Talk:Guitar amplifier

Proposal: Break out Guitar-dedicated articles
http://en.wikipedia.org/wiki/Talk:Distortion#Proposed_Article_Titles_and_Changes

The refactoring is in-progress. MichaelSHoffman 03:39, 8 August 2006 (UTC)

The refactoring is done. MichaelSHoffman 08:50, 8 August 2006 (UTC)

Modelling amps:most common forms section
In the Most Common Forms section it states:

 "With the advent of microprocessors and digital signal processing in the late 1990s, "modelling" amps were developed that can simulate a variety of vintage amplifiers' vacuum tube sounds without the use of vacuum tubes. As of 2005, these modelling amps account for a minority of amp sales" 

Is there a source for the sales data? I worked in a 20 store chain in New England for 4 years, and Line 6 was one of the best selling lines. During the 2004-2005 X-mas season we coudn't keep the little 15-30watt jobs in stock. maxcap 16:15, 8 August 2006 (UTC)

I removed the statement. "Minority" is meaningless; would need to list % of tube amps, solid-state amps, and digital modelling amps. MichaelSHoffman 02:14, 16 August 2006 (UTC)

Moved list of amp makers
The list of amp manufacturers ought to be moved to another page. Where? MichaelSHoffman 21:28, 10 August 2006 (UTC) Done. List of guitar amp brands MichaelSHoffman 23:25, 10 August 2006 (UTC)
 * The article was poorly made and ill-kept, to say the least. So, as it tried ti mimick the information already contained in Category:Guitar amplifier manufacturers then I redirected it to the rightful source of that information -- Mecanismo | Talk 20:00, 20 June 2009 (UTC)

hybrid amps
A recent edit in Tube amp section (4 Sept 12.201.87.113)highlights a need for a short additional section on tube/silicon hybrids (Marshall valvestate etc). I'm not up to starting it but will be happy to contribute. 210.246.25.233 09:05, 8 September 2006 (UTC) Had an unsuccessful log-in, so signature for above comment should have read: RichardJ Christie 09:09, 8 September 2006 (UTC)

Possibly Biased towards Valve amps.
The section describing how a valve amp works tends to be biased in favour of them. There is little detail on Solid state amps, and they are compared "off the back" of valve amps.
 * That's possibly because it is a section on how valve amps work ;-) RichardJ Christie 08:52, 17 November 2006 (UTC)

Clean/dirty
What do these things mean in a guitar amplifier context? Is it a specific reference to distortion, or does clean simply mean an absence of effects? Or is it something else altogether?

-- TimNelson 11:44, 22 February 2007 (UTC)


 * From a technical standpoint, distortion is an effect, and an effect is a distortion. Both techniques involve modification of the input signal.172.132.137.91 07:30, 22 April 2007 (UTC)


 * Good point. But that still doesn't explain what people mean when they say that one channel is the "clean" signal, and one is the "dirty" signal; I guess I'm asking from the guitar culture point of view -- I know what it would mean from an electrical engineering point of view.  Thanks again,
 * -- TimNelson 11:40, 8 May 2007 (UTC)

"Is it a specific reference to distortion, or does clean simply mean an absence of effects?"

The short answers: "yes" to the first; "no" to the second. The terms "clean" and "dirty" are properly specific to distortion; not only in guitar amps but in audio systems in general.

In such systems, be they for recording, sound reinforcement, broadcasting, etc., a "clean" signal refers to one that exhibits very little distortion, that is, its waveform is very nearly identical to the input.

Strictly speaking, in the case of amplification circuits or components, where the desired action is a change in amplitude of the potential difference ("voltage"), current ("amperage") or power ("wattage"), any deviation from a "flat" frequency response is a form of distortion, although it is nearly always treated as a different phenomenon. The same holds for hum (usually 50 or 60 Hz line frequency and their respective harmonics), noise (tape hiss, thermal noise, etc.), and cyclical frequency shifts ("wow" and "flutter") produced buy the rotating parts of systems employing analog media, such as magnetic tape or phonograph records.

Therefore, in practice distortion refers to those elements of the output which are not present at the input, such as harmonics, intermodulation products, phase shift, "clipping" (flattening of the crests and troughs in the waveform) and the products of clipping, and Doppler effects produced by speaker excursion.

An output signal rich in even harmonics may give the signal a pleasing "warm" (low-end harmonics) or "sweet" (high-end harmonics) sound, whereas odd harmonics tend to impart a raspyness to the sound.

A "dirty" signal refers to one with an abundance of distortion products that impart a raspy or "fuzzy" sound, especially clipping products. Many guitarists prefer vacuum tube or tube/transistor hybrid amplifiers because of the distortion characteristics of tubes. They distort the audio signal at all levels, producing a pleasing "warm" sound when modestly driven, and a sound that is less harsh compared to transistors when overdriven, as they produce a more curved waveform when driven to clipping rather than a nearly square wave flattening.

Driving an amplifier circuit into distortion also compresses the audio signal -- the waveform's crests and troughs are "clipped" as the circuit reaches its maximum output. (One might say that the signal has to "squeeze" through the circuit.) When the circuit is adjusted for very high gain, even a low level input pushes it to its maximum, and the output level remains high even as the input fades. This phenomenon produces the "sustain" a guitarist gets from his amp or outboard effects when he turns up the "distortion" knob. It also seems to account for many guitarists confusing "distortion" with "sustain". Both can and are achieved by overdriving an amplifier circuit, but they're not the same thing. (Guitar construction, for example, is a significant factor in producing desirable sustain, as the sympathetic vibrations in the guitar's body and neck are conveyed to the strings via the guitar's "hardware", principally the bridge, but also the nut and tailpiece.

An output may include copious amounts of "effects" -- radical equalization, reverb, phasing, and delay effects such as doubling, echo, flanging and chorus, yet still produce a "clean" sound. Old style hardware reverb devices, such as spring and plate reverbs, as well as reverb chambers, may produce an abundance of harmonics, but again we don't refer to these effects as "distortion" in audio circles.

Cheers, Rico402 (talk) 11:06, 17 July 2010 (UTC)

Linear vs Switching
Solid-state amplifiers still require power transformers

Don't some guitar amps have switching supplies?66.217.164.74 21:49, 27 August 2007 (UTC)


 * Switching power supplies still have a transformer. —Preceding unsigned comment added by 71.212.137.2 (talk) 16:44, 5 October 2007 (UTC)


 * Not all switching supplies. Very many have a single inductor (not coupled to another, as in a transformer) or capacitor as the energy storage device.

Analog Sensitivity; Device Failure
""Hard core" tube amp fans may not be able to tell the difference, in a blind auditory test, but will most always choose to play a tube amp because of its analog sensitivity."

Analog sensitivity is a meaningless phrase, and is not used in electronics. It should be deleted, or the sentence edited to say something like "Although they can't actually hear the difference, tube amp fans still prefer tube amps." (Well yes, that's why they're called tube amp fans. Duh!)

"When a tube fails, it is replaceable. While solid state devices are also replaceable, it's usually a much more involved process..."

But transistors don't fail! In a properly designed amplifier which doesn't overstress the devices, the lifetime of semiconductors is virtually unlimited. Tubes, on the other hand, have a very short life. The only reason they're easy to change is because they need to be changed on a regular basis!

As usual with discussions of guitar electronics, this article is not objective but is full of half-truths, unsubstantiated statements and personal opinions. Please try harder.

--84.9.75.142 14:34, 24 March 2007 (UTC)


 * I was about to mention these two things as well. --Aslkvbiwbegv 16:49, 24 March 2007 (UTC)


 * It may be possible to discern a tube amp from an SS clone. But amateur blind testing is not as rigorous as DB-ABX.  Subjectivism vs objectivism is beyond the scope of the article. —The preceding unsigned comment was added by 172.132.137.91 (talk) 07:23, 22 April 2007 (UTC).

Replace
As someone who's never edited Wikipedia before, would there be great offense caused if I replaced this entire page? I'm doing a research project, and part of the literature review is going to be the history of amps, the way that vacuum tubes work, an examination of the controversies of solid state vs tube etc., and possibly a discussion on tone, it's subjectivity and the psychoacoustic aspects of this. It's all going to be properly referenced and linked. It will probably be around 1500 words but might be up to 3000 or so.

I guess I'd post it my proposed article and we could discuss it? I don't want to offend anyone or anything, but I feel that it would be a lot more in depth (and properly referenced, for one thing) then what's currently up there. There would be a few things I'd add that are on this page now, too.

Comments?


 * I have been around for a while and IMO someone who has never edited Wikipedia should not start by replacing a page. It is almost always best to improve on the work of others. I learn more by improving than by starting from scratch. ~KvnG 01:08, 23 July 2013 (UTC)

Wiki Project
I've added this article to the guitarist's Wiki project, which will hopefully get us more help on this article. I also added a discussion page header here, hoping to remind people to sign their posts. ;) Enjoy!  --Dulcimerist 19:46, 30 August 2007 (UTC)

Amp Placement
One thing new guitar player don't know is how far from your amp to stand to hear yourself properly, If you stand directly in from of your amp their is a "dead zone" of 3 or 4 feet. In that "zone" the tone and volume are not what they are at 4 or more feet. The new players i have jammed with are practically standing on top of there amp with the cabinet blasting at there knees and still can't hear themselves with any clarity, so they turn it up & up & up, meanwhile the other people in the band are only hearing that one person. Anyone else have thoughts on this subject?

Marco —Preceding unsigned comment added by 70.51.54.177 (talk) 16:28, 23 April 2008 (UTC)

I think it is necessary to add a paragraph on software modeling amps (Native Instruments Guitar Rig, Waves GTR, Amplitube) —Preceding unsigned comment added by Bf2008 (talk • contribs) 19:13, 15 June 2008 (UTC)

Materials
What are amps generally made of? I believe wood is standard, but what type. Do they all have that mesh front? What purpose does the mesh serve? How about that outer wrapper, is that vinyl or leather? Some general info for complete ignoramuses would be great. ---Ransom (--71.4.51.150 (talk) 19:25, 6 August 2008 (UTC))

Confusion over Volume
The article states that "The relationship between perceived volume and power output is not immediately obvious. A 5-watt amplifier is perceived to be half as loud as a 50-watt amplifier (a tenfold increase in power), and a half-watt amplifier is a quarter as loud as a 50-watt amp."

Then later it states "Peak output of tube amplifiers is heard as being up to three times louder than similar rated solid state guitar amps. For example, a 30-watt tube amplifier can be perceived by the listener to be as loud as a 100-watt solid state amplifier, particularly when both are driven into maximum distortion."

It would seem these two statements are inconsistant. Using the logic of the first part a 10 watt amp is twice as loud as a 1 watt amp and a 100 watt amp is three times as loud as a 1 watt amp. Thus the second part should say For example, a 1-watt tube amplifier can be perceived by the listener to be as loud as a 100-watt solid state amplifier, particularly when both are driven into maximum distortion.

Is this correct? Peboyle (talk) 10:04, 10 December 2008 (UTC)


 * No. Wattage isnt like that, its a logarithmic curve. double the power doesnt mean double the volume. "Peak output of tube amplifiers is heard as being up to three times louder than similar rated solid state guitar amps" is probably true. You may also want to know that bass amps always seem  to be less loud than guitar amps (hence bass practice amps being 25-50w whereas guitar ones are 10-25w in comparison)  —Preceding unsigned comment added by 86.16.153.191 (talk) 16:10, 30 June 2009 (UTC)

From here: "How loud is 50 watts? With human perception it sounds only twice as loud as 5 watts, and it sounds only half as loud 500 watts (and only 1/4th as loud as 5,000 watts). Here's a list of how humans perceive power." which references this information. TubeGod (talk) 15:23, 17 April 2014 (UTC)


 * This discussion began from an apples and oranges, and never proceeded.


 * It is true that perceived output is closer to log than linear, therefore "a 10 watt amp is twice as loud as a 1 watt amp" is accurate enough for most purposes. See also decibel: "The human perception of the intensity of sound and light approximates the logarithm of intensity rather than a linear relationship (Weber–Fechner law)".


 * However, WRMS is not a measure of raw output power, and I will spare you the details. Suffice that in real-world use, a five-watt valve (tube) amplifier is MUCH louder than a five-watt solid-state amplifier.


 * (And before someone asks: a "hybrid" amp with a solid-state power stage is still a solid-state amp.) Weeb Dingle (talk) 16:30, 4 September 2017 (UTC)

going Direct to  to PA  from  Just  an  amplifier  head
1) could i just use an amplifier head without speakers but go direct to a PA system

2) Could i go direct with a amplifier with 1 12" speaker into a PA, but the Amplifier doesn't have a Direct out, how would, and could i do it.  —Preceding unsigned comment added by 67.85.247.51 (talk) 06:25, 2 January 2010 (UTC)

what's that noise?
When I touch the plug to my skin, instead of plugging it into the guitar, it makes odd noises. It didn't for my roommates, whom the amp belonged to. It made different sounds for various objects as well. Does this have anything to do with why I can't wear watches(body electricity screws them up) & can shine copper by holding it? What exactly is it picking up? —Preceding unsigned comment added by 156.34.185.213 (talk) 06:18, 28 August 2010 (UTC)

Jazz Guitarists
Jazz guitarists don't 'favor the "colder" sound of solid-state amplifiers'. They favour the cooler sound of solid-state amplifiers, Daddio! —Preceding unsigned comment added by 193.178.95.4 (talk) 16:29, 1 March 2011 (UTC)
 * Jazz guitarists using arch-top semi-hollow guitars create tone in the guitar, so they don't need much coloring from the amp. In some Jazz styles, the treble is seriously rolled off, so the amp doesn't even make much difference. Jazz guitarists playing distorted styles (e.g. fusion) using solidbody guitars will still use tubes, at least in the preamp.192.139.122.42 (talk) 23:38, 29 April 2011 (UTC)

Zero-Hysteresis Transformerless tube amplification
In this edit on 19 Mar 2014, Drmies removed this text

Zero-Hysteresis Transformerless tube amplification -- In 2009, Milbert introduced a tube guitar amplifier which eliminates the traditional audio output transformer (and all traditional power supply magnetics) by using Berning's patented ZOTL circuit to almost perfectly (and bi-directionally) mate power tubes (in any combinations) and speaker load, resulting in transfer characteristics being accurately and fully conveyed between tubes and speaker(s).

and asserted, "(Zero-Hysteresis Transformerless tube amplification: no verification, no suggestion that this esoteric brand needs special mention in the general article (only difference--transformerless))".

It should be pointed out that there are many advantages offered by the patented ZOTL Technology, including ultra light-weight (due to no audio output or bulky power supply magnetics); automatic standby capability; ability to use any common vacuum tubes in any combinations (and have them automatically biased); freedom from 60 Hz powerline hum; ability to automatically drive any practical output impedance(s) and also total-opens and dead-shorts even at full power without destruction (of non-existent traditional audio output transformer) due to high-voltage flyback, arcing and consequent insulation breakdown; and an unequaled purity of tube tone due to the complete elimination of all otherwise inescapable audible parasitics. TubeGod (talk) 15:53, 17 April 2014 (UTC)

Johnny Burnette?
Currently in the History section of this article is the following sentence: "In the 1950s, several guitarists experimented with distortion produced by deliberately overdriving their amplifiers, including Goree Carter,[1] Joe Hill Louis,[2][3] Ike Turner,[4] Willie Johnson,[5] Pat Hare,[6] Guitar Slim,[7] Chuck Berry,[8] Johnny Burnette,[5] and Link Wray.[9]"

I would recommend removing Johnny Burnette from this list. I am assuming he has been cited because of "Train Kept A-Rollin'", but there is some debate as to whether he actually played on that track or whether it was Grady Martin.Design (talk) 08:05, 23 April 2014 (UTC)

when is a guitar amp not a guitar amp?
ANSWER: when it's a Bassman!!

There is significantly little discussion in this article as to what EXACTLY defines "a guitar amplifier." One of the most popular amps among guitar players in the 1960s was in fact Fender bass amps, specifically the Bassman — as shown in this article's second photo. In Don Rich: In the early days, Rich would play Owens' 1951 Fender Telecaster through a Fender Bassman amplifier. Steppenwolf was certainly another. Cobain used a Bassman at least once, on "Drain You." Skim through the list of Fender amplifier users: Mike Bloomfield, Mike Campbell, John Fogerty, Josh Homme, Brian Setzer.

Yet that photo caption is the ONLY use of "bass" in the entire article.

This is highly significant, as the Bassman was the literal template for later "classic" amps from Marshall and other companies. Weeb Dingle (talk) 18:51, 4 September 2017 (UTC)

bloat vs. truck-sized gaps
I just now noticed that there is not even attempt to explain how the "tone" section of a standard amp works — these knobs are barely mentioned at all, and mostly in the last few paragraphs. Yet section 6.3 is reserved for volume knobs. If this is significant, shouldn't it be somewhere near the top?

Why is it that there appears to be an underlying assumption that "guitar amp" implies tube/tube circuitry? (For example, Distortion, power, and volume: Power output.) Solid-state and hybrid amps don't exist at all in History. Weeb Dingle (talk) 08:39, 29 November 2017 (UTC)

It appears that History is about half pilfered (almost word-for-word) from a Vintage Guitar article, and half original research. And the list of "several guitarists who experimented with distortion" needs to cite a credible source, otherwise it's a magnet for trivia about "first" when the truth is likely that the noisy edge was being widely used YEARS before any of the cited guitarists ever recorded (or rather convinced the studio engineer to allow) it.

The following Structure section is even worse, a bloggy essay offering no citations.

Do "practice amps" really need to be mentioned NINE times in the article? Wouldn't it be better to have an early subsection where the concept is explained? Weeb Dingle (talk) 20:57, 10 March 2019 (UTC)

Trivia at Hanwell
Back in the mid to late 1980s, three NHS worker friends of mine rented the flat above the shop, the girls knew the history of the owner and told everyone. It was very impressive, the kitchen in particular was very modern looking with hidden lighting around the edge of the ceiling and under wall cabinets, common now but ahead of it's time then, presuming it was fitted out around 1980. Jim Marshall still owned the flat and the shop beneath was IIRC a music shop, but I would guess rented out to someone else. Ianmurray5 (talk) 18:00, 5 May 2024 (UTC)