Fredde

[quote name='Bigwan' timestamp='1395750688' post='2405735'] Yeah that's what I wondered - did the response drop like a stone below 100Hz or not. Thanks for answering that! What's prompting the 6L6 redesign, if you don't mind me asking? I'd considered a cathode-biased 18 watt push-pull output for my own design with a suitable dummy load that was defeatable so you could use the pre for practice. [/quote] The redesign is mostly because I think the distortion of the push-pull triode when overdriven is a bit harsh and sudden. I want to try how a real power tube sounds at the output. Maybe we should move this discussion to some other thread, I'm starting to feel a bit like a hi-jacker...

[quote name='Bigwan' timestamp='1395746636' post='2405679'] Brilliant work! Been in the planning stages for a DIY preamp for a LONG time myself, and this is something I'd considered. The specs of the Hammond transformers put me off though - do you find they produce enough bass? The specs suggest they're very much guitar orientated with a low frequency cutoff of around 100Hz. [/quote] No problem with the bass response, I usually keep the bass dial at around 50% and that's plenty for me. Bass frequency cutoff figures for transformers (and speakers etc.) are not very informative as they only tell the frequency at which the curve starts dropping, not how steep the drop is. But I will have to replace the transformer anyway whe I go for the 6L6 single ended design, and the planned trafo (Hammond 1760C) has a low cutoff of 70Hz.

[quote name='LukeFRC' timestamp='1395687693' post='2405142'] that's a really nice design there, loved looking at the schematic - geekily want to know what the preamp's modelled on, how does it sound? - also the small power stage - great idea - is that an original idea to implement it in a preamp? thanks for sharing. [/quote] Thanks! The preamp is a fairly common design found in lots of amps (the Alembic F2-B for one). The only uncommon thing is the rotary-switched mid capacitor (straight copy from a Weber Amp Kit schematic, probably a copy from something else), a very nice feature to have in a bass amp. The small power stage idea is not my invention, but it doesn't seem to be very common. I chose this approach as I wanted a tube head sound (which includes the power stage and output trafo), but no way I'm going to pay for and haul around an all-tube head with enough power to drive the fEARful cab. I'm still experimenting, and as I said, I'm going to redesign the power section for a 6L6gc and see how that works out.

[quote name='LukeFRC' timestamp='1395680877' post='2405029'] go on tell us more about that pre! what's the design based on? [/quote] It's my own design, inspired by lots of other designs. The design concept is that it has a small power stage (padded to line level) to sound more like a real tube head. The power stage is currently a push-pull ecc99 (idea taken from the Firefly DIY amp project), but I intend to swap it to a SE 6L6GC. Some closeups: The schematic if someone's interested: [url="http://goo.gl/kbtA9k"]http://goo.gl/kbtA9k[/url]

Thanks guys! [quote name='gafbass02' timestamp='1395619067' post='2404512'] That jazz is giving me funny feelings, like when I used to climb the rope in gym class. [/quote] Haha,yes I know what you mean

My upgraded rig: Tube preamp (DIY) into Peavey IPR 1600 into fEARful 15/6.

[quote name='iconic' timestamp='1354447974' post='1885972'] 1983....are those the ones with machine head bullet type truss rod adjustment, as opposed to body end.....or did I dream that? [/quote] You must have dreamt it. On AV Precisions, reverse tuners and body end "remove neck to adjust"-type truss rod nut is the norm, and has always been AFAIK.

By choice definitely. My guitar playing is limited to hand strummed chords of well known songs on a nylon string acoustic, and my audience is then usually my (very young) sons or a more or less intoxicated group of partying friends.

My new 1973 Jazz!

Amplug + headphones. It's a lot easier to pick out separate instruments using headphones for some reason. Sometimes I do it while at work, using my VirtualBass web app: [url="http://subsite.tilaa.eu/virtualbass/"]http://subsite.tilaa.eu/virtualbass/[/url] and have the song ready for band rehersal in the evening.