Bottlehead Forum Welcome! Need support, you got it. Or share you ideas and experiences.

---

[ Follow Ups ] Thread: [ Display  All  Email ] [ Bottlehead Forum ]

---

[ Alert Moderator ] [ Edit ] [ Delete ]

---

Re: Hammond 193B and 193C. (plus 157J) - What is the significance of the self-resonance in both power supply and parafeed applications? Have you built

4.54.14.236

Posted by freddyi on November 27, 2000 at 20:11:46

In Reply to: Hammond 193B and 193C. (plus 157J) posted by Tom §. on November 27, 2000 at 11:34:31:

Hi Tom

does the 'in-band' resonance reder these chokes useless for parafeed?

also - I assume there's not much problem in pi-filters (?)

in another forum I asked you abut 'maximizing the Hammond output transformers in two cases and wonder if you might agree on these methods and results?:

(1)Case of a zero feedback amp (or feedback amp with the 1st stage running 'free') = I would assume either partial cap or RC bypassing of the 1st stage cathode resistor will provide the 'lift' need to compensate for the Hammond transfomer's HF rolloff - can this bit of eq make the Hammond 'competitive' with the pricier transformers and squeak better sonics out of the unit?

(2)Case of feedback amp using loop nfb from the output transformer's secondary - will a RC 'snubber across the whole transformer primary allow deletion of the RC 'lead-lag; network in circuits where the driver/inverter gain is low sucha s a gain/split-load inverter or a cathode-coupled inverter with the nfb injected to one side ala Fender?

many thanks - very cool tests on the Hammond chokes - have you also tested Hammond and Lundahl output iron under dc current?

Freddy

This post is made possible by the generous support of people like you and our sponsors:

Schiit Audio

---

[ Top of Page ] [ Contact Us ] [ Support/Wish List ] [ Copyright © 2025, Audio Asylum, all rights reserved ]

---

[ General ] [ Speakers ] [ Tubes ] [ Vinyl ] [ Digital ] [ Hi-Rez ] [ Video Asylum ] [ Cables ] [ Tweaks/DIY ] [ Music ] [ Films ]

---