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novosibir
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Post by novosibir » Tue May 23, 2006 9:56 am

The point is, that I haven't seen yet a PCB designed so properly, that it could be comparable to a PTP turret or eyelet board soundwise and in regard to the capacitances.

It's possible, but obviously nobody is doing it!

On the other hand - impossible to reach the reliability of a PTP with a PCB. Heavy parts like a .68/160V Sozo or Mustard fixed on a tiny 'glued' copper trace... that must break earlier or later! I wouldn't trust!

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rockstah
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Post by rockstah » Tue May 23, 2006 11:50 am

Andy why do u say its bullshit? if i remember correctly this is not the first time u have slammed Gerald Weber. im wondering why... i mean shiat dude, i have all of his books and all of his videos... is it just a waste of time... i have learned alot from his writtings... so do tell.

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Post by Flames1950 » Tue May 23, 2006 4:56 pm

When I say it's bullshit, his example is almost always implying that these capacitance issues do not exist with a PTP layout/turret board.........that's just not true.......two conductors with a dielectric between them make a capacitor of some degree, whether the dielectric is epoxy or air, and sloppy layout or cramped space on either compounds the issue. All other things equal in the layout, you probably have different capacitances, but they are there nonetheless.

I'm not trying to say he's exactly "wrong" Mark, but as is often the case he puts a spin on the facts to sway you to his point of view -- that's all. I'd prefer to hear the facts without the spin from guys in his position.

He's still not at Aspen Pittman's level yet though......... :wink:
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Post by rockstah » Tue May 23, 2006 5:04 pm

Flames1950 wrote:When I say it's bullshit, his example is almost always implying that these capacitance issues do not exist with a PTP layout/turret board.........that's just not true.......two conductors with a dielectric between them make a capacitor of some degree, whether the dielectric is epoxy or air, and sloppy layout or cramped space on either compounds the issue. All other things equal in the layout, you probably have different capacitances, but they are there nonetheless.

I'm not trying to say he's exactly "wrong" Mark, but as is often the case he puts a spin on the facts to sway you to his point of view -- that's all. I'd prefer to hear the facts without the spin from guys in his position.

He's still not at Aspen Pittman's level yet though......... :wink:
i hear ya Andy. i was just using logic and it just seems to me that it would be more so with PCB than PTP - thats all - what do u think his motives are to say things like LCR and Illinois caps are not good and TECH , SPrague caps should be used in their place? u think he just trying to sell what he can get - i mean it does come as a surprise to me heariung his view on LCR caps but if it was false dont you think he would worry about being called on it? still learning here.
Mark

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Post by Flames1950 » Tue May 23, 2006 8:02 pm

I don't understand his crusade against LCR caps. I mean, he is THE ONLY person I've heard say anything bad about using them. If they were junk I'd have to believe the word would be around and they wouldn't be fetching up to $35 a can.....

Illinois I guess I have always equated with Radio Shack quality, mass purchased cheapos, but I have no real proof to back that up.
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Post by rockstah » Tue May 23, 2006 8:10 pm

Flames1950 wrote:I don't understand his crusade against LCR caps. I mean, he is THE ONLY person I've heard say anything bad about using them. If they were junk I'd have to believe the word would be around and they wouldn't be fetching up to $35 a can.....

Illinois I guess I have always equated with Radio Shack quality, mass purchased cheapos, but I have no real proof to back that up.
i hear ya but again he states they do not do a good job of filtering out dc ripple also says they will not last. so i ask do you think that he would lie about it or have some hidden agenda.. im only continueing on this becuase it seems its not the first i have heard about Gerald being... umm wrong from you ( also keep in mind i totally respect your input Andy)and im wondering if there is anything to back it up with.. the next time i talk to him on the phone i plan on asking what his take is exactly on this subject and why. he is always very open. i just dont udnerstand all the animosity(sp) towards Gerald Weber.

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Post by Flames1950 » Tue May 23, 2006 10:05 pm

rockstah wrote:
Flames1950 wrote:I don't understand his crusade against LCR caps. I mean, he is THE ONLY person I've heard say anything bad about using them. If they were junk I'd have to believe the word would be around and they wouldn't be fetching up to $35 a can.....

Illinois I guess I have always equated with Radio Shack quality, mass purchased cheapos, but I have no real proof to back that up.
i hear ya but again he states they do not do a good job of filtering out dc ripple also says they will not last. so i ask do you think that he would lie about it or have some hidden agenda.. im only continueing on this becuase it seems its not the first i have heard about Gerald being... umm wrong from you ( also keep in mind i totally respect your input Andy)and im wondering if there is anything to back it up with.. the next time i talk to him on the phone i plan on asking what his take is exactly on this subject and why. he is always very open. i just dont udnerstand all the animosity(sp) towards Gerald Weber.
I don't know what he would have to gain by lying about it, nor of any hidden agenda he might have (unless he's got a huge stash and wants to scare evryone away from any others he could hoard?)

And again, it's not that he is necessarily "wrong" but he sure likes to put a spin on things to shape your opinion. Believe me, I still find lots of useful stuff in his books too, but like Aspen Pittman's writing you get to sort through the material with a grain of salt.
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Post by rockstah » Wed May 24, 2006 2:07 pm


Dear Mark,
Do a listening test, but only do it at loud volumes. LCR's sound fine at low
volumes because filtering is a function of current. More current takes a
better filter. LCR cap will not remove the ripple that occurs when AC is
rectified to pulsating DC. The 120 Hz pulse will be in the power supply and
modulate the signal path.

Do a little experiment so you will be able to speak with authority on this
subject. Record the sound with LCR's on one track of a stereo recorder or
multitrack recorder. Notice the ugly, out of tune sound and the lower
non-harmonic note that moves with the note you are playing, but in a
non-harmonic way. Pay particular attention to the notes A and B flat. You
must turn the amp up to overdrive condition to hear this. When the amp is
drawing a lot of current, the LCR's will not rid the power supply ripple and
it is clearly audible as an out of tune sound underneath the note and a
lower but non-harmonic pitch.

Now change the filters to F&T and do the same test. Turn the amp up and
listen. You can do an overdub recording of this on a second track. Notice
how the notes sound in tune when overdriven. Play and A and a B flat. Notice
how clear the harmonics are and how there is no out of tune sound.

At this point, you should know why I don't like LCR caps. If you aren't
convinced, play both tracks into a mixer and mute one track. While it is
playing, unmute that one and mute the other so you can switch back and forth
and remember what the other one sounded like. Each time, one track is muted
and the other unmuted. Or turn the balance control on the stereo amp to the
left and listen, then to the right and listen. Which one do you prefer? Does
the one that is in tune sound better to you. Me too.

Why does Marshall use LCR? Because Marshall is a Brit company and LCR is
made in Britain. They have always used British parts unless the parts are
not available in Britain. I don't think Brits like dealing with Germans
anyway. Remember Germany sank many British ships and bombed London and
killed many British people's parents and grandparents and there is not a
great deal of love lost for importing expensive German parts over locally
produced cheap British parts. With a big manufacturing company like
Marshall, cheaper local is better than more expensive German.

Kindest Regards,
Gerald

----- Original Message -----
From: "Mark Abrahamian" <mark@markabrahamian.com>
To: <gerald@kendrick-amplifiers.com>
Sent: Tuesday, May 23, 2006 7:14 PM
Subject: LCR Caps


> Gerald,
>
> whats up? man I have to tell you I constantly get crap about the fact that
> you say LCR caps are shit. I have seen you mention many times in your
> writings that they do not do a good job of filtering out dc ripple.
> everyone
> always argues then why are they in every marshall? why is Gerald the only
> one that says this? I use f&t caps and sprague and have stayed away from
> LCR
> based on your words.
>
> can u elaborate on the subject some for me please?
>
> Mark
>

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