|
Post by Chilly Gibbons (Todd T.) on Dec 26, 2017 18:57:34 GMT -7
Greetings! I’m putting together a 5e1 and am using a larger 15 watt SE output tranny that has 5k and 8k primaries. Can anyone describe what difference using either of these (5k or 8k) would make or sound like. The rest of the circuit is stock/classic 5e1 (6v6 for now) except I’m playing around with negative feedback and leaning towards eliminating it altogether. Many thanks!
|
|
|
Post by purpletele on Dec 26, 2017 23:00:56 GMT -7
Greetings! I’m putting together a 5e1 and am using a larger 15 watt SE output tranny that has 5k and 8k primaries. Can anyone describe what difference using either of these (5k or 8k) would make or sound like. The rest of the circuit is stock/classic 5e1 (6v6 for now) except I’m playing around with negative feedback and leaning towards eliminating it altogether. Many thanks! Check it out! www.tdpri.com/threads/5f1-impedance-5k-or-8k.389784/
|
|
|
Post by Chilly Gibbons (Todd T.) on Dec 27, 2017 16:34:17 GMT -7
Thanks Purple. Using the rough formula Z=Va^2/Pa to estimate primary impedance, it turned out that the tubes I really want to use at the voltages I’m running (5881, 6v6, and possibly an EL34) are closest to 8k. I chose wisely for once. Thanks again!
|
|
|
Post by purpletele on Dec 27, 2017 20:29:33 GMT -7
Thanks Purple. Using the rough formula Z=Va^2/Pa to estimate primary impedance, it turned out that the tubes I really want to use at the voltages I’m running (5881, 6v6, and possibly an EL34) are closest to 8k. I chose wisely for once. Thanks again! If you get into a bind you can check out the Hoffman web page. The guys on that forum are really helpful if you present questions in a format that they can easily review and comment. It is quite amazing to follow the progress and issues of other solder sniffers,
|
|
|
Post by premiumplus (Dave) on Dec 28, 2017 6:17:36 GMT -7
Great stuff on Hoffman. When you get it finished, please put some clips and pics up for us. The only Fender style amp I've built was a 5E3 back in '08 or so, and it came out great.
|
|
|
Post by Chilly Gibbons (Todd T.) on Dec 29, 2017 11:41:03 GMT -7
I have a working chassis and some photos. I guess I need to establish an off-site image hosting service, then point to it from here. Will return.
|
|
|
Post by Chilly Gibbons (Todd T.) on Jan 1, 2018 13:03:04 GMT -7
I hope this works. Here are some image links. Bright cap has since been removed. 5e1
|
|
|
Post by premiumplus (Dave) on Jan 1, 2018 16:36:20 GMT -7
Nice build, very clean. One suggestion, try to get some space between the output tube cathode resistor and it's associated bypass capacitor. Capacitors don't like heat.
|
|
|
Post by Chilly Gibbons (Todd T.) on Jan 1, 2018 16:42:27 GMT -7
Thanks Dave, I did float the cap a couple of mm above the resistor. Just can’t see it in the photos.
|
|
|
Post by purpletele on Jan 1, 2018 17:55:32 GMT -7
I hope this works. Here are some image links. Bright cap has since been removed. 5e1Looks good, how does it sound.
|
|
|
Post by Chilly Gibbons (Todd T.) on Jan 2, 2018 16:38:36 GMT -7
Sounds good, a bit stiff though with all of the large filters plus a choke. I don’t want to mess with it much more until I get the 1x10 cab delivered and play it awhile through the alnico gold. I have it temporarily in a 1x8 tweed with an 8” Jupiter Ceramic. Very large sounding with great bell tones.
|
|