Buffered inputs.

[Helmholtz]

THAT^^^^^^^^^^^^^^^^^^

I think the best, common uses for an in line buffer are

1) In old school recording. Where you have a room with a guy and an instrument and the amp in an iso cab or some other room. It allows the musician to use the same cable length tone they normally would regardless of how much cable is added after the buffer. And other similar situations in a studio where cable length can get out of hand quickly.

2) When you happen to be playing a large stage or venue that requires a lot of cable. The buffer goes from the floor effects board.

But notice that in both of the above cases the buffer is used after a length of cable. If the buffer were used at the guitar or on a belt or strap the sometimes desirable interaction between passive pickups and cable capacitance can't occur.

I don't know what cables you're using but is sounds like your desired level of interaction is ten feet of THAT cable. If you'd like even less interaction you'll need to go with the preamp in the guitar or the belt/strap mounted unit like Juan mentioned.

Does anyone still use wireless systems? I never have, but I would think there would be some buffering advantage there. Hopefully tune-able for a desired pickup/capacitor reactance.?.

You did not mention the situation where one or more pedals with True Bypass are used. A buffer before these pedals eliminates the resonance shifting effects of the additional capacitances of the cables between the pedals and from the last pedal to the amp. I always use a buffer or buffered pedal first in the chain to avoid changes in sound character with effects on or off.

[catalin gramada]

Unfortunately my TC Bonafide buffer cannot be feed it from battery to be beared onto guitar belt. It draws too much current for a regular pile. 40mA arround declared in tech. specs. Does anyone have a schematic,please? I wonder how much can save if I disaffect the bypass circuit which use a internal relay?

[R.G.]

I've thought about buffers several times over the years. The company I work for manufactures a micro-pedal type buffer that is just that - a buffer, no controls or switching. It's not fancy, but it does a great job of doing, as mentioned above, just turning a high impedance signal into a low-impedance, treble-saving low impedance one with no other manipulations of the signal. This design, trivial as it was, led though a slew of thinking about buffers by the guys in the office that tested it and offered their opinions. Not all the opinions were kind or subtle.

As noted above, buffering can be considered a stopping point for any considerations of what anything later in the signal chain is doing inadvertently to the signal. Cable capacitance ceases to be an issue after the buffer, as noted above, and as forcefully ... um ... mentioned to me by the real tone hound in the office. He took a while to convince.

From the technical perspective, buffering ought to be done as close to the signal source as possible - in the guitar. That raises the obvious question of how we as guitarists have come to like the high frequency rolloff of the pickup/controls/cable system. And that's fairly easy to fake in most cases - use a capacitor/resistor load in the guitar before the buffer to fake the cable loading. This isn't a perfect re-creation of the distributed impedance of a cable, but it's generally good enough for audio.

So one option is to buffer right after the pickups. This has the problem that guitar controls have evolved to match the pickups' internal impedance, and are themselves high impedance, and have a loading effect and response to the cable capacitance and amplifier load themselves. So buffering might better be done at the output jack of the guitar.

This offers the option that you could cut the audio wires from guitar controls to guitar jack, insert a cable-faking load and a buffer at the pickup side, and then connect the buffer to the jack.

That offers the option of customizing the "cable loading" to anything you like, irrespective of the actual cable, which might be nice in and of itself. Having said that virtually out loud, I suspect someone will offer a "Jimi Hendrix Coily Cord" adapter along these lines.

Having done this, you face the issues of how to make a buffered signal work right with Fuzz Face clones and the few other pedals where signal impedance is a defining factor in the pedal sound. Fortunately, that can be solved by the expedient of putting some lumped impedance back in series with the low-impedance signal. This can take the form of a resistor for quick and dirty fixing, or an inductor-capacitor filter to restore some semblance of the actual pickups/controls impedance.

[bbsailor]

Buffering a passive guitar pickup, as close to the guitar output as possible, eliminates/minimizes cable capacitance and additional amp input impedance loading. The Schatten Design Mini Pre uses a single 9V battery that lasts 1500 hours of use. It has a 10M ohm input impedance and a 3.5K ohm output impedance. If anyone wants to hear what your guitar would sound like without the additional loading of amp input of 1M ohm and 30 pf of capacitance per foot of guitar cable just get a short cable (1 foot) to connect your guitar to the Mini Pre and then connect the Mini Pre to your amp with any length guitar cable and it will sound brighter for these reasons.

The pot value load for a 500K Pot in parallel with a 1M ohm amp input is about 333K as seen by the pickup. For a 250K pot in parallel with a 1M ohm amplifier input impedance it is about 200K ohms as seen by the pickup. This reduced load will give the resonance point a little higher Q value and make the resonant peak voltage a little higher.

The reduction of capacitance, as seen by the pickup will be about 300 pf less (not counting the capacitance of the short jumper wire from the guitar to the Mini Pre) which will raise the resonant frequency of the pickup which is governed by the induction value of the pickup coil plus the inter-winding capacitance of the coil plus the guitar cable capacitance.

Guitar pickups evolved to wind enough wire around the magnets to get a high enough signal level to drive very early tube based input stages. The consequences of this design have created the classic "Electric Guitar Sound" that has been made popular and memorable from the evolution of Rock n Roll and other popular music styles by popular performers such as Eric Clapton's "woman tone".

Removing the added load makes the pickup brighter but by simply switching back into the circuit the equivalent resistance loading and capacitance or adjusting the passive tone control will allow the older, non-buffered sound to be had again.

Web search on this: "Tillman Buffer" for a circuit where an FET buffering transistor is mounted in the guitar cable on the plug end that attached directly to the guitar output. Power is fed from the amp end of the cable so battery life is not an issue. I made one of these and every guitar that I used this with passive pickups sounded brighter and I could definitely hear the direct effects of additional pot loading and cable capacitance with no mods needing to be made to any guitar I tried it on.

A quick try of using the Mini Pre available from Stewmac.com for about $65.00 will tell you if you like the buffered sound and then build a Tillman buffer and you can expand the tonal range of you guitar collection with no mods.

If anyone wants to dive deeper into this, then put a Tillman JFET buffer directly inside your guitar after the pickup output but before the pot volume controls. By isolating the pickup from the output loading of the pot values, amp input impedance loading and cable capacitance you will hear a wider range of guitar sounds but only need to worry about keeping spare 9V batteries on hand. With this setup you can run long 20 to 30 foot guitar cables with no noticeable loss of high frequencies.

I hope this helps?

Joseph J. Rogowski

[Chuck H]

I've thought about buffers several times over the years. The company I work for manufactures a micro-pedal type buffer that is just that - a buffer, no controls or switching. It's not fancy, but it does a great job of doing, as mentioned above, just turning a high impedance signal into a low-impedance, treble-saving low impedance one with no other manipulations of the signal. This design, trivial as it was, led though a slew of thinking about buffers by the guys in the office that tested it and offered their opinions. Not all the opinions were kind or subtle.

As noted above, buffering can be considered a stopping point for any considerations of what anything later in the signal chain is doing inadvertently to the signal. Cable capacitance ceases to be an issue after the buffer, as noted above, and as forcefully ... um ... mentioned to me by the real tone hound in the office. He took a while to convince.

From the technical perspective, buffering ought to be done as close to the signal source as possible - in the guitar. That raises the obvious question of how we as guitarists have come to like the high frequency rolloff of the pickup/controls/cable system. And that's fairly easy to fake in most cases - use a capacitor/resistor load in the guitar before the buffer to fake the cable loading. This isn't a perfect re-creation of the distributed impedance of a cable, but it's generally good enough for audio.

So one option is to buffer right after the pickups. This has the problem that guitar controls have evolved to match the pickups' internal impedance, and are themselves high impedance, and have a loading effect and response to the cable capacitance and amplifier load themselves. So buffering might better be done at the output jack of the guitar.

This offers the option that you could cut the audio wires from guitar controls to guitar jack, insert a cable-faking load and a buffer at the pickup side, and then connect the buffer to the jack.

That offers the option of customizing the "cable loading" to anything you like, irrespective of the actual cable, which might be nice in and of itself. Having said that virtually out loud, I suspect someone will offer a "Jimi Hendrix Coily Cord" adapter along these lines.

Having done this, you face the issues of how to make a buffered signal work right with Fuzz Face clones and the few other pedals where signal impedance is a defining factor in the pedal sound. Fortunately, that can be solved by the expedient of putting some lumped impedance back in series with the low-impedance signal. This can take the form of a resistor for quick and dirty fixing, or an inductor-capacitor filter to restore some semblance of the actual pickups/controls impedance.

Or we could just wait around for decade and then use the easy bake USB output on our guitars plugged straight into a digital interface that spoon feeds us all the solutions in ready made tones that "sounds exactly like Jimi through a coily cord into a Fuzz Face" All conveniently reproduced by the computer monitors with the right simulated impedance response curves and EQ to sound "just like a plexi Marshall through a 4x12 cabinet with green back Celestions."

"Order yours now for $49.99. Use *mazon Prime and save 10%"

I guess my point is it's probable that this as close as the future will get to our efforts regarding things like this. I have trouble imagining the most recent generation of guitar players fussing about how to make 1990 technology sound like 1970 technology when 2030 technology already simulates any era and it's gear. But here we are in 2018 with analog ears and sensibilities. Likely making some of the best sounding amps, pedals, buffered interconnects, cables and such that will ever be. Meanwhile little 15yo Billy, with his Bob Marley T-shirt and his Line 6 amp wouldn't know what to do with a 100W Marshall turned up past ONE and never will.

So are we just dinosaurs wasting our time and effort?

I think the nature of this thread, with on board guitar preamps, in line buffers and other tech born in an era that was new before whats now coveted was old, just has my gears grinding. I don't imagine the Peavey TNT amps will ever be sold as amps from a golden era of tone.?. It's all just a little weird.

Rant over.

[Enzo]

My solution for long cords is a wireless. Cord is a foot or so in length. receiver sits on the amp. Want pedals? Short cord from axe to pedals and plug the belt pack into the last pedal on the board.

[Chuck H]

That way you can play without all the muck-y muck.

[galaxiex]

My solution for long cords is a wireless. Cord is a foot or so in length. receiver sits on the amp. Want pedals? Short cord from axe to pedals and plug the belt pack into the last pedal on the board.

I used to have a Samson wireless.
The Rx was a tiny pedal sized thing and the Tx a little bug that plugged right into the guitar jack.

Put the Rx as first (obviously) on the pedal board, and a cable to the amp after the string of pedals.

So I was wireless to the P/B but still had a 10 (or 20 ft depending) cable to the amp.
That cable was driven by the last pedal in the chain, so probably low impedance.

Worked ok, but the Rx blew up when I accidentally plugged in wrong polarity...

Now I'm all wired again...

[J M Fahey]

Unfortunately my TC Bonafide buffer cannot be feed it from battery to be beared onto guitar belt. It draws too much current for a regular pile. 40mA arround declared in tech. specs. Does anyone have a schematic,please? I wonder how much can save if I disaffect the bypass circuit which use a internal relay?

Any relay eats too much for battery use.

But please build a *simple* unity gain buffer on a piece of perfboard and try it, for the experiment you don´t even need a case.



A TL061 eats only 250uA so a 9V alkaline lasts 2000 hours at least

[olddawg]

I almost always use a wireless. Modern ones are very transparent. It isolates you from ground issues. Makes guitar changes easier. Makes less clutter on the stage. It's a buffer and can also add a little gain if you want. And I get to walk around the room if you like. On breaks I just mute my TU2 and unplug whatever guitar I'm using.

[Chuck H]

olddawg said: "Bluh, bluh, bla, bla....

It isolates you from ground issues

... bla, bluh, bluh, bla."

I know this threads topic is about the buffering but anyone who's ever taken a hit on stage will recognize this as the biggest advantage.

[olddawg]

olddawg said: "Bluh, bluh, bla, bla....... bla, bluh, bluh, bla."

I know this threads topic is about the buffering but anyone who's ever taken a hit on stage will recognize this as the biggest advantage.

Hell yes.. especially since you can never trust an outlet to be grounded no matter how new the receptacle. Nothing like the "Blue flash of death"... Stone the Crows!

[galaxiex]

I almost always use a wireless. Modern ones are very transparent. It isolates you from ground issues. Makes guitar changes easier. Makes less clutter on the stage. It's a buffer and can also add a little gain if you want. And I get to walk around the room if you like. On breaks I just mute my TU2 and unplug whatever guitar I'm using.

What wireless are you using?

I'm looking for ideas... thinking I'd like to go wireless again.

The Samson I had was (I thought) kinda expensive at ~ $300.00 I know Pro systems are much more than that...

Hoping to find something decent for $250.00 or less.

I don't need "Pro" quality, just do occasional casual gigs,
but it's fun to walk around and go out front and hear the house mix.

[The Dude]

I have a Sennheiser. Expensive, but worth every nickel. I'm sure there are others that are just fine. Just a couple of things. If you buy one used, make sure it's legal. The FCC recently blocked many bands for wireless devices.

https://www.fcc.gov/consumers/guides...ss-microphones

There's a chart of legal/illegal frequencies on the web somewhere, but I can't find it at the moment.

I can also suggest NOT buying any Line 6 wireless devices. I tried several and they cut out constantly.

[galaxiex]

I have a Sennheiser. Expensive, but worth every nickel. I'm sure there are others that are just fine. Just a couple of things. If you buy one used, make sure it's legal. The FCC recently blocked many bands for wireless devices.

https://www.fcc.gov/consumers/guides...ss-microphones

There's a chart of legal/illegal frequencies on the web somewhere, but I can't find it at the moment.

I can also suggest NOT buying any Line 6 wireless devices. I tried several and they cut out constantly.

Good to know, Thanks!