John Mayer Two Rock build

[M Fowler]

Ebay sellers

[Bombacaototal]

Ebay sellers

Thanks

[Bombacaototal]

Those robin egg blue are Electra RN70D

There are metal film IRC, Electra, Mepco, KOA, Dale CCF60, Dale CMF60, and RN65D.

Holy Grail of Resistor types

BEYSCHLAG CF resistors
DRALORIC CF resistors
PIHER CF resistors

Many use Xicon CF resistors but a few people have said they don't like them sound wise.

Maybe Tony Albany or others will comment.

What are the holy grail MF? Mepco/Electra?

[ToneMerc]

What are the holy grail MF? Mepco/Electra?

In the context of what we call 1st, 2nd and 3rd generation amps, it's Electra.

TM

[Bombacaototal]

What are the holy grail MF? Mepco/Electra?

In the context of what we call 1st, 2nd and 3rd generation amps, it's Electra.

TM

Indeed! Thanks a lot. I've been struggling to find the correct values from Electra tho. Will keep on hunting

[ToneMerc]

What are the holy grail MF? Mepco/Electra?

In the context of what we call 1st, 2nd and 3rd generation amps, it's Electra.

TM

Indeed! Thanks a lot. I've been struggling to find the correct values from Electra tho. Will keep on hunting

They haven't been made in 46 years, good luck!

TM

[Bombacaototal]

What are the holy grail MF? Mepco/Electra?

In the context of what we call 1st, 2nd and 3rd generation amps, it's Electra.

TM

Beautiful board! Are the CF pihers? All MF are Electra. Orange Drops 6PS. What else is in there?

[ToneMerc]

What are the holy grail MF? Mepco/Electra?

In the context of what we call 1st, 2nd and 3rd generation amps, it's Electra.

TM

Beautiful board! Are the CF pihers? All MF are Electra. Orange Drops 6PS. What else is in there?

Thanks....Yes, except for the PI cathode,which is a Beyschlag. Most of the 6PS orange drops are the older original di-film construction caps that one will find in the older Dumble amps. The cathode caps are the Sprague TE hi temp caps that I like to use.

TM

[Bombacaototal]

In the context of what we call 1st, 2nd and 3rd generation amps, it's Electra.

TM

Beautiful board! Are the CF pihers? All MF are Electra. Orange Drops 6PS. What else is in there?

Thanks....Yes, except for the PI cathode,which is a Beyschlag. Most of the 6PS orange drops are the older original di-film construction caps that one will find in the older Dumble amps. The cathode caps are the Sprague TE hi temp caps that I like to use.

TM

Really nice. Thanks for the details

Are all Pihers rated 2W?

Any reason you chose the beyachlag for the PI cathode?

Do the Sprague TE (I assume new production) differ a lot from the Sprague Atom (also current production) for cathodes?

From which brand do you source higher rated MF (ie 5W)?

[ToneMerc]

Are all Pihers rated 2W?

Any reason you chose the beyachlag for the PI cathode?

Do the Sprague TE (I assume new production) differ a lot from the Sprague Atom (also current production) for cathodes?

From which brand do you source higher rated MF (ie 5W)?

No, 1/8 to 4W
Yes, it simply physically fit better there that a 1W Piher
Yes, higher temp rating and lower ESR, IIRC
Usually Dale or Ohmite

TM

[Bombacaototal]

Are all Pihers rated 2W?

Any reason you chose the beyachlag for the PI cathode?

Do the Sprague TE (I assume new production) differ a lot from the Sprague Atom (also current production) for cathodes?

From which brand do you source higher rated MF (ie 5W)?

No, 1/8 to 4W
Yes, it simply physically fit better there that a 1W Piher
Yes, higher temp rating and lower ESR, IIRC
Usually Dale or Ohmite

TM

Do you by any chance know if the Mepco resistors P/N: RLR20C1003GS similar to MF7C?
I am planning to use it as a plate load and tonestack slope

[ToneMerc]

Do you by any chance know if the Mepco resistors P/N: RLR20C1003GS similar to MF7C?
I am planning to use it as a plate load and tonestack slope

Actually I do because I curious and so was the person that was selling vintage resistors, so we dissected Electra and the proceeding M-E resistors. Long story, short is that the Electras with the end cap humps are different.


TM

[Bombacaototal]

Do you by any chance know if the Mepco resistors P/N: RLR20C1003GS similar to MF7C?
I am planning to use it as a plate load and tonestack slope

Actually I do because I curious and so was the person that was selling vintage resistors, so we dissected Electra and the proceeding M-E resistors. Long story, short is that the Electras with the end cap humps are different.


TM

Thanks for the note. Interesting, so they are indeed different

My project uses a plate load of 100k. I have a choice between electra rn60c 93.1k 1/2 watt or the Mepco I mentioned above (RLR) 100k 1/2watt.
Which one would you go for?

[ToneMerc]

Do you by any chance know if the Mepco resistors P/N: RLR20C1003GS similar to MF7C?
I am planning to use it as a plate load and tonestack slope

Actually I do because I curious and so was the person that was selling vintage resistors, so we dissected Electra and the proceeding M-E resistors. Long story, short is that the Electras with the end cap humps are different.


TM

Thanks for the note. Interesting, so they are indeed different

My project uses a playe load of 100k. I have a choice between electra rn60c 93.1k 1/2 watt or the Mepco I mentioned above (RLR) 100k 1/2watt.
Which one would you go for?

Don't make this harder than it needs be, there's lot of adequate MF resistors. So, just use the 100K.



TM

[Bombacaototal]

Actually I do because I curious and so was the person that was selling vintage resistors, so we dissected Electra and the proceeding M-E resistors. Long story, short is that the Electras with the end cap humps are different.


TM

Thanks for the note. Interesting, so they are indeed different

My project uses a playe load of 100k. I have a choice between electra rn60c 93.1k 1/2 watt or the Mepco I mentioned above (RLR) 100k 1/2watt.
Which one would you go for?

Don't make this harder than it needs be, there's lot of adequate MF resistors. So, just use the 100K.



TM

Perfect! Thanks again

Would the Mepco be worth the extra money compared to a Vishay RN65D or a PR9372?