paul_5 Posted February 17, 2016 Share Posted February 17, 2016 [quote name='ahpook' timestamp='1453827039' post='2963193'] One thought - how does one increase the gain of a JFET boost like the Stratoblaster ? [/quote] Run a capacitor (4.7uf or 10uf) in parallel with the resistor that goes froSource to Groung - that'll get you more gain. Obviously that sort of value will most likely be an electrolytic ! Polarised cap,so make sure that the cathode goes to ground, and Bob's your Mother's brother. Quote Link to comment Share on other sites More sharing options...
ahpook Posted February 17, 2016 Share Posted February 17, 2016 (edited) [quote name='paul_5' timestamp='1455744408' post='2982115'] Run a capacitor (4.7uf or 10uf) in parallel with the resistor that goes froSource to Groung - that'll get you more gain. Obviously that sort of value will most likely be an electrolytic ! Polarised cap,so make sure that the cathode goes to ground, and Bob's your Mother's brother. [/quote] Aha ! I'll give that a whirl Edited February 17, 2016 by ahpook Quote Link to comment Share on other sites More sharing options...
paul_5 Posted February 17, 2016 Share Posted February 17, 2016 [quote name='ahpook' timestamp='1455749397' post='2982185'] Aha ! I'll give that a whirl [/quote] Smaller caps will deliver less gain, so you might want to socket and find a value that works for you. Quote Link to comment Share on other sites More sharing options...
ahpook Posted February 18, 2016 Share Posted February 18, 2016 [quote name='paul_5' timestamp='1455750453' post='2982194'] Smaller caps will deliver less gain, so you might want to socket and find a value that works for you. [/quote] Exactly my plan Quote Link to comment Share on other sites More sharing options...
Dood Posted February 18, 2016 Share Posted February 18, 2016 [quote name='Bigwan' timestamp='1455739855' post='2982043'] Spent a wee while looking at the Boughton L+HPF and think I have the circuit figured out if you're interested dood. Could draw it up for you. Will be adding one to my own "to do" list! Speaking of my "to do" list, it doesn't seem to be getting any shorter... And just to add to it I've ordered a Mad Professor Blueberry clone kit from Pedalparts. No intention of building the Mad Professor version but it's a good starting point for the bearfoot or bjfe version. A few part omissions and a bit of inventive wiring will do the business! [/quote] You've got the L+HPF? How are you finding it? Yes, yes please I would love to see a schematic for it Thank you so much! Quote Link to comment Share on other sites More sharing options...
Bigwan Posted February 18, 2016 Share Posted February 18, 2016 [quote name='dood' timestamp='1455791950' post='2982415'] You've got the L+HPF? How are you finding it? Yes, yes please I would love to see a schematic for it Thank you so much! [/quote] No don't have one, just been following the breadcrumbs! It's 2 Sallen-Key filters in series, probably preceded by a buffer stage and followed with a volume control. A bit of simulation with standard ganged-pot, resistor and cap values plugged into an equal component filter design gets VERY close to the cutoff frequencies that Azure Skies quotes. He's added a volume control as the design has inherent gain (as-in volume boost not distortion). I'll draw up something very quickly Quote Link to comment Share on other sites More sharing options...
Bigwan Posted February 18, 2016 Share Posted February 18, 2016 (edited) Apologies for the rushed nature of this - just hacked a few old schematics I had together to give you the gist of the thing... [attachment=212628:for dood.jpg] The 11k+Vr2 and 5.6k+Vr1 are a standard resistor in series (therefore setting the minimum value) with one half of a ganged/stereo pot as each filter needs 2 values to be changed equally at the same time. Just need to tack a volume control on the end somewhere to cut the added volume down. Or not if you've got something appropriate next in the chain to do it for you. Edit: Oh and the Broughton just uses a TL074 quad opamp. Edited February 18, 2016 by Bigwan Quote Link to comment Share on other sites More sharing options...
Twigman Posted February 18, 2016 Share Posted February 18, 2016 I'd like to get into this pedal building malarkey...the only pedal i want at the moment is a more flexible compressor...with adjustable ratio, threshold, attack, release, input level and make up gain....so that's six knobs!!! is there a DIY project about on the web that's voiced for bass that covers this? Quote Link to comment Share on other sites More sharing options...
Dood Posted February 18, 2016 Share Posted February 18, 2016 [quote name='Bigwan' timestamp='1455795173' post='2982458'] Apologies for the rushed nature of this - just hacked a few old schematics I had together to give you the gist of the thing... [attachment=212628:for dood.jpg] The 11k+Vr2 and 5.6k+Vr1 are a standard resistor in series (therefore setting the minimum value) with one half of a ganged/stereo pot as each filter needs 2 values to be changed equally at the same time. Just need to tack a volume control on the end somewhere to cut the added volume down. Or not if you've got something appropriate next in the chain to do it for you. Edit: Oh and the Broughton just uses a TL074 quad opamp. [/quote] Yup, I understand that! Brilliant! Thank you! In comparison, here's the Rolls Crossover offering HPF, LPF and about 20dB gain boost as I understand it. http://www.rolls.com/pdf/IS_SX21.pdf Quote Link to comment Share on other sites More sharing options...
tauzero Posted February 19, 2016 Share Posted February 19, 2016 [quote name='Bigwan' timestamp='1455795173' post='2982458'] Apologies for the rushed nature of this - just hacked a few old schematics I had together to give you the gist of the thing... [attachment=212628:for dood.jpg] The 11k+Vr2 and 5.6k+Vr1 are a standard resistor in series (therefore setting the minimum value) with one half of a ganged/stereo pot as each filter needs 2 values to be changed equally at the same time. [/quote] IIRC that gives a 12dB/octave rolloff for both HPF and LPF - you can simply cascade two identical filters to give a 24dB/octave roll-off which might be better, at least for the HPF if you're looking at thump elimination. Quote Link to comment Share on other sites More sharing options...
Bigwan Posted February 19, 2016 Share Posted February 19, 2016 [quote name='tauzero' timestamp='1455900369' post='2983507'] IIRC that gives a 12dB/octave rolloff for both HPF and LPF - you can simply cascade two identical filters to give a 24dB/octave roll-off which might be better, at least for the HPF if you're looking at thump elimination. [/quote] Yup, there's a thumpinator right there! The filter responses for that circuit aren't ideal, but close enough for the purpose. Quote Link to comment Share on other sites More sharing options...
danbowskill Posted February 19, 2016 Share Posted February 19, 2016 (edited) [quote name='Bigwan' timestamp='1455740968' post='2982062'] The Ginger is also on "ze list"... As is the Fairfield Barbershop (should have most of the bits for it lying around!). Looking forward to your Ginger pics. Did you use the board from Musikding? [/quote] i used Musikding yes, great prices :-) I do think i might have bitten to much off doing the Ginger as a first build project though :-( I have power etc (Led, switch n jacks work) but all i get is horrid static sounds? volume and gain work but no sounds ,just static buzz?. ive checked the components to the list/diagram i have and solder joints ......... all appear good (to me that is)?? doing my nut in a bit tbh ...........any ideas,anyone done the ginger? cheers[attachment=212773:IMG_20160219_194722.jpg][attachment=212774:IMG_20160219_194727.jpg][attachment=212775:IMG_20160219_195723.jpg] Edited February 19, 2016 by danbowskill Quote Link to comment Share on other sites More sharing options...
nick Posted February 20, 2016 Share Posted February 20, 2016 (edited) [quote name='danbowskill' timestamp='1455913096' post='2983668'] i used Musikding yes, great prices :-) I do think i might have bitten to much off doing the Ginger as a first build project though :-( I have power etc (Led, switch n jacks work) but all i get is horrid static sounds? volume and gain work but no sounds ,just static buzz?. ive checked the components to the list/diagram i have and solder joints ......... all appear good (to me that is)?? doing my nut in a bit tbh ...........any ideas,anyone done the ginger? cheers[attachment=212773:IMG_20160219_194722.jpg][attachment=212774:IMG_20160219_194727.jpg][attachment=212775:IMG_20160219_195723.jpg] [/quote] If you've checked solder joints, polarity of caps, leds & other components, no shorts to ground etc... Have you looked at the j-fets, are they OK? I've had issues previously with crap ones. Edited February 20, 2016 by nick Quote Link to comment Share on other sites More sharing options...
Dood Posted February 20, 2016 Share Posted February 20, 2016 [quote name='tauzero' timestamp='1455900369' post='2983507'] IIRC that gives a 12dB/octave rolloff for both HPF and LPF - you can simply cascade two identical filters to give a 24dB/octave roll-off which might be better, at least for the HPF if you're looking at thump elimination. [/quote] Maybe that sort of Thumpinator roll off would be beneficial, though for my useage I'd be looking at winding that filer point all the way up to around 300hz - But I don't want to build anything until I've tested the theory! Quote Link to comment Share on other sites More sharing options...
Bigwan Posted February 20, 2016 Share Posted February 20, 2016 (edited) [quote name='danbowskill' timestamp='1455913096' post='2983668'] i used Musikding yes, great prices :-) I do think i might have bitten to much off doing the Ginger as a first build project though :-( I have power etc (Led, switch n jacks work) but all i get is horrid static sounds? volume and gain work but no sounds ,just static buzz?. ive checked the components to the list/diagram i have and solder joints ......... all appear good (to me that is)?? doing my nut in a bit tbh ...........any ideas,anyone done the ginger? cheers[attachment=212773:IMG_20160219_194722.jpg][attachment=212774:IMG_20160219_194727.jpg][attachment=212775:IMG_20160219_195723.jpg] [/quote] The Ginger is a serious build for a first attempt! As mentioned it could be any one of a hundred things. Unfortunately remotely debugging something like this is extremely tricky. I'm planning building of these myself when I've finished my 3BOD build... And after payday! By the way danbowskill, is that a 125B or 1590B enclosure? Edited February 20, 2016 by Bigwan Quote Link to comment Share on other sites More sharing options...
danbowskill Posted February 20, 2016 Share Posted February 20, 2016 (edited) Gonna sound like a spaz here.........which 1s are the Jfets? Also how do you know which way to turn the caps for right polarity? I literally copied the parts list and photo shown in the ginger docs in this link.not fully clued up yet :-( I'm sure it's nothing major as I can notice the knobs working ( just no bass sounds) .... There is also no bass at all when effect is bypassed. http://www.musikding.de/ROG-Ginger-Ampsim-kit Thanks guys :-) Edited February 20, 2016 by danbowskill Quote Link to comment Share on other sites More sharing options...
danbowskill Posted February 20, 2016 Share Posted February 20, 2016 125b size bigwan Quote Link to comment Share on other sites More sharing options...
Bigwan Posted February 20, 2016 Share Posted February 20, 2016 Sounds like a wiring problem around the 3PDT footswitch. Should be passing signal on bypass. Quote Link to comment Share on other sites More sharing options...
danbowskill Posted February 20, 2016 Share Posted February 20, 2016 I've been over the wiring of the footwitch and using a daughter board for connecting it all appears correct? When I first wired it up I didn't use a daughter board and I hadn't placed a CLR before the Led .......it went pop,could that maybe of damaged the footswitch? Quote Link to comment Share on other sites More sharing options...
Bigwan Posted February 20, 2016 Share Posted February 20, 2016 Unlikely, although the switch could be a dud. Stranger things have happened. Have you tried directly wiring the input and output jacks to the pcb without the switch? Speaking from experience, boxing up a pcb before checking it is often optimistic! Quote Link to comment Share on other sites More sharing options...
danbowskill Posted February 20, 2016 Share Posted February 20, 2016 It's all very optimistic to be fair :-D........I'm determined to get it working,I'll post a pic in a month or 2 ;-) Quote Link to comment Share on other sites More sharing options...
paul_5 Posted February 20, 2016 Share Posted February 20, 2016 yup. I don't box stuff up (or even wire the switch) until I know the build is sound. Quote Link to comment Share on other sites More sharing options...
Bigwan Posted February 20, 2016 Share Posted February 20, 2016 Couldn't hold out any longer. Ginger kit ordered from Germany! And an enclosure for the h+lpf. Is there anywhere in the UK that does pre-drilled 1590B enclosures? Hate drilling!!! Quote Link to comment Share on other sites More sharing options...
Bigwan Posted February 23, 2016 Share Posted February 23, 2016 [quote name='dood' timestamp='1455800687' post='2982535'] Yup, I understand that! Brilliant! Thank you! [/quote] And a veroboard layout has pretty much been done for me! http://www.sabrotone.com/?p=3173 Just remove the noise making circuitry from the schematic, adjust cap and pot (and series resistor!) values around the 2 filter stages, and change up the last opamp stage to incorporate a volume control to the design and it's done. Should fit in a 1590b no problem. Quote Link to comment Share on other sites More sharing options...
Dood Posted February 23, 2016 Share Posted February 23, 2016 [quote name='Bigwan' timestamp='1456236192' post='2986873'] And a veroboard layout has pretty much been done for me! [url="http://www.sabrotone.com/?p=3173"]http://www.sabrotone.com/?p=3173[/url] Just remove the noise making circuitry from the schematic, adjust cap and pot (and series resistor!) values around the 2 filter stages, and change up the last opamp stage to incorporate a volume control to the design and it's done. Should fit in a 1590b no problem. [/quote] Crickey! That's great! Quote Link to comment Share on other sites More sharing options...
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