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Post by blademaster2 on Mar 5, 2019 11:42:56 GMT -5
So, per my recent post on this topic, would you agree that it seems unlikely that Brian May's Burns TriSonic Pickups on his Red Special could actually work well enough as a microphone for Brian to talk back through them to the studio control room?
This was depicted in the movie Bohemian Rhapsody when they were in the studio recording Brian for that song.
I feel that if those pickups were truly that responsive to his voice it would make them almost useless on his guitar.
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Post by blademaster2 on Feb 12, 2019 17:49:43 GMT -5
I still believe that Brian May's pups should not be microphonic enough to permit him to speak to the control room through them.
But I cannot say for sure, so I will have to throw in the towel on this and concede that it was not purely make believe.
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Post by blademaster2 on Feb 12, 2019 9:40:51 GMT -5
Since my post I have seen anecdotes on line of performances when the guitar player screamed into the pups and the audience could hear it, but I sincerely doubt these could be used as the microphone the way BoRhap showed it (and I would also expect that they would be terrible pups if they did work that way).
It surprised me that Brian May, who was consulted in some way for the film, did not gently suggest that they refrain from something so inaccurate.
In my online search I saw a post on a forum claiming that guitar pups *must* be microphonic to pick up the harmonics of the strings, otherwise all guitars would sound the same. I still get surprised by the claims I see on other forums.
And yeah, Gravity. Absolutely no regard for accuracy, plausibility or orbital mechanics .... but Sandra Bullock looked great.
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Post by blademaster2 on Feb 11, 2019 11:55:27 GMT -5
I saw Bohemian Rhapsody and was surprised that they depicted Brian May speaking directly into the guitar pickups so that the others in the control room portion of the studio could hear him.
I thought this was rather silly - guitar pups might have some microphonics, but these are non-ideal and May - like many - potted his Burn Tr-Sonic pups himself specifically to *reduce* microphonics. Moreover, if there was a mic on the guitar amplifier in the room he would probably have been better heard by directing his voice in that direction.
Do any others in the forum have any experience in trying this to say for sure that this was simply Hollywood silliness (as I thought), or am I simply missing something fundamental here?
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Post by blademaster2 on Feb 4, 2019 17:25:03 GMT -5
So now I am curious. The addition of metal covers onto pickups has a measurable (and definitely audible) impact, as I observed myself in 2018.
When shielding is added it is not significantly thicker than the covers - at least some of the shielding I have seen. True, it is thicker but I am guessing less than an order of magnitude.
So what governs the apparently negligible effect of shielding in such close proximity to the pickup, whereas the covers (and a Tele steel bridge as I understand it, but I do not have a Tele) create a non-negligible difference?
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Post by blademaster2 on Jan 15, 2019 11:19:50 GMT -5
Agreed, ReTrEaD. For that length and gauge change I would expect to hear the difference myself
One of my regrettable experiences in detecting subtle differences came when I expected no difference at all: My first solid body guitar, built from soft but resonant mahogany, sounded amazing. It was rich but with bite, and would feedback notes like a cello. I assumed that this was only because of the pickups (DiMarzio Dual Sound), and since I had not been pleased with my polyurethane finish I dismantled the guitar and sent the body off to a (not very skilled) guy to refinish it with lacquer so it would look more professional.
He applied a thick lacquer coat, just as I had requested. It had a much better looking surface (after I polished it myself).
When I reassembled the guitar I did not at first notice any change, but eventually I recalled that the richness of the tone I used to hear and (most notably) its ability to feedback notes was substantially reduced. It still sounded good, but it required much higher volumes on the same amplifier to feedback those same notes (actually, fewer notes would respond like that) in the same room at the same distance. It also seemed to sound less warm overall. I believe the new finish penetrated deeper into the wood and stiffened it up, thereby changing its acoustic properties.
All of this was very subtle, mostly based on impressions except for the elevated volume setting on the amplifier needed for feedback. I doubt I would have detected it with a blindfolded test. The difference was totally unexpected and certainly not a product of bias - except that my initial bias was to expect no difference at all.
If I could "undo" that refinish job I definitely would.
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Post by blademaster2 on Jan 15, 2019 9:55:13 GMT -5
Sumgai,
No question many claims are far fetched and do not seem to have a shred of technical plausibility. Many A/B comparisons lack the rigor of a true A/B for practical reasons. Then there are the human senses that are admittedly fraught with bias, change from day to day, and are extremely difficult to control even if no agenda is at play.
For many things the differences are too subtle for anyone - even the most bias-free - to nail down consistently. I would say that about guitar tone and audio systems (and fine wine/scotch, frankly). Specifically for me and the guitar, the differences are often so tactile and feedback-driven that I would not detect it if I am not playing it myself at that moment, making an A/B comparison even more difficult. I have recordings from years ago where I know I used one of my guitars but cannot recall which one. I cannot say from the tone that I hear which guitar it is, and yet the differences are definitely there when I play them.
On that note, I cannot usually tell if a guitar player is playing a particular guitar or quality of guitar on a recording (I can *usually* tell a humbucker from a single coil, especially if totally clean, but even then I am sure I could be fooled depending on the attack and playing style). For an acoustic, I doubt I could hear from someone else's playing what I sense myself when playing a "good" one versus a cheap one (which makes your blindfolded A/B test far more difficult). No one seems to notice that Tom Sholz played the intro to "More Than A Feeling" on a $100 Yamaha 12-string after he was not able to get the feel he wanted when trying to re-record it with the more expensive Taylor guitar he was given after they signed their record deal.
The differences in many of these cases might be akin to comparisons of Gaussian-distributed parameters that require a T test to determine if a statistical difference really exists. We are all splitting hairs in these types of debates and any single "result", or lack of result, will never fully convince me. 50% consistent you say? Certainly not for my senses.
Having said that, I will definitely not be spending money on fuses that are supposed to improve the sound of my stereo, nor on oxygen-free cables in my studio set up.
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Post by blademaster2 on Jan 14, 2019 16:15:42 GMT -5
This product line .... www.airestech.com/Hmmmm. This seems more like snake oil than any audio product offering I have seen.
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Post by blademaster2 on Jan 14, 2019 16:12:59 GMT -5
.. and the products on that website must be a joke, right?
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Post by blademaster2 on Jan 14, 2019 16:10:04 GMT -5
.... but yes, those fuses do seem like fiction to me, too.
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Post by blademaster2 on Jan 14, 2019 15:59:20 GMT -5
I am quite sure that I would never hear the difference with different fuses or fuse technologies, and similarly I would never expect to hear the difference between enormous monster cables for power or for speakers.
I would not, however, be dismissive of others' opinions and claims.
Yes, there are placebo effects and the technology-illiterate are targets for salesmanship and the aforementioned snake oil. As I see it there *likely* is little or no difference to be heard and I would not spend the money - however I cannot say with certainty that there is no difference heard by other people. Power supply impedance and current step response could affect sound quality, a fuse is part of that chain (and by definition introduces a higher resistance into it), and the system's power supply capacitors also have their own ESR and inductance non-idealities, so who is to say?
I *do* know that the use of oscilloscopes and spectrum analyzers will not permit us to see the subtleties that we all hear with our own senses (just try and identify the differences between the oscilloscope traces of various plucked string instruments, or a cheap toy acoustic guitar versus a Taylor ...), so folks who point to those types of measurement results and claim that there is no difference to be heard are - in my opinion - being overly simplistic and not really looking at the true comparison.
Just like comparing a fine wine or single malt scotch, I would need to determine from my own senses/hearing what I wanted to buy and no one can convince me that I do, or do not, hear what I hear.
But in a truck, yeah I would avoid a high-priced solution as well.
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Post by blademaster2 on Jan 9, 2019 13:49:58 GMT -5
Yes, agreed for sure.
I would never use a capacitor to support that wiring in mid-air. I would suggest that you totally discard #3, as I cannot see any benefit for it that outweighs the increased risks.
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Post by blademaster2 on Jan 9, 2019 12:46:13 GMT -5
One more thing: the ground connection should be routed without forming a ground loop, although this is sometimes trick to achieve in practice for actual wiring.
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Post by blademaster2 on Jan 9, 2019 12:43:07 GMT -5
From what I see there they are the same (the first two are exactly the same but only relocates the connections, and the third one swaps the location of the cap and the pot but since they are in the same series circuit it makes no difference).
The differences seem to be based on convenience as to where you want to put things physically for ease of soldering and assembly and wire routing, but I see no other differences (unless I missed something in my rather quick look I had at them).
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Post by blademaster2 on Dec 10, 2018 10:37:02 GMT -5
Just a thought:
Except for power supply smoothing via the added cap, does your circuit creates its rails by splitting the DC supply locally and considering the mid-point to be 'ground' (I am not looking at the circuit just now so I apologize if this is obvious on inspection)?
If so, then a ground-referenced adapter might not be happy with this circuit if it plugs into a grounded amplifier, since it will short out the bottom half of the split supply that was created from an already-grounded adapter.
Besides that, and power supply smoothing form the adapter I cannot imagine anything else that would be different.
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Post by blademaster2 on Nov 29, 2018 13:10:33 GMT -5
Interesting!
My son went to a Steven Wilson concert in Toronto on 27 November (this past Tuesday) and Wilson told the audience that he was going to tell a guitar joke (many of the audience were likely under 25 years of age).
He held up his vintage Telecaster and said: "To those of you who are younger than 25 - this is called a guitar!"
Ironic that this was on National Electric Guitar Day, no?
Perhaps the trend for rap, hip hop, and other similar cheap-to-produce music will start to give way to music that once again involves developed skills and musical knowledge, like the music by my favourite instrument, the (electric) guitar. I have seen it wane in the past, only to return with renewed vigor. I hope this happens again.
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Post by blademaster2 on Nov 28, 2018 9:50:43 GMT -5
Wow - good luck with that!
I have never had much success with those white breadboards (I started to think I was simply not able to design anything that would work), but I started getting a far better success rate when I started soldering up my circuits.
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Post by blademaster2 on Nov 16, 2018 10:15:16 GMT -5
Much respect indeed for Mr. Clark. His talent was amazing. From any interviews I saw of him as a kid he seemed to be a genuinely nice person, and quite modest.
I always felt he was under-appreciated as a musician, possibly because of the light-hearted Hee Haw image. It would have been great to see him get the recognition he seemed to deserve (but it was possibly before my time enough that he did get it and I was not aware of it). I would have liked to see him branch out into other styles, and to see him live.
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Post by blademaster2 on Nov 13, 2018 10:56:15 GMT -5
fugly wiring and enclosure job, but i turned a regulated 19v laptop power supply into a power supply for a pedal board. 9v (welllll it's an lm7810 to give that fresh 9v battery sound) and 12v (let's see what some more headroom can do) fun little project! I was wondering how this laptop worked out for you. Did you get the 9V (10V?) and 12V outputs smooth enough so that no switching supply noise came through? I gather it switches at fundamental frequencies high enough that it is above audio anyway, but I wondered if that could modulate down into the audio range. If not then I like this as a way to salvage stuff like that for pedal use. Computer hardware is so much more frequently scrapped than guitar gear (where the vintage market loves old stuff, like my Boss DM-2). Also, have you had success using the 12V power on 9V pedals?
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Post by blademaster2 on Nov 8, 2018 9:53:16 GMT -5
I need to know first what the Jaguar uses to make a comparison (I have not looked yet), but you are correct that the 'middle' control switch on a Condor just connects the selected pup straight out through the volume control and there is no capacitor in the circuit at all.
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Post by blademaster2 on Nov 7, 2018 10:47:36 GMT -5
I own a Condor from 1967. The switches for tone are, in my view, quite limiting. Here they are:
- The 'low' switch connects a 10nF capacitor from the signals of the pickups (which are connected by their own individual switches) directly to ground. I find it a bit too muffled and has no adjustment to alter it once selected. - The 'middle' switch adds no capacitance to the pickup signals and passed them straight through. This is by far my favourite setting. - The 'high' setting adds a series capacitor of 3nF to the pickup signals, cutting the low frequencies. This sounds okay but it thins the tone and I prefer the richer tone of the pups on their own.
In addition to this, the electronics has an 'accompaniment' switch that introduces a 50k potentiometer, shunting to ground, onto the pickup signals to add a second volume adjustment in parallel with the 250k potentiometer main volume control. I seldom use this, as it slightly reduces the highs while reducing the volume.
Overall, I prefer the pickups straight out. The neck pickup is my favourite (similar to a Strat). I found that you can switch more than one pickup on at a time and it thins the tone like a Strat does, but I am not sure if it is stressing the plastic interlocks on the switches or not so I do not do that often.
In summary, the Condor electronics is limiting but I do like the guitar and its playability.
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Post by blademaster2 on Oct 29, 2018 11:20:04 GMT -5
This is close to the systemic noise challenges that my team encounters all of the time in my day job.
My initial thoughts are to use a common power supply that has better load regulation (does not alter its voltage output when faced with changing levels of current drawn from it across a wide range of frequencies), also referred to as lower output impedance. If that is not desirable or possible, then separate power supplies that are all referenced to the common 'ground' voltage (outer connections on the jacks, and not the centre) might work just as well.
If the memory man uses an internal switching power supply for local regulation, your external common supply might need to be able to supply current at pretty high frequencies without added noise on the voltage. This could even mean it is influenced by the power cabling resistance/inductance and be very difficult to eliminate entirely. As such this might continue to be a challenge, so separating the supplies might still be needed to give you the least noisy results.
Beyond using the separate supplies, which works as you have said, trying a different supply might do the trick. If not then go from there until the problem is resolved.
That is my 2-cents on it.
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Post by blademaster2 on Oct 12, 2018 15:11:28 GMT -5
Yes, that end of the potentiometer needs to be grounded for biasing, otherwise it only biases the transistor Q2 with leakage current from the capacitor and whatever it can draw from the 100k resistor on the base of Q1.
When the potentiometer is adjusted to zero this capacitor is bypassed. It actually looks like something is still odd there, but I would need to look into it more closely to see what might be different from what I usually see. Often the single-ended 9V power is split for opamp circuits, and capacitors like these are used to AC-ground the signal while maintaining the mid-point DC level as the bias ground. With this circuit, having no op amps in a feedback configuration, the bias might be changing all the time with different adjustments and capacitors like this are needed to maintain a zero-DC-bias level for the audio signal.
And yes, it looks like the base of Q2 needs the signal from the collector of Q1 and cannot be left open.
Does that make sense to everyone out there?
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Post by blademaster2 on Sept 26, 2018 10:32:25 GMT -5
Was looking at another thread in this forum: guitarnuts2.proboards.com/thread/7399/amp-humsAnd filter caps are brought up as a potential source of the problem in the amplifier discussed in that thread. Given what I've described, is that a possibility I should look into? With this notion it might be worth assessing more closely what the noise sounds like that you are hearing from the amp. Buzzing and humming sounds indicate something like power supply noise and might implicate the power supply filter capacitors, but hissing (closer to white noise) would be less likely from the supply and comes from amplification of low-level thermal noise (shot noise, for example) in a component that is usually at the front end of the amplifier in the preamp.
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Post by blademaster2 on Sept 25, 2018 12:13:30 GMT -5
This might be silly to say, but I once thought that my AC15 was excessively noisy until I saw that I had the volume turned up on the unused input channel and I was playing clean from the other channel so the Master was up on full. The noise was 'hissy' (white) rather than hum or other indications of a guitar picking up on something like an antenna. It was a 'Doh' moment for me.
In your case you said it happens less when everything is unplugged from the amp, however the noise usually is not white coming from a guitar (I do not know if the AC15 has a shorted input that is switched when a cable is plugged in - my AMPEG V4 does). It also appears that you have no electronics such as stomp boxes or a preamplifier, but if you did they can create white noise, too.
If nothing simple like the above makes any sense, then it becomes more challenging. I have never traced my amplifier issues to tubes themselves since I play relatively infrequently, but perhaps they may be the culprit. In very sensitive circuits the type of resistors can influence noise (carbon resistors versus wire wound or metal film resistors) but that would require changing them (in the input stages of the amplifier circuit where gain is highest) and I doubt that they are likely to change and create noise like you are hearing but I understand that it is possible.
Sorry for the randomness of the above thoughts.
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Post by blademaster2 on Aug 30, 2018 15:45:48 GMT -5
Hey, no worries on my account.
Just relax and enjoy our amazing instrument at your own pace. Glad to hear you are able to play and enjoy it, and that the passive distortion has some merit.
I have been fiddling with my own experiments in tone and gear, combined with the various settings on my guitars. There are endless combinations and I love to hear new tones from old gear and simple mods.
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Post by blademaster2 on Aug 7, 2018 8:21:54 GMT -5
Update:
When I installed the speaker output jack into the Micro Cube I made the (not unusual) decision to mount the jack directly onto a newly-drilled hole on the housing. My first try did not install it, but only wired it in as an experiment and it worked fine.
Mounting the jack onto the chassis made the amp go totally silent.
The speaker outputs on this amplifier need to be isolated from the chassis. I figured this is because, as a battery-powered amplifier, to maximize power output it probably uses a bridge that will reverse the polarity of the DC power from the batteries depending which phase of the signal it is driving to the speaker. I probably should have known this beforehand.
Isolating this jack using a grommet did the trick (and looks okay, too).
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Post by blademaster2 on Jul 27, 2018 14:46:25 GMT -5
Putting an ext speaker jack into these little amps is a great idea, as I did on my Marshall MG10. But you come up against the added bass/guitar cab compensation that is built in, to try to thicken up the tone of the small speakers, leading to some boominess when a full cab is used. It would be nice to be able to switch out that part of the EQ circuit. Yes, if the EQ on the Micro Cube offered bass control it would improve things on a few of the modeled sounds that are boomy, but fortunately not all of them exhibited excessive boom. The tight, punchy tone was impressive on most settings. It does make me wonder why Roland offered three interfaces on the back - Rec Out plus two AUX inputs of 1/4" and 1/8" - instead of an external speaker output in place of the added input.
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Post by blademaster2 on Jul 26, 2018 13:38:29 GMT -5
My son has had a Roland Micro Cube amplifier for a while (hardly plays it) and it sounds amazing for such a little, battery-powered combo. I always felt that it needed more bass (as expected, with its 5-inch speaker), and my attempts at plugging its 'Rec' outputs directly into my studio, or into a larger high fidelity amplifier, never produced tones that I liked as much.
I tried an easy modification of adding a switchable external speaker output to the amplifier and plugged it in to drive a 2x12 Celestion Vintage 30 cabinet.
Some of the tones were a bit booming, but others were very nicely balanced and the built-in effects of this little 'head' really sounded good to me. I especially liked the firebreathing, 'wet' metal distortion sound (far heavier than my Marshall combo), and the flange and phase were great effects with clean or distorted sounds.
Another important attribute of this amplifier is that the slightly-distorted sounds it has, where the gain knob is around 50%, are also great for that little bit of edge for blues playing.
This little modeling head gave lots of variety and was actually much louder - with clean volume - than I would have expected.
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Post by blademaster2 on Jul 18, 2018 11:37:30 GMT -5
I agree with Newey - you would need to cut that channel in the bridge to be very flat and accurate along the bottom in order for it to have the same tone. It is much easier to shave down the saddle, and I cannot see how either of them would sound any different if they are done perfectly.
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