the scenario as a whole:

The dealer has a concern about selling such items to unknown customers in Japan and has decided not to.

I can understand their position on this. After all, each dealer has a responsibility for after service to their customers. So if they don't think they can provide this then they may have a policy not to sell. Not just Naim, but various manufacturers are extremely strict about the service level provided to end customers by their contracted dealers. If they feel that the service level provided is not sufficient then it can cause trouble between the manufacturer and the dealer. In this case, a UK dealer would not even be able to do a basic functional check of a 115v unit before shipping it. There is nothing in the dealer contract that prohibits providing a 115v unit but each dealer must make a decision based on the possible impact on the dealer/customer/manufacturer relationship.

I don't think any of this is a bad thing. My dealer is just one of many and you are free to contact others. If you have your heart set on a Naim amp then I don't think there is any chance that you will not be able to get hold of one. You can look up dealers gloablly on the Naim website using the "Find a Retailer" tool. I did a quick search last night for dealers on the West coast of Canada and the US (Vancouver, San Fran, Los Angeles) and there are a few that carry the XS range. If any of them are willing to sell to customers in Japan, as 115v countries, they would also be in a position to at least perform a functional test for you before shipping the unit.

You may have to contact a number of dealers but I am sure you will find one.

Innocent Bystander posted:

Huge posted:

A damping factor of 1000 with 8Ω speakers would require the speaker cables and voice coils to have less than 0.008Ω resistance!

(Just for reference my Spendor SP2s have 6.9Ω resistance in their voice coils).

Coreection, the amplifier has to have an output impedance of <0.008Ω.

i haven't come across any that with that high DF at 8Ω speaker impedance, but declared DF of up to about 200 into 8Ω is not uncommon.

IB, the equivalent resistance of the amp's output impedance, the resistances of the speaker cables, the contact resistance of their terminations and the resistance of the voice coils are all in series.

To determine the true damping factor, the impedance of the speaker at the specified frequency has to be divided by the sum of all these resistances.

Huge posted:

Innocent Bystander posted:

Huge posted:

A damping factor of 1000 with 8Ω speakers would require the speaker cables and voice coils to have less than 0.008Ω resistance!

(Just for reference my Spendor SP2s have 6.9Ω resistance in their voice coils).

Coreection, the amplifier has to have an output impedance of <0.008Ω.

i haven't come across any that with that high DF at 8Ω speaker impedance, but declared DF of up to about 200 into 8Ω is not uncommon.

IB, the equivalent resistance of the amp's output impedance, the resistances of the speaker cables, the contact resistance of their terminations and the resistance of the voice coils are all in series.

To determine the true damping factor, the impedance of the speaker at the specified frequency has to be divided by the sum of all these resistances.

Hi Huge, I think we're talking at cross purposes here as I fully agree with you, just the terms of your post appeared to be reversed. For others reading this, taking the cables as having negligible effect, DF is speaker  impedance (e.g nominally 8Ω) divided by power amp output impedance. The speaker cable impedance (and contact resistance of the plugs) needs to be added  to one or the other, depending on what is being considered. 

For a speaker with nominally 8Ω impedance, and cables/connectors with negligible impedance the amp would have to have an output impedance of 0.008Ω for DF of 1000, but your post suggested it is the the speakers that would have to have an impedance of 0.008Ω, which is patently impossible in practice if a speaker has an impedance anywhere more than 1/1000th of the nominal 8Ω.

Innocent Bystander posted:

Huge posted:

Innocent Bystander posted:

Huge posted:

A damping factor of 1000 with 8Ω speakers would require the speaker cables and voice coils to have less than 0.008Ω resistance!

(Just for reference my Spendor SP2s have 6.9Ω resistance in their voice coils).

Coreection, the amplifier has to have an output impedance of <0.008Ω.

i haven't come across any that with that high DF at 8Ω speaker impedance, but declared DF of up to about 200 into 8Ω is not uncommon.

IB, the equivalent resistance of the amp's output impedance, the resistances of the speaker cables, the contact resistance of their terminations and the resistance of the voice coils are all in series.

To determine the true damping factor, the impedance of the speaker at the specified frequency has to be divided by the sum of all these resistances.

Hi Huge, I think we're talking at cross purposes here as I fully agree with you, just the terms of your post appeared to be reversed. For others reading this, taking the cables as having negligible effect, DF is speaker  impedance (e.g nominally 8Ω) divided by power amp output impedance. The speaker cable impedance (and contact resistance of the plugs) needs to be added  to one or the other, depending on what is being considered. 

For a speaker with nominally 8Ω impedance, and cables/connectors with negligible impedance the amp would have to have an output impedance of 0.008Ω for DF of 1000, but your post suggested it is the the speakers that would have to have an impedance of 0.008Ω, which is patently impossible in practice if a speaker has an impedance anywhere more than 1/1000th of the nominal 8Ω.

If you are talking about damping factor for a given amp and speaker, then you are considering the damping of the speaker cone.  To establish this you have to consider the amplifier output, the speaker connections and the speaker as a circuit.  In this case the DF is the speaker impedance divided by the circuit resistance (not just the amp).

If you are talking about just the amp, then there can't be damping factor as there's nothing to damp!

I still think we're talking at cross purposes not disagreeing. 'DF' of an amp is into a nominal impedance speaker load (typically 8Ω) which includes the cables etc, and at a specified frequency usually around 40-50 Hz.  DF is just a term, meaning, in this context, the speaker impedance divided by the amp output impedance, and yes, the cables and connection impedance needs to be included, if talking about the amp DF  thay would be added to the speaker actual minimum impedance.

IB, the problem is that to use DF in reference to the amp alone is meaningless as there's nothing to damp.  When looking at an amp and speakers this same measurement gives a incorrect perception of the damping of the system.

Take for instance my speakers
They are 8Ω nominal impedance, and the bass/mid driver has a resistance of 6.9Ω
(N.B. their minimal impedance is 6.7Ω. but below 2.5kHz, the minimum impedance is about 7.4Ω)

So taking an amp with a high output impedance of 0.4Ω, adding 4x4mm connectors = 20mΩ total, 2 speaker wires (12AWG, 5M) = 0.05Ω and adding 6.9Ω, gives an electrical damping factor of 8 / (0.4 + 0.02 + 0.05 + 6.9) = 1.085.

So taking an amp with a low output impedance of 0.004Ω, adding 4x4mm connectors = 20mΩ total, 2 speaker wires (12AWG, 5M) = 0.05Ω and adding 6.9Ω, gives an electrical damping factor of 8 / (0.004 + 0.02 + 0.05 + 6.9) = 1.147.

So reducing the amp output impedance by a factor of 100 has increased the DF by about 6%!

This is why the figure the marketing people quote as the "Amplifier Damping Factor" is largely irrelevant, and actually misleading.

Hi Kazu,

You seem wedded to your ProAcs but imo it would also be interesting to hear your Sugden into some 90dB efficient  loudspeakers too.

Chris