[Occam]

Steven,

"....and got mixed opinions...."

Thank goodness technology isn't democratic. Folks don't get to vote on whether something will work, or not. It does, or it doesn't. Actually, when I first encountered the problem of buzzing toroids a few years ago, my reaction was. like one of the posters, ' those capacitors will blow"..
I personally don't use a humbuster because I don't have that specific problem in my house, but I did build one for a friend's Creek 5530. Worked like a charm and nothing blew.
Jens has iimplemented this solution numerous times and that it does what it is supposed to do. (its not going to help when the problem when it isn't DC on the line, but rather a loose bolt). What more could one ask for?

Indeed,  the 3 or 4 differing schematics referenced appear to be different, but they are topologically equivalent.

[kyrill]

As I don't have buzzing toroids (one buzzes a second when turning on, the other is always "sleeping") may I assume that the net power has no dc at a relevant level?

[Occam]

Kyrill,

Yup.  We should consider ourselves lucky, no AC/DC problems. Now, if I could just work on my people skills....

[AKSA]

Occam,

Riotous reply!!  Truly befitting black NYC humor!!  ROTFLMAO!!        

Cheers,

Hugh

[peranders]

The Swedish site offers the printed PCB for 150 Kronas ($20 US dollars) but one supplies the caps and diodes and connectors; probably wouldn't be cost-effective compared to the LC Audio filter ($43?) but it might make an interesting project (with the PCB lending some reassurance that one was doing things correctly?)

This filter can be done very easily. Lars Clausen has only one cap plus a tranzil. This is probably also OK but I have small doubts about the first suggestion because the caps aren't protect at all for high voltage (current) transients. But my and Lars' design have effective clamping achieved by the diodes/tranzil.

My design is maybe a bit overkill but I sleep good at nights because it can take more 6 A continuiosly and and 60-100 A peak without any restrictions

[Tonto Yoder]

My design is maybe a bit overkill but I sleep good at nights because it can take more 6 A continuiosly and and 60-100 A peak without any restrictions

Thanks for the clarification. I probably shouldn't have used the term "cost-effective" in comparing the two.  It's common for audiophiles to think of DIY as cheaper than an assembled product, but it's certainly possible that your board could be a great value if it performs its function well.

[peranders]

Thanks for the clarification. I probably shouldn't have used the term "cost-effective" in comparing the two.

"cost-effective" what is that really? Sometimes it must cost nothing, sometimes it costs huge amounts of money! I think you can't use this expression at all in DIY.

[WerTicus]

Hey guys after reading this thread I started to look into the concept of a DC blocker some more.....

I just finished building this:

http://diyparadise.com/dablok.html

As it turns out my torriods were humming along.... though being in a very heavy case I had not noticed before I read this article and really looked into it!

However I have always been annoyed by the sound comming from the tweeters when the amp was on.

The schematic above worked a treat and the noise floor of the tweeters has dropped considerably.

Where as before on a bad day you could 'just' hear the tweeters from listening position.

Now to hear anything during silence you have to be VERY close to them... which is awesome!  I am yet to do an extensive listen to see about negative effects on dynamics or anything like that.

I built the blocker into a power cable so I can move it around easily and try it all over the place its well insulated of course and I wont be touching it in operation.  I assume 3x layers of electrical tape should enough on each wire?

but ill report back when i do!  which wont be for a couple days.

[SamL]

A novice question.
Will this "DC blocker" a worth while improvement to switch mode power supply? Like those used by CD/DVD player?

[Occam]

A novice question.
Will this "DC blocker" a worth while improvement to switch mode power supply? Like those used by CD/DVD player?

I wouldn't think so. The AC is generally rectifired (on a CD/DVD player) prior to the dc being switched and passed to a ferrite transformer. In other words, AC with a DC component never hits the transformer.

[WerTicus]

which means it also wouldnt be any use on a computer i suppose.

[peranders]

This DC filter is ONLY for humming toroids, nothing else. The DC does no harm it only produces audible hum.

[WerTicus]

yup and my torriod hums no more

[Tonto Yoder]

"cost-effective" what is that really? Sometimes it must cost nothing, sometimes it costs huge amounts of money! I think you can't use this expression at all in DIY.

I respectfully disagree. I think the concept of cost-effectiveness is very valid in DIY:  if an assembled speaker is available for $200 and the same identical speaker is available as a kit for $150, it may not be cost-effective to go DIY, saving only $50 but spending 5 hours to assemble the kit.

My initial mistake was comparing your DC blocker (PCB, parts and shipping) with the LC Audio blocker ONLY in terms of price & time involved; since you've clarified that the two finished products are far from identical, I see my mistake now.

[JohnR]

I think the concept of cost-effectiveness is very valid in DIY:  if an assembled speaker is available for $200 and the same identical speaker is available as a kit for $150, it may not be cost-effective to go DIY, saving only $50 but spending 5 hours to assemble the kit.

In which case the DIYer will turn his nose up at it, and either spend $500 on something which will blow everything on the planet away, or $15 building an array of 69c-special drivers which is going to blow away those crummy $200 speakers anyway.

Trust me, I'm a doctor.. or is that patient?

[Tonto Yoder]

I think the concept of cost-effectiveness is very valid in DIY:  if an assembled speaker is available for $200 and the same identical speaker is available as a kit for $150, it may not be cost-effective to go DIY, saving only $50 but spending 5 hours to assemble the kit.

In which case the DIYer will turn his nose up at it, and either spend $500 on something which will blow everything on the planet away, or $15 building an array of 69c-special drivers which is going to blow aw ...

Doesn't really contradict what I was trying to say, but just approaches the cost-effectiveness question from a DIY point of view.  If my hypothetical $200 speakers were sold for $100 as a kit, it would seem wise to go the kit route,  "paying" yourself for the assembly time.  I still think the CONCEPT of cost-effectiveness is valid.

[WerTicus]

i am amazed that anyone would even question the cost effectivness of DIY.

its OBVIOUSLY good value!   I have heard 150 kits which floor 600$ speakers

and i have hear 8k kits which floor anything you got


the thing about DIY is you are having FUN building whatever... its part of the hobbie if you add your time to the COST then your missing the point totally!

[Tonto Yoder]

The thing about DIY is you are having FUN building whatever... it's part of the hobby: if you add your time to the COST, then you're missing the point totally!

The enjoyment factor is hard to calculate but certainly there for some people. For others, it MAY just be a matter of saving money by DIY.

[JohnR]

A lot of people would probably PAY to have the benefits of DIY. A sense of achievement, increased confidence, credibility with your supposed engineer work colleagues (who haven't done anything but touch a computer keyboard in ten years), kudos with your DIY-challenged mates, hey the list goes on!

Pity it doesn't have much effect on the chicks though  




PS. Did I mention that DIY makes your teeth whiter?


PPS...... what was this thread about?  

[WerTicus]

i think this thread was about a dc blocking circuit

and then about how awesome diy is and how it makes your teeth whiter and gets you laid... ALL THE TIME