Pentode (EF86) pre-amps and combo's?

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AC Cobra
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Re: Pentode (EF86) pre-amps and combo's?

Post by AC Cobra »

Will do. The 4th guitar on the list is mine (provided it dosent get bumped back by more orders) I also need to free up the CNC so I can cut out my chassis, or use one of the mills at my day job.
Thanks for the encouragement.
There will also be a video of the 2 guitara we are building at this moment, but it will probably be recorded with amplitube so not entirely revalent to 18 watt.com
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dotfret
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Re: Pentode (EF86) pre-amps and combo's?

Post by dotfret »

I noticed this a while back, but forgot to mention it. If you look up the data sheet for the Z729 (which is GEC-MOV talk for EF86),

http://www.mif.pg.gda.pl/homepages/fran ... 29_GEC.pdf" onclick="window.open(this.href);return false;

there is a section on af operation with lots of handy hints on how to minimise hum and microphony. Particularly, you will find there is a sentence suggesting that connecting the screen to ground via a paper capacitor of at least 0.1uF stops a lot of noise.

Worth a read.
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Re: Pentode (EF86) pre-amps and combo's?

Post by JMPGuitars »

Huh. Apparently I never posted my results. The RFT EF86 tubes are excellent. However, there are plenty of fakes out there, so be careful if you're looking for an RFT tube.

Here's a couple demos with an RFT EF86 in a combo:


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Re: Pentode (EF86) pre-amps and combo's?

Post by Bieworm »

F***in great tone Josh!!!
When did you record this?
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"THIS should be played at high volume..preferably in a residential area"

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Re: Pentode (EF86) pre-amps and combo's?

Post by JMPGuitars »

Bieworm wrote:
Mon 04/15/24 1:46 am
F***in great tone Josh!!!
When did you record this?
lol, thanks. Uhhhhh, 9 years ago. Somebody liked one of my posts so the thread pooped up for me. 🤣
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'I installed a skylight in my apartment yesterday... The people who live above me are furious.' - Steven Wright

Modern Ground Schemes
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B+ Voltage Reduction
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