MHartman SSS layout questions

[Bombacaototal]

The high filter on the MCE isn't supposed to have a join between positions 6 & 7. And yes, it's missing the 100k resistor.

@krinkle: I changed the capacitors before the filters.

Aaron

Do you mean something like this (attached) as far as the join between 6&7 for the high filter?

[Krinkle]

Yes, that's the way I see it in the JSCH.

[Bombacaototal]

I am thinking about going for these filters http://www.mouser.co.uk/Search/m_Produc ... R2511F-17S or these ones http://eu.mouser.com/Search/ProductDeta ... R2921F-17S

[Bombacaototal]

I've been comparing the JSCH and MCE. There are several discrepancies but another thing I cannot understand on the JSCH is why on the high filter the .01 is in the middle together with the 1000pf and not at the end?

[Bombacaototal]

Should the 1st position on each filter (1st on the left) be:
a) high: .003 to ground
b) low: 39k

With the last position (7th, last on the right) being:
a) high: .01
b) low: 390k


Or is it the other way around

[Krinkle]

I built from the MCE and my filter circuit is backwards. So I think it should opposite of the MCE. Somebody here posted a SIM of it in another thread and it is numbered correctly.

[Bombacaototal]

I built from the MCE and my filter circuit is backwards. So I think it should opposite of the MCE. Somebody here posted a SIM of it in another thread and it is numbered correctly.

Thanks a lot for the reply

By backwards do you mean, as you turn the step filter clockwise from bypass position (9 o'clock) do you have less or more (bass for low filter / treble for high)?

[Krinkle]

I built my Low filter with a 1MA pot as per one of the alternate diagrams here on TAG somewhere. The bass increases as I turn the pot to 0.

I built my High filter with the typical 7 position switch, and from 9 o'clock to 3 o'clock it gets less bright each time I switch, until I get to the last position (bypass) at 3 o'clock, then it gets bright again. Keep in mind though that my bypass is wired as per the incorrect MCE, not the JSCH. When I switched over to JSCH (which I thought was too bright and didn't like so I put it back to MCE), I don't remember if the bypass position was brighter than the position just before it or not.

I am probably going to put it back to JSCH and play around with the 0.001 and 0.1 values (as per Aaron) to see if I can get something to my liking. I'll let you know when I do it.

I will be changing from a pot to a switch for the Low as well, because of what I mentioned above.

[Bombacaototal]

Thanks! It indeed helps

I think I am on the right direction

Attached I got the alternative version of the filter from MCE and matched/corrected against the JSCH

I think it is free of errors but let me know if you spot anything

[Krinkle]

Thanks! It indeed helps

I think I am on the right direction

Attached I got the alternative version of the filter from MCE and matched/corrected against the JSCH

I think it is free of errors but let me know if you spot anything

I'll check it as I have to correct the schematic I am editing for my build. I'm going to order another switch and build it this way in my Bassman mod, just not sure how soon that will be.

[martin manning]

Take a look at the version I posted this morning in the files section.

[Colossal]

Take a look at the version I posted this morning in the files section.

Nicely done, as usual, Martin

[Bombacaototal]

Just noticed that on the Japanese schematic there is a note in japanese between "red" and 39k which means "turn to the right". Taking this into account it may be that that position is actually the first one

The writing close to the 390k reads "confused". Not a great sign, so assume errors?

The note on the high filter in katakana says "sprague" = .01uF

[Bombacaototal]

Take a look at the version I posted this morning in the files section.

Thanks, I will check it out

[Krinkle]

Take a look at the version I posted this morning in the files section.

Excellent. That will save me some time in my new build, thanks for sharing.