assessing tweaks...
Posted by: ken c on 29 April 2001
again, not sure this is worth a thread, but here goes...
you will recall i mentioned in one of active system reports that my system has become much more revealing. of course, this is a double edged sword.
however, i also mentioned that the system is teaching me quite a few things too. for example, i can now tell the slight variability of performance over time. i emphasize "slight" as the effect is small and doesnt really have a big impact on the flow of music. but its still audible for example, you may get thinner voices for a while, but this soon corrects itself. i suspect this is probably mains quality related - i dunno -- i have a mains spur based on 6mm sq twin and earth cable. power is fed to the black boxes via a grahams hydra arrangement.
what i have learnt is that given that my system performance has this tiny variability (for the sake of argument, lets just use a somewhat meaningless percentage to qualify this variability, like plus or minus 5percent). so i call the 10 percent band, the "random effects" band.
in future, when i do any system changes, i will need to make sure that any improvement, or otherwise, is big enough to be significantly OUTSIDE this random effects band. i am not suggesting that this is some new universal wisdom -- i am just sharing some thoughts on changes that my new system are forcing on me... and in any case the validity or otherwise of what i am saying probably depends on what system you have...
the interesting point of course if how to reduce this variability band to near zero percent -- but i sense an impossibility here.
enjoy...
ken
The only changes that interest me now are ones that give me more information of the disc (i.e a source improvement) or a change that gives me more scale and presence (speaker change).
My feeling is that all the other changes we seem to talk about (stands/cables) offer limited improvement and certainly don't change the fundamental character of a system.
regards
Dev
How to erase those 10%
Step 1:
Dig a basement in case your house has none
Step 2:
Install a Diesel/Gasoil Generator in a 100% soundproof room
as it produces 380V - three phase - DC you will need a converter to 230/240 V AC
Step 3:
Plug in your system
Step 4:
Enjoy
Haven't seen it with my own eyes, but there is a dealer near Duesseldorf in Germany who has this at home.
When a film equipment rental house goes broke, you can usually get a generator for a good price.
Testing it:
No problem, a generator is for rent at about
50 - 70 GBP (5kw Honda super silence crystal frequency controlled - to get real 50 Hz) a day,
Bigger ones for more money
90 kw - around 250 - 350 GBP/day
This would be, to my opinion, the final mains upgrade.
(A sure place in the "Flat Earth Hall of Fame" guaranteed)
Think about it
Guido
:
Photovoltaic panels - the problem is the inverter. PV panels are current sources, need to be arranged in large series-parallel arrays to get much useful power - which is then fed through an inverter to get AC. Inverters do not produce anything as nice as a sine wave, even the ones that claim they do!
The result could be rather like powering your entire system off a Lingo.
You could perhaps regulate the DC feed directly as a substitute for a *cap, but the source impedance for most domestic arrays is too high - the result will not get close even to a NAPSC. PV panels are expensive (about £10 per gross watt), output is weather and location dependant output. Limited evening listening!
AC generators: drawbacks that come to mind are matters of regulation - voltage and frequency. Frequency is only a real issue if you're going to
run a turntable with a synchronous motor. More serious is the voltage regulation; generators can have significant internal impedance (resistance), the upshot being that voltage and frequency tend to wander. It only ceases to be an issue in the larger sizes...we're not talking yer 3Hp Hondas here.
The generator will need to be loaded down to get the alternator regulating properly - somewhere around 25% or more of rated output I'd guess - and even then, the regulation will not be significantly better (or even as good as)the mains. Nice and wasteful, that.
But the real killer could be spikes. Alternators generally regulate the field coil current to vary output - and stepwise tap changing here can lead to some truly enormous (if mometary ) voltage spikes on the output; 12v car electronics have to deal frequently with -80v spikes from the alternator for example. On the National Grid it is less of an issue - all those transformers provide low pass filtering for free - but think about it before you plug in the CDS2...
Mr. Fusion anyone ?
Martin
[This message was edited by Martin Clark on MONDAY 30 April 2001 at 15:51.]
Nice post. Even without an active system, I guess my random effects band is about 10% most of the time. Occasionally it might drift down to about 20%ish [but that could include 'mood swings']
My recollection is that changes to my system in the early days eg 32.5 to 72 or (say) nirvanah to valhalla, were A LOT LESS THAN 10% and I sometimes wonder whether the improvement was entirely due to, or heavily influenced by, external effects that generate this random effects band.
On the other hand, the change from Sound Org to Audio Tech table was A LOT MORE THAN 10%; as, IMHO, is the effect of putting the LP12 drive belt back on 'upside down' (for example).
No doubt about it IMO, you need to be aware of the random effects band and try to make sure it isn't masking/enhancing system changes.
This, I think, is where a good dealer and reliable manufacturer come in handy
Cheers
Don
quote:
No doubt about it IMO, you need to be aware of the random effects band and try to make sure it isn't masking/enhancing system changes.This, I think, is where a good dealer and reliable manufacturer come in handy
thankfully, in naim audio, we have a manufacturer of highly reliable audio systems (or, to be loyal to the new "brand", should i now say "manufacturer of world class hifi" ??)
but unfortunately, this high reliability of maim equipment is a double edged sword. it tempts short cuts (i.e. there is no reason why it wont work). and unless you know the "naim" sound, you can be fooled into thinking that you just lash up the system together and provided you use the right cabes and the system makes some sort of sound, then thats enough. wrong, wrong, wrong !!!!
i am afraid i DONT KNOW ANY DEALER who would have the inclination/time/(competence??) to take hifi systems installation a step further and assess whether the installed system sounds the way it should, i.e. make music. this is compounded by the fact that quite a lot of them dont have naim systems at home, so they really dont know what a good and properly installed naim system sounds like. they dont know the "naim" sound. too bad...
perhaps i am being unrealistic in my expectations after all they do have margins to worry about and this sort of service would be too time consuming/expensive to provide. but if the only "service" that the dealer provides is to come to my home and connect black box A to another black box B using cable C (or is it D, or E??) then i cannot hold out too much hope for the future of this somewhat specialist industry. if these guys do not provide value, then eventually, e-tailers will drive their business extinct. (might do anyway, regardless...)
i know i exaggerate a little... but i strongly believe naim "customers" value good music at home, and if this objective is somehow lost, then we are all lost too...
phew, got that off my chest!!! now, where we we???
enjoy...
ken
just spent 20 minutes typing [my typing is very slow] response only to find i had been unexpectedly logged out. Somehow I then 'lost' my typed response so will have to try again tomorrow when I have a bit more time again.
Now back to the Pirates of Penz.. whats it's name ? [oh! the guist of the message was Grahams are a good dealer]
Cheers
Don
quote:
oh! the guist of the message was Grahams are a good dealer
almost all my naim kit is from grahams.
whether a particular dealer is "good" for you or not depends on what YOU look for in one.
look fwd to reading your lost posting...
enjoy...
ken
If you know what I'm on about , ever think about using that experience as a "yardstick" to judge or measure a system's performance (as opposed to PRAT, imaging , bass , treble or anything else involving the "thought process") ?
regards,
dave
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oh! the guist of the message was Grahams are a good dealer
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[Hope I don't loose this post - but noticed a thread elsewhere that suggests this is a common problem!]
I agree with what you say about dealers in general, but there are IMHO a small number who really do help.
I have used Grahams for about 6 years. They have taken me through [new and second hand] LP12 resets; Ekos rebuild, Lingo, Linto,CDS1, 72 to 82, supercap, 52, 135s [bought these privately 2nd hand] Base rack, handfull of cables, LPs and CDs. Also demo'd N802s, CDS2 and 500 but bought Wilsons and am hanging on about the 500 and CDS2.
I have always felt that Grahams had fully evaluated each piece of equipment and could demonstrate, even in their shop, its strengths and weaknesses [concentrating on the strengths! but not always Naim either].
This meant that I could judge more easily,how big the change was and whether it was worthwhile, even if it was less than the 'random effects band'. I have felt confident that each upgrade would push the system enjoyment upwards, and take the REB along with it.
Most times [and always, if I asked], Grahams have delivered and installed the kit. They have listened to the old system first and suggested and made 'tweaks'. They have set up the new kit so that it sounds 'right' to them without demanding whether I think its right [always difficult when suffering 'buyer's remorse] and assured me it will improve over the next couple of MONTHS. They always reassure that they will sort it out or take it back, if after the run-in it dosen't please. But they've never needed to come back!
Perhaps i've just been lucky. But given that I live 70 miles from their shop I reckon they've done really well. However, their real skill IMO is evaluating the kit, demonstating it honestly and assessing my preferences somehow.
I have listened to other kit elswhere, where a change of interconnect at £2,000 made a < than REB change and I was expexted to shreik with delight and cough up > £60K on the spot - no home dem in sight.
I now add the obligatory disclaimer to working for/living with/having any financial interest in Grahams other than hoping that if they read some of these posts, they will remember next time i'm in looking at that ex-dem 500 [they don't know its ex-dem yet of course ]
Cheers
Don
enjoy...
ken
Paul at Billy Vee (my local) is a real Naim enthusiast and they don't charge extra for servicing (don't know if Grahams do or not).
my fault for introducing this "dealer" topic into this thread... no matter...
enjoy...
ken
what the hell is a "tweak" anyway???
(a) a small (rational) change to hifi system configuration, involving existing components components (no new stuff)-- that results in (significant?) changes (improvements?) to the system musical performance. examples?
(b) same as (a) but may involve new components (in which case, whats an upgrade??). trying different interconnects -- is that tweaking? different stands? naim speaker plugs vs airlocks??
(c) same as (a), but change is no necessarily rationally based, but MAY make significant positive changes though... example, ehhh, cant think of any -- except perhaps din plug centering -- but i think this has a rational basis...
anyway, any thoughts -- when we have agreed a definition -- i suggest we stick to it...
enjoy...
ken
good question, IMHO your version (a) without (alternatives) is pretty close ie
'a small change to hifi system configuration, involving existing components that results in changes to the system musical performance'.
I'm not sure about the 'small' change to configuration, this might preclude turning the system through 90 deg for example. I think the cost shouldn't be too much but I don't know what 'too much' actually is, and although new 'components' should be excluded, I would allow cables, cones, spikes, stands, dedicated spurs, direct earthing -come to think of it, just about anything that doesn't come in the box from Salisbury. This even includes modifying the internal wiring inside a 52 by your 'authorised dealer' (oops sorry, was trying not to mention dealers again !)
As for 'significant' change, well this goes back to your initial post - if its more than your Random Effects Band, BINGO, no problem you're delighted - if its less than the REB and IRREVERSIBLE - OH DEAR, it could be months before you realised you'd conned yourself. This is where a good dealer comes in handy (oops sorry again !)
Cheers
Don
quote:
This is where a good dealer comes in handy (oops sorry again !)
ha ha ha ha ha, very funny... you know something i do/dont???
enjoy...
ken
Not that i'm aware of, i'm not a SECRET DEALER.
What I had in mind was things like 'Parastatic ?' record cleaning spray with the little 'p' stickers so you knew which records you'd cleaned and 'Pixell' record cleaning rollers - do you remember ? [Pixell looked like draughting tape, wound sticky side out, on a chrome roller that was meant to pick up dirt from records].
And the Parastatic cleaner seemed to leave a sticky residue on the record surface which captured dust like fly-paper traps flies. I've never been able to get the dam stuff off, completely ireversible [tweak ?] and I don't need the little 'p' stickers to remind me which records I ruined
IFFFF i'd spoken to a proper dealer BEFORE trying, I might have saved a lot of damaged records
Cheers
Don