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
Re: Pentode (EF86) pre-amps and combo's?
Posted: Sat 03/15/14 12:03 pm
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),
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.
Re: Pentode (EF86) pre-amps and combo's?
Posted: Sun 04/14/24 9:01 am
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:
Re: Pentode (EF86) pre-amps and combo's?
Posted: Mon 04/15/24 1:46 am
by Bieworm
F***in great tone Josh!!!
When did you record this?
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.
Re: Pentode (EF86) pre-amps and combo's?
Posted: Sun 04/28/24 12:47 pm
by dwetherby
Hey so I don’t know how to post on this but I bought this amp from this guy for like 150 and sometimes it just sputters and gets a tone drop I found a cold sodder on a preamp tube, I fixed it and don’t get a drop out but just sounds kind of muddy. I’m also wondering about the resistors on the tubes and how schematics I look at don’t have the resistors going off to the board but they jump pins??? Also all the schematics I see are 3 ax7 but this one has two? I know nothing but to discharge the caps to not get shocke. Does this look right to you guys? Could be a tone pot issue possibly? Guy I bought it from said he built it off this site.
Also this is all at volume at about 3 (can’t tell if gain is volume or volume is volume…kind of all sounds the same) to keep up with band..at low levels it sounds great up to 2
Edit:
Just added two pictures of the pots for volume bass gain and Treb…I feel like my other amps I have and other amps I’ve seen don’t have resistors and stuff on the pots? A resistor on the 1/4” input??? Does this look right or excessive? Sorry and thank you in advance
