catalin gramada

Hi. You Dynacord is sort of HiFi amp.In consequence they used lot of negative feedback to improve the liniarity (18-20db as it looks-I think) I bet you can cut to 10-12 db arround and still can have good bass not boomy reponse. So, replace the feedback network with some more convenable in 1:10 to 1:15 ratio should be enough.( Keep in mind some bias voltage is developed over series feedback resistor and secondary winding so better to replace with sort of 2k2 bypassed with 100uF in first half ecc81 cathode and add 100ohm to ground. Use 1k-1.5k from junction between 2k2 and 100ohm and run to 8-16 ohm secondary tap. Now you should have enough room from you 6sl7 b15 type preamp 4Vpk arround think to push you Dynacord power stage to the proper drive. You can squeeze a litle bit more excursion if you change 220k from cathodyne grid to 470k. Sorry for my broken english, hope it have sense. Cheers

Hello and Thank You all [quote name='gary mac' timestamp='1425279419' post='2705707'] The cab project is looking good. What finish are you planning for it? [/quote] Well...have to think if worth it. The cab sound great (sort of Sunn 200 clone, speakers are British made -Fane Axa 15B)..but made from thick baltic birch ply is heavy as hell - over 180 pounds, any intention to move it arround is a challenge so I think I'll given up. Cheers Catalin

Greetings from Romania. enthusiast hobbist here. My last bass projects, work in progress: Best Regards Catalin