Fun-da-mental Posted February 10, 2014 Share Posted February 10, 2014 Hi all Although I've had my edb for a while now, it's not been out much. I regularly play in pit bands in theatre (usually on electric bass) and on the couple of shows where I took my stagg I was embarrassed by flat battery issues (usually accompanied by a loud tthhhhppp!) Anyways - had a night spare so thought I'd tackle the issue. Many years ago I completed a btec in electronic design and spent 20 years as an electronics service engineer -however please feel free to pick up from where I left off and let's develop this further. The current consumption of my standard preamp was 20ma It's now 3ma Here's what I did: 1. The first preamp chip is a tl072. Replace with a tl062. Still sounds good to me and no excessive hiss or noise 2. Disconnect the supply rails to the two LM386 power amp chips (pin 6 on each -heat and lift with a pin) 3. Put two cheap red LEDs in series with existing blue led With the mods the headphone socket will not work - you could introduce a switch to power up the lm386 if that was a problem to you. Personally I always found the headphone jack noisey and never used it. The series led mean that you get a true battery indicator. As the battery voltage falls from 9v the led stays full brightness until 6v - at which point it goes out. On my unit the preamp still worked right down to 3.2v so you would get plenty of warning. I have found that the tone at the jack output is unaffected by the modifications. I hope this is of help to someone. Cheers all 2 Quote Link to comment Share on other sites More sharing options...
LukeFRC Posted February 10, 2014 Share Posted February 10, 2014 can I just say. what a great first post! Quote Link to comment Share on other sites More sharing options...
ubassman Posted February 11, 2014 Share Posted February 11, 2014 Welcome! I have quoted your info in here which may be of interest with other modifications to Staggs http://basschat.co.uk/topic/6749-stagg/page__st__390__p__2330702__hl__stagg__fromsearch__1#entry2330702 Quote Link to comment Share on other sites More sharing options...
gareth Posted February 14, 2016 Share Posted February 14, 2016 So am I right in saying that when the blue light is on the battery is ok but when it is not on the battery needs replacing? Quote Link to comment Share on other sites More sharing options...
gareth Posted February 14, 2016 Share Posted February 14, 2016 So it's when the blue light goes out that the battery is flat? When the light is on and blue, the battery is ok? From an active/battery hating basschater Quote Link to comment Share on other sites More sharing options...
BassTool Posted March 6, 2016 Share Posted March 6, 2016 Great post! Thanks Quote Link to comment Share on other sites More sharing options...
pfretrock Posted March 7, 2016 Share Posted March 7, 2016 [quote name='LukeFRC' timestamp='1392068832' post='2364411'] what a great first post! [/quote] yes! I'm not familiar with the instrument, but wonder why there are two LM386 chips? Is one headphones out and the other line out? Would it help leaving the headphone chip unconnected if it is not used? Great mod. (I did 20 years electronics, now do software - easier to modify!) Quote Link to comment Share on other sites More sharing options...
zvirus Posted June 1, 2019 Share Posted June 1, 2019 (edited) Hi, Just did step 2 only and from 20mA it went to 7mA. Quote 2. Disconnect the supply rails to the two LM386 power amp chips (pin 6 on each -heat and lift with a pin) Re. Step 1. I have found on the internet that: Quote - TL062 is the low power version of the TL082. - TL072 is the low noise version of the TL082. I`m very shocked after I have found that my EDB Deluxe is quieter than my P-Bass or Jazz Bass. No hiss not a TINY bit of ANY noise! I did not bother do any shielding as preamp`s casing acts well as a shield Thanks For sharing this will prolong battery life by 3 times! I have cut the lugs with sharp blade. No heat used... (It`s one way ticket - you wont fix it back!) Edited June 26, 2019 by zvirus Quote Link to comment Share on other sites More sharing options...
Staggering on Posted June 1, 2019 Share Posted June 1, 2019 The Stagg I owned and the Yamaha SLB200 that I use now both have a power switch in the output jack and some owners are not aware of this and wonder why their batteries don't last. If the cable is plugged in the preamp is on. I assume from the work you have done that you know a lot about electronics and are aware of this but I thought I'd toss it out just so others with battery problems following this thread might find it useful before they look for other solutions. I liked my Stagg but I love the SLB 200, it works for me. Quote Link to comment Share on other sites More sharing options...
zvirus Posted June 1, 2019 Share Posted June 1, 2019 (edited) 1 hour ago, Staggering on said: The Stagg I owned and the Yamaha SLB200 that I use now both have a power switch in the output jack and some owners are not aware of this and wonder why their batteries don't last. If the cable is plugged in the preamp is on. ... Very good point. I was aware of it long time ago... before went to passive basses. Can`t afford "proper" DB so must use stagg and its active electronic.... Just for a bit of info. Before the mod after about week of playing I guess 2-3h in total battery voltage dropped about 1V - In a week WITHOUT jack inserted into Stagg`s output. So 20mA draw from factory is A LOT I`d say... SLB 200.... say nothing... wish I could afford... Cheers! Edited June 1, 2019 by zvirus Quote Link to comment Share on other sites More sharing options...
Staggering on Posted June 1, 2019 Share Posted June 1, 2019 10 minutes ago, zvirus said: Just for a bit of info. Before the mod after about week of playing I guess 2-3h in total battery voltage dropped about 1V - In a week WITHOUT jack inserted into Stagg`s output. That is pretty strange, a lot of drop with the jack out. I didn't keep track of my batteries on a regular basis when I had the Stagg but did check them before each gig and replaced them if they had dropped much but I can't remember the details.The batteries lasted quite a while before they started to die and the EUB got quieter and quieter and finally quit, I wish I had checked the voltage at that point to see exactly where it quit working. I actually used the Stagg a lot, it was my first foray into the upright world and sounded good in my jazz quartet but when an SLB appeared with an unbelievably low price I just had to buy it and although some people don't like them it is perfect for me. BTW, I went even farther down the slippery slope last year when I visited England ( I'm Canadian ) and went to the double bass bash in April.That experience produced serious GAS and last June I bought a DB and use it on most gigs but use the SLB for rehearsals and gigs in venues with limited space. Be careful, upright is addictive, but so much fun! 😉😊 Quote Link to comment Share on other sites More sharing options...
zvirus Posted June 1, 2019 Share Posted June 1, 2019 1 hour ago, Staggering on said: .. Be careful, upright is addictive, but so much fun! 😉😊 Well well I was scared to move on Electric DB but now I prefer to play (actually learn) on EDB than play electric bass so looks its too late.... I`m already collecting money for DB(!) After Stagg`s arrival wife said: " I was thinking you are getting Double bass not some sort of ugly stick! 🙄 " NOTHING is better than a sound of a Double Bass - NOTHING.... I play fretless too and still insist DB sounds more "woody".... Quote That is pretty strange, a lot of drop with the jack out. I didn't keep track of my batteries on a regular basis when I had the Stagg but did check them before each gig and replaced them if they had dropped much but I can't remember the details. For one person it will be nothing for another plenty.... I do not care as my stagg draws only 7mA.... and I`m a far away from gigging yet Cheers! Quote Link to comment Share on other sites More sharing options...
Staggering on Posted June 1, 2019 Share Posted June 1, 2019 Well your wife has the right idea and you are very lucky that way.Go for it!😉 Not particularly good pics but this is me with the Stagg I had and my Engelhardt Swingmaster ES9, not a very well regarded bass by some, but it looks great and sounds good for the music I play. 2 Quote Link to comment Share on other sites More sharing options...
zvirus Posted June 2, 2019 Share Posted June 2, 2019 11 hours ago, Staggering on said: Well your wife has the right idea and you are very lucky that way.Go for it!😉 Not particularly good pics but this is me with the Stagg I had and my Engelhardt Swingmaster ES9, not a very well regarded bass by some, but it looks great and sounds good for the music I play. This photo explains your Avatar.... great studio and good looking DB too... Quote Link to comment Share on other sites More sharing options...
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