Bloody Switch Mode PS....I Think!!!

Posted by: Geoff P on 26 December 2004

OK

I believe I have finally to admit the achilles heel of the DVD players competing with Naim is the Switch Mode PS's inside em.
Very popular, cheap to make, only need small transformers and coils etc BUT......OH DEAR the R/F.

I have suffered from this twice now and have just managed to prove it a 3rd time. My plasma is displaying noise dots in strips across the black background carried in on the component signal cables.

I switch between two component sources since the advent of a DVD-R to replace my knackered VCR, so I can do tests and I have satisfied myself the noise comes in this way. When neither source is "switched in" by the A/V receiever they pass through, but the boxes are powered and their cables are still connected, voila no noise! So it ain't getting to the plasma by aerial pickup
Switch one in you get a noise pattern. Switch the other one in instead, you get a different noise pattern.Putting R/F collars on leads any where makes no difference

Interestingly it is only visible against black as dark blue noise, as soon as a visual image with detail is displayed even right up close it is immpossible to see it. BUT it's there, right?

So Naim's insistance on old fashioned power supplies sounds very right.

Warning don't look to close. You may have the problem aswell....however any sympathetic experineces, suggestions etc are welcome here.

regards
GEOFF

"Just trying to make a NAIM for myself"
Posted on: 29 December 2004 by Frank Abela
Geoff

Ask your friendly local dealer to lend you a Chord Co Clearway to try on the screen. This may solve the problem. If it doesn't, try it on one of the sources that's giving you the trouble and see if it fixes the problem there instead.

Of course, if it's a £50 DVD-R machine, it seems a touch silly to be applying a £240 noise suppressor in the form of the Clearway, but what choice do you have???

Regards,
Frank.
All opinions are my own and do not reflect the opinion of any organisations I work for, except where this is stated explicitly.
Posted on: 29 December 2004 by Geoff P
Frank

Thanks for the info. I will see if I can get a "ëuro" version for over here.

Someone else said it might be a sync. problem between the component progressive signal coming from the sources and the Plasma's input board ( the plasma is about 2 1/2 years old Pannasonic).

regards
GEOFF

"Just trying to make a NAIM for myself"
Posted on: 01 February 2005 by Tigger24
Regarding the clearway mains enhancer by chord, you can get very similar devices from the likes of rs components for about £40 that are designed to be an inline filterand will probably be about the same size as the clearway and fiited with a short iec flylead on one end and an iec socket on the other. Hope this helps.
best wishes dean
Posted on: 01 February 2005 by Neill Ferguson
Geoff

This message will be edited change the mains cable, it will have the biggest effect. I know were not supposed to talk about them but they do work and they make a difference.

Neill
Posted on: 01 February 2005 by Geoff P
Guys

Thanks for your helpfull input. I posted this on another thread yesterday and it is appropriate here aswell.

"On the red & white flecks are they running in stripes across the background of the picture?

I had this effect on my plasma and discoverd by accident that it was pickup of interference thru' the mains and/or video signal cable simply from the way they were hanging in relation to radiated fields from god knows where exactly, just when I had almost decided I had a fault in my DVD player . I wiggled and gently moved these two leads around and found a different position for them which got rid of the noise flecks on the picture. I managed to get them propped in that position and have had no trouble since. Incidentally using the ferrite cores clamped around the leads did NOT work. Strange, but worth a try"

So there you go. My topic starter on this thread turns out to be unfair. God this hobby is a nightmare at times.

regards
GEOFF
Posted on: 02 February 2005 by Tigger24
one thing that may be worth doing before getting any kind of device like a clearway, would be to get hold of a noise sniffer, which basically plugs into a wall socket and amplifies any mains noise within the system. If however you do choose to change you're amins cable, remember that you will probably not be able to fit a wattgate or other large bodied iec into the socket on the plasma, unbless it is mounted on the back panel and faces outwards. There is a dutch based company called kempelektroniks who specialise in mains cables and mains devices. There website is: www.kempelektroniks.com and they should be able to loan you a noise sniffer. If you choose to go for a new cable then i would certainly look into the kemp stuff as theirs is 4core cable which includes an earth drain and is very well put together and is about the same price as the isotek range. I would also check you're video cables for any breaks or kinks in the cable.
Posted on: 13 February 2005 by Nime
Interesting.

I turned everything off last nght after watching a DVD film but forgot to switch off the subwoofer.

My wife was watching terrestrial TV later and I noticed a series of thin diagional lines of dots on the screen. Hardly noticable but there.
I mumbled something about our neighbour probably using a drill in his house repairs. But my wife noticed the diode on the sub. Switching off the sub removed them immediately. It runs a hybrid A/B/D power amp.

I've never noticed this before. Nor the least problem on sound quality with it in use. It always adds to the sound quality on stereo music on high level connections. I've tried many times turning it on and off when listening to judge its effect.

The CRT TV is usually fed by a scart cable from the kit in the rack. On terrestrial TV it is still connected of course, even when not in use.

Nime
Posted on: 13 February 2005 by Geoff P
Nime

Like I said "...this hobby is a nightmare at times". Now you ahve me switching sub woofers on and off.

Eek
Posted on: 13 February 2005 by Nime
quote:
Originally posted by Geoff P:
Nime

Like I said "...this hobby is a nightmare at times". Now you ahve me switching sub woofers on and off.

Eek


Ah, but Grasshopper. You admitted to turning your sub on-and-off in the past. (if I remember correctly) Isn't your sub one of those with an old-fashioned analogue amp anyway? Winker

There is no indication that my sub is spoiling the music in my system. Endlessly repeated on-or-off testing always produces a slight lift in sound quality. On any source and with any type of music.

But I am not using hair-shirt, paint-stripper speakers any more. Or a "high-end" source. So there may be members out there who claim such hybrid power amps do affect sound quality.

My subwoofer simply offers an advantage which I value well beyond any theoretical downside on sound quality. It took me over thirty years to finally get real bass and I'm not giving it up now! They'll have to pry my sub from my dying fingers. Big Grin

Nime
Posted on: 14 February 2005 by Frank Abela
Nime

I didn't realize SVS subs were imported into the UK. Or is that a grey import? And how much was it?
Posted on: 14 February 2005 by gusi
Geoff,

TV gear is quite sensitive to earth loops as well. You often get horizontal or diagonal stripes if your kit isn't earthed correctly.

cheers
Gus
Posted on: 15 February 2005 by Nime
quote:
Originally posted by Frank Abela:
Nime

I didn't realize SVS subs were imported into the UK. Or is that a grey import? And how much was it?


They are only available for purchase online. Even in the USA as far as I know. They use Bax for their worldwide distribution.

If you are in the UK or Europe you can take advantage of the low dollar value against the pound & Euro. It makes their subs extremely competitive in price v performance. Downside is the size of their enclosures and lack of demo facilities unless you can find someone local via an AV forum and link up for a listen.

I can't give specific prices in other currencies. Prices are always in dollars which you pay in adfvance with a credit card. Your card is only debitted when the sub is despatched.

You pay for Bax in advance to deliver and then when the sub arrives you pay the driver import tax of about 4% + local VAT on top of the sub price + the air freight charges. So around 22% extra in the UK.

If you go to their website and place an unconfirmed order for a specific subwoofer then enter your home country you will get a fixed price for delivery. Most customers choose door to door rather than local airport.

Their products are aimed squarely at the AV market but much enjoyed by stereo fans as well. All but the smallest PB10-ISD (and their non-active subs) offer high and low level connections, roll-off filters, crossovers etc.
They all use large enclosures and 12" drivers (and large ports) to achieve very high SPLs with low distortion.

This is popular US-based international AV/HT forum with countless happy SVS customers. The directors of SVS post there regularly.

http://www.hometheaterforum.com/

This is the SVS website. Ther service is second to none. Just e-mail them and they will recommend a model based on your stated desires: Room size/music/AV/HT/ usual listening levels. They have a huge library of data. The directors regularly recommned alternative manufacturers products where considered appropriate. Their e-mail sevice is legendary. Some customers exchange e-mails for months before making a final decision.

http://www.svsubwoofers.com/

Sorry for the long monologue. But this is the sort of info asked for again and again by poster after poster on the AV fora when they first hear about SV Subwoofers. It just saves time if you hear all the ins-and-outs in one go.

Favorite subs are the Ultra models for those who can afford them. They have a superior driver, more powerful amplifier and greater dynamic range with lower distortion than the Plus and PCI range.

240 Volt models are supplied as standard to European destinations. It doesn't hurt to specify 240 Volts anyway.

Independant reviews are listed on the SVS website.

I hope this doesn't embarrass Naim's forum policies. It certainly wasn't my intention.
It just gets so boring reading (and writing) exactly the same infomation so many times on the AV fora.

Nime
Posted on: 16 February 2005 by Frank Abela
Thanks for the info Nime.

Regards,
Frank.
Posted on: 17 February 2005 by Geoff P
quote:
TV gear is quite sensitive to earth loops as well. You often get horizontal or diagonal stripes if your kit isn't earthed correctly.
cheers
Gus


Gus
Thanks for the comment. As I mentioned with my Plasma it seemed the noise was being picked up due to cable location. I have not had to play with earthing and have not seen the problem since moving the cables so all is well at present.

regards
GEOFF