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Topic: DiY Buffer |
Dave Hepworth
From: West Yorkshire, UK
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Posted 12 May 2016 1:38 am
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Hi folks ,
I have just built this buffer unit from scratch ,not a kit. It works absolutely great too.Anyone else done this sort of thing?
Regards Dave
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Robert Parent
From: Gillette, WY
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Posted 12 May 2016 3:28 am
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Yes, I have used similar DIY buffers for decades.
Robert |
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Dustin Kleingartner
From: Saint Paul MN, USA
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Posted 12 May 2016 6:11 am
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I have been thinking about trying to make something like this lately. Glad to hear it works well. _________________ Proud parent of a good dog. |
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Craig Baker
From: Eatonton, Georgia, USA - R.I.P.
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Posted 12 May 2016 6:42 am
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Dave,
Congratulations, you have discovered the secret of success.
While everyone knows that black steel guitars sound better, for a buffer to work well, it must be in a blue case.
All the best,
Craig _________________ "Make America Great Again". . . The Only Country With Dream After Its Name. |
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ajm
From: Los Angeles
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Posted 12 May 2016 7:20 am
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Good job. If it works, it'll probably last forever. But just being picky (because we can), and for any others who may be thinking about doing something similar......
1) I'd add a reverse biased diode from V+ to ground to protect the circuit.
2) I'd add a filter cap from V+ to ground. It doesn't need to be huge. Anywhere from 1uF to 10uF is plenty.
3) I'd use a socket for the op amp.
4) There are project boards that are a little bigger than yours that have rows of common connections on them. It makes putting things together a little easier, especially if you end up using a few more parts than yours has.
5) If you get a large pop or thump when you plug/unplug it, you might try adding a large value resistor from the "-" side of the output cap to ground. Try 1Meg for starters.
There are several companies out there that make kits. Build Your Own Clone and General Guitar Gadgets are two that come to mind. BYOC in particular are very good IMO.
These web sites as well as many others also show you the schematics. If you find a design you like, but for some reason don't want to buy the kit, you can get the parts and "roll your own". |
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Dave Hepworth
From: West Yorkshire, UK
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Posted 12 May 2016 9:41 am
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Hi Craig and ajm,
Thankyou both for the positive comments.I might consider the antipop resistor across output cap.
The idiot diode I think I will leave as the battery slot is polarised and only goes in one way and the battery tray is clearly labelled too.
I will review the filter cap as I go along at gigs.
Blue has always been my favourite colour Craig and if make any project it is always sprayed blue ,maybe something in it !
Regards Dave |
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Steven Paris
From: Los Angeles
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Posted 12 May 2016 9:55 am
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I would totally agree with ajm's suggestions; I would only add that, if doing it yourself, there HAS to be a better choice for an opamp than a 741 or a TL071. An OPA 134 would be a pretty good choice. _________________ Emmons & Peavey |
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John Sluszny
From: Brussels, Belgium
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Posted 12 May 2016 10:01 am
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Excuse me but as I am not very electronically oriented,what is it for ? Thanks ! |
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Lane Gray
From: Topeka, KS
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Posted 12 May 2016 2:13 pm
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Cables <strike>can</strike> will bleed highs of a high impedance signal off to ground. Passive volume pedals can do this too (this effect is called "tone suck").
Pickups are high impedance devices.
The buffer converts the impedance to a low Z signal.
The end result is often called "cleaner."
Not all buffers are equal, some sound better than others.
Some people don't like the buffered sound as much.
Remember that Hendrix actually PREFERRED the sound of a 20 foot cable.
They're a net good, usually. _________________ 2 pedal steels, a lapStrat, and an 8-string Dobro (and 3 ukes)
More amps than guitars, and not many effects |
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John Sluszny
From: Brussels, Belgium
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Posted 12 May 2016 2:57 pm
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Thank you Lane ! If only we could hear a "with and without"test of it ! |
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John Groover McDuffie
From: LA California, USA
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Posted 12 May 2016 3:59 pm
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Not to mention the fact that the cables of that era had way worse capacitance than modern cables, and therefore the 20ft cables Hendrix used would have degraded the signal a lot more than modern cables would have.
But playing a Strat through a cranked Marshall the high-end roll-off was probably a benefit. |
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Frank James Pracher
From: Michigan, USA
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Posted 13 May 2016 7:43 pm
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I've never made a stand alone buffer, but I build my own effects all the time. Delay, Reverb, Tremolo, etc.
I started tinkering with electronics at the same time I began playing music, so the two have always gone hand in hand. _________________ "Don't be mad honey, but I bought another one" |
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Lane Gray
From: Topeka, KS
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Nathan Guilford
From: Oklahoma City
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Posted 14 May 2016 3:42 am diy buffer
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I built one using the same schematic that you have and it's a great buffer. I used the TL071 chip as well. It's just fine. I don't notice noise and I added a switch to disengage the battery so it can stay hooked up in my rehearsal space without the battery going dead. I don't know why, but it seems to have a bit of a boost into my amp which I like.
I also have a Lil Izzy buffer. A fantastic buffer that accomplishes a crispy high end that my diy buffer doesn't get.
I use both almost interchangeably and really only notice the differences when I switch between them. However without a buffer plugged directly into my guitar, I really really notice a drop off of high end tone, and I don't like to play without one.
My two cents. Maybe that's just my guitar and rig, but I'd say I'm extremely happy with either. _________________ '02 Carter S-12 uni
‘76 MSA D-12
www.toothbrushers.com |
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Dave Hepworth
From: West Yorkshire, UK
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Posted 14 May 2016 6:51 am
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Hi Nathan,
Nice to hear from someone who has done the same.I think the extra top end crispness can be achieved by altering the value of the output cap to a smaller value .......perhaps someone more knowledgeable about the buffer circuit could chip in here .......pun intended !! Lol.
Regards Dave |
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John Sluszny
From: Brussels, Belgium
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Posted 14 May 2016 10:39 pm
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Thank you Lane ! |
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Georg Sørtun
From: Mandal, Agder, Norway
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Posted 15 May 2016 9:54 am
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Dave Hepworth wrote: |
I think the extra top end crispness can be achieved by altering the value of the output cap to a smaller value .......perhaps someone more knowledgeable about the buffer circuit could chip in here .......pun intended !! Lol. |
Smaller value for the output capacitor will not make the buffer sound "crispier", it will only make the highpass filter that capacitor forms start to roll off the lows at a higher frequency. I don't think that is what you want.
I do sometimes put a 10nF, high quality, non-polarized capacitor in parallel with the electrolytic capacitor on the output, but that's just to make such a circuit more linear for higher audio-frequencies - electrolytic capacitors are not the best full-frequency components. This still won't do much to make it sound "crispy" though, it will just be a little more phase-linear up high.
Boosting the high audio frequencies in the 2 to 10KHz range a few decibel, will make it sound more "crispy". That is easiest done by modifying the negative-feedback loop so the circuit amplifies a little more than unity over the entire audio-range, and a little extra in the "harmonics" range...
...and goes down to unity again above audible frequencies to minimize sensitivity to HF noise.
I don't know what would be the right degree of boost, or non-linearity, to make it sound "just right" compared to other buffers, so I haven't included any component-values. I just sketched out the simplest solution I could think of based on what you've already got. |
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John Gould
From: Houston, TX Now in Cleveland TX
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Posted 15 May 2016 4:42 pm Buffer's
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I've been building buffers for a while now. I can tell you not all buffers are created equal. The op-amp buffer you built is one of the easiest to build and should give okay results . JFET buffers sound a little different and then you can build a transistor buffer as well . the notion that you are not asking for gain from any of the devices leads people to think that the results will be the same. Each one of those devices has its on character , I know my ears like a tiny bit of harmonic distortion , seems to sound more real and less sterile . Anyway have fun , I have fun tinkering with mods and building little audio projects to improve my signal path. _________________ A couple of guitars
Fender GTX 100 Fender Mustang III Fender Blues Jr. Boss Katana MKII 50
Justice Pro Lite and Sho Bud Pro II |
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Dave Hepworth
From: West Yorkshire, UK
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Posted 16 May 2016 1:30 am
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Hi
Thankyou for the schematic Georg ,some values would be nice if you have any,I can see the feedback loop there and see how it will enhance the upper tones.
To John,have you any schematics with values.These things are so cheap to build .......the project box is the most expensive item.
I am quite smitten now with these devices and am ready to have a go at another.
Regards Dave |
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Nathan Guilford
From: Oklahoma City
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Posted 16 May 2016 8:19 pm Harmonic distortion
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John - I'm curious. Which type of buffer do you feel provides the harmonic distortion that is pleasing?[/quote] _________________ '02 Carter S-12 uni
‘76 MSA D-12
www.toothbrushers.com |
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ajm
From: Los Angeles
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Posted 17 May 2016 6:59 am
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Here is an example of the project board that I was talking about. It makes things much easier to wire up. If you don't need the whole board you can cut it to size.
Even though Radio Shack is no longer in business (even though there is one open near me), you can find similar items out there.
https://www.radioshack.com/products/multipurpose-pc-board?variant=5717554117 |
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Scott Duckworth
From: Etowah, TN Western Foothills of the Smokies
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Posted 17 May 2016 7:38 am
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Here's an original drawing of the buffer mention in the start of the thread...
_________________ Amateur Radio Operator NA4IT (Extra)
http://www.qsl.net/na4it
I may, in fact, be nuts. However, I am screwed onto the right bolt... Jesus! |
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Craig Baker
From: Eatonton, Georgia, USA - R.I.P.
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Posted 18 May 2016 12:27 pm
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Dave,
As Georg mentioned, electrolytic capacitors may not be the best choice for audio circuits. For your output, 10 mfd is really overkill. As long as you're driving a high impedance load, you could probably get by using a 2.2 mfd and retain full frequency response. One thing you might want to try in order to gain an apparently "cleaner" sound would be to use tantalum capacitors. They are a bit more expensive, but some "experts" claim they can hear a difference when using tantalum caps.
Best wishes as you chase the perfect tone. . . we're all doing that. Let us know what you discover.
Respectfully,
Craig Baker 706-485-8792
cmbakerelectronics@gmail.com
C.M. Baker Electronics
P.O. Box 3965
Eatonton, GA 31024 _________________ "Make America Great Again". . . The Only Country With Dream After Its Name. |
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Steven Paris
From: Los Angeles
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Posted 18 May 2016 12:59 pm
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Then again, some experts HATE tantalum capacitors. This is a quote from DIY audio guru Rod Elliott:
"Then of course we have tantalum electrolytics. While many sing their praises, I do not recommend their use for anything, other than tossing in the (rubbish) bin. There might be the odd occasion where you really need the properties of tantalum based caps, but such needs should be few and far between. They are unreliable, and have a nasty habit of failing short-circuit. They cannot tolerate high impulse currents and/or rapid charge/ discharge cycles, and especially don't like being shorted. Tantalum caps announce their failure by becoming short-circuited, and it can be extremely difficult to track down a (possibly intermittent) short across a supply bus that powers many ICs. I never use tantalum caps, and don't recommend them in any of the published projects. Personally, I suggest that you don't use them either."
This is from: http://sound.westhost.com/articles/capacitors.htm#s25 _________________ Emmons & Peavey |
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Craig Baker
From: Eatonton, Georgia, USA - R.I.P.
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Posted 18 May 2016 1:53 pm
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Steven,
I'm beginning to get the impression that Rod Elliott doesn't like tantalum capacitors.
Thank goodness Tommy White and Gary Carter like them. By the way, Ron Elliott likes them too.
For some reason the major high-end audio equipment manufacturers forgot to check with Rod. Go figure.
Respectfully,
Craig Baker 706-485-8792
cmbakerelectronics@gmail.com
C.M. Baker Electronics
P.O. Box 3965
Eatonton, GA 31024 _________________ "Make America Great Again". . . The Only Country With Dream After Its Name. |
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