[SPAM] Re: [TekScopes] Can capacitors
Quote: "I actually saw a guitar player and another technican try several rectifier tubes in a guitar amplifier, all new and identical from the same case, to find the one that sounded best. It was almost a seance!"toggle quoted messageShow quoted text
Even sadder is that many of those same performers seeking the best sound have severely degraded hearing from excessive volume.
My father did mixing for a local club & got to know quite a lot of performers.
The volume of "feedback" needed for many of them was astonishing because their hearing was so bad, & they needed ever higher feedback over time.
In a similar vein, as an apprentice I went through a commercial TV studio that made commercials.
They had just put a new sound studio in about a year before.
The staff were complaining that the amplifiers were sagging in the afternoon but long investigations & multiple chart recorders on all the voltage rails etc didn't show anything.
The mixing staff were questioned individually several times & they were all adamant that there was a problem.
One of the techs had a girl friend who was an audiometrist & he gave her a tour during operating hours.
When she walked into the sound section, he mentioned their problems.
The staff were mixing sound at the time.
She hurried him out & gave an accurate diagnosis of the problem.
The amplifiers were not failing, but their ears were reacting to the high volumes which were more than high enough for permanent damage.
Hurried investigations were made about maximum legal safe levels & limiters fitted to the amps.
All the mixing staff immediately went out on an indefinite strike.
When we went through, the volume controls all had wide skirts that limited rotation by hitting a stopper.
The stopper was a push button switch.
When you pushed the switch in, it allowed further rotation of the volume control but it also caused a printer to print out an indemnity form for the company.
The staff took the form to the office where they were witnessed making their signature, it was put on file, & then they could personally operate the bypass switch in the office.
It required both the push button on the volume control & the office switch to be operated to allow bypass.
The person filling out the form had to operate the bypass, office staff were forbidden from touching it.
On 06-December-2020 2:46 pm, Renée wrote:
having dealt with numerous guitar players and audiophiles in repairing their stuff....not sure which group is most gullible - audio folks, guitar players, and some other groups that are in the psycho bin where misinformation abounds. ( worst one was where he plugged the amp in to a power outlet and... never mind...)..and here I thought I was picky in what I hear being a jazz and symphony musician/engineer but then I am a reasonably knowledgeable realist (with a budget)....
The volume is definitely an issue. I am not sure how rectifier tubestoggle quoted messageShow quoted text
could change sound, but amplifier tubes might be selected for just the
right amount of even harmonic distortion, and low odd harmonic
distortion. Even harmonics sound good and odd harmonics sound bad. The
more they are overdriven, the more the distortion. So, I might grant
them a little leeway there, but there are other ways to get the
distortion you like.
When it comes to test equipment, I don't think distortion is desirable.
On Sat, Dec 5, 2020 at 10:25 PM Brian Symons <email@example.com> wrote:
Chuck Harris <cfharris@...>
I hate to get into this thread, but a lot of the guitar ampstoggle quoted messageShow quoted text
are very poorly designed in the biasing department, and a slight
change in bias voltage, which could happen with a slightly different
resistance rectifier tube, could make a significant change in sound.
Did it in this case?... Could the player have heard the difference?
Your guess is as good as mine.
I copied a Fender Tweed amplifier once, and it sounded way too clean.
It wouldn't distort the way a real Fender Tweed should, which causes
great disappointment for electric guitar players, as Tweeds made an
iconic sound in much of the 50's and 60's RR music tracks.
Anyway, I found that the problem was the Russian 6V6 tubes I used in
the output stage. When they were biased as a Fender Tweed does, they
were too clean. Using a pair of NOS RCA 6V6's made it a completely
different amplifier.... So did clamping the bias voltage divider at
24V with a zener, and using the Russian 6V6's.
Don't get so excited in your zeal to make fun of others that you
forget your objectivity, and electronics knowledge...
OBTW, threads like what this thread is devolving into have gotten
droves of tekscopes members banned in the past. Don't tempt the fates,
unless that idea appeals to you for some reason. Dennis is a more
tolerant guy, but Michael Dunn is still around.
Brian Symons wrote:
Quote: "I actually saw a guitar player and another technican try several rectifier