Ear fatigue and making mods

[PremiumPlus]

Quite often when I've spent the day at my bench, whether its making tweaks or major circuit surgery I have problems with my ears, or more likely, the way the mind works when it hears sounds over and over. I tend to keep a nice speaker cab about 8 or 10 feet away, pointed at my bench. A guitar on a stand next to the bench, and then as I work I can see what it sounds like, and make decisions on the next step based on real time tone. So far so good.
The problem is that the next day the amp doesn't always sound the way I thought it did on the bench. Same guitar, same cab, different room, different day. Do your ears get fatigued after long periods of exposure? I'm in my mid 50s and I know that my ears suffer from high frequency roll off, but this is different; I think that the mind gets numb and less perceptive during long period exposure to music (or anything, really). The next day I hear things differently! The reason for this post is that yesterday I took a parted out bassman head and built a Marshall JCM 800 preamp for the dirt channel and a slightly tweaked Bassman preamp for cleans. When I finished it sounded terrific. I'm getting ready to play it again and I hope it sounds as good as it did yesterday.
Discussion?

[defaced]

Absolutely. I have noted it when mixing songs. The advice I've read about ear fatigue is to do your best in one sitting, then come back at it a different day.

[Regis]

Yes absolutely I get ear fatigue. I notice it alot when mixing and at the end of a band rehearsal.

Of course the ringing in my ears from thirty years of aural assault by loud guitar amps doesn't help either.

[tubeswell]

Yep mee too. Try sticking the modded thing in a cupboard for a week and coming back to it. Often I find a few days distraction by other things brings a new insight. Also doing a recording of the modded sound helps to evaluate it over time (if you can remember which mod went with which recording).

[Chuck H]

One thing that has helped me cope with ear fatigue when I do modifications, I try to focus on one issue at a time. As in, "This amp needs a softer attack". I'll try some things until THAT issue sounds right and sometimes I'll listen to it again on three consecutive days before I make my decision to move on into another issue or continue to work on that one. I also do all my bench testing through a dummy load with a low level output. That way I can fix the macro stuff at low volumes and minimize high volume testing.

Chuck

[dai h.]

I'd find I'd get ear fatigue VERY quickly when exposed to loud volume and that they (my ears) would recover after a while after ceasing the high volume exposure. So I think it's a bad idea to tweak at high volume since you'll get a false impression of what the amp sounds like. I remember occasions where I'd stay up real late tweaking thinking, "This sounds great!" only to get up and try the amp first thing next morning and have the amp sound like poop (namely very harsh). Also another time where I was copying an album from CD to tape and using a BBE Sonic Maximizer (also staying up late) where I apparently had it and added waaaay too much high processing. The next day, (on my way to school) when I put the tape in my walkman and listened, it was seriously godawful (the highs). Ear fatigue is real and so is degradation that comes with age though I think it differs with sex (male or female and not "getting some or not getting some" --female hearing generally being better) and maybe individual difference(s in hearing). Plus hearing damage, and maybe experience as well (making for different perception).

[chipaudette]

To further confuse the issue, I am nearly convinced that both my guitar amp and my home stereo both sound better after 11pm.

Sometimes, it probably sounds better because I've had a nice dinner and a bottle of wine with my wife. Other times, though, I'm stone sober. I turn it on and, BAM, I'm struck with how much better it sounds.

Could things sound better at night because everyone in the neighborhood has stopped using their washer/drier/dishwasher/HVAC ? Or am I totally delusional?

Chip

[dai h.]

I've read that from some sources. I have no idea if that is true, though it is my understanding that noise can indeed come in via the AC line even from say another building nearby. (On one web site I found interesting) one recording studio guy turned to a balanced power power supply which is supposed to help cancel common mode(I think it was) noise, eliminate current flow on the ground line in order to solve the perceived problem. IIRC he claimed it helped give more consistency to the sound. My take is that running on balanced power can help solve ground loop problems, plus give a slight improvement to the audio (not drastic night and day difference), which is maybe justified for professional situations.

[mac1amps]

Yet ANOTHER factor that I've noticed over the years of playing/repairing amps, is that amps will sound slightly different from day to day (especially true for older/vintage amps). I can remember many situations where a certain amp/guitar combination sounded amazing! Great sustain, "sweet" sounding high-end, solid (not "farty" sounding) low end, and all at a "pleasant" volume level. And then, the same "rig" on another occasion, even in the same room, just sounds "okay". I've always suspected factors such as humidity or possibly barometric pressure to be involved, and perhaps the effect temperatures can have on [some] capacitors ("'lytic" caps as well as "signal" caps).

[PRNDL]

Last time I was at Larry Roger's shop he had a beautiful Princeton Reverb that he had finished working on, and wanted me to listen to it.

At first, I thought the punchy highs were painful, until I moved to the side of the speaker, then it sounded much better.

My question is how loud are the amps?

If they are loud enough to cause concern over ear fatigue, you may want to consider building a padded speaker enclosure with a mic and a monitor (T-amp) so that you can listen to the amp at low volume levels.

Something simple could easily be built with plywood, or plexiglass if you want to it to be visible for customers.

If it looks good, I wouldn't be surprised if many wanted you to build them one.

Actually, I'd like to make one -- does anyone know where there are plans and material suggestions?

[Enzo]

All your senses "fatigue." The blinding outdoor light when you first emerge from your hole becomes normal after a couple minutes. The cat box that needs changing and assaults your nose fades to the background after a bit, or the overly perfumed lady two tables over. Your ears accustom themselves to whatever you are hearing.

[Steve Conner]

Everyone's ears and brain have a pretty big random component. That's why I don't see the point in obsessive tweaking of minor tonal changes, if your taste can vary by several dB from day to day.

Daz on this forum is the best example of this, he spends all night changing capacitors, and then the next evening he decides that he doesn't like what he's done and agonizes over some other changes, and on and on it goes with no end in sight.

I refuse to spend time worrying about any mod to audio equipment that makes less than 3dB difference to some measurable parameter of it. That cuts down the range of options enough that I can usually leave guitar amps unmolested and just enjoy playing them.

[hasserl]

I like to keep a reference amp close by, when I've been tweaking a new amp I'll compare it back to back with a known good amp, a reference point.

[daz]

Wow, I had no idea you know everything about me from how long i spend at a time to how long i wait to decide something is good or not. What are you, a friggin' physic? Or maybe just phyCO? Seriously, don't make judgments on what i do here where you cannot see by my posts. For christ sakes man, your opinions aren't worth listening to if your judgments are made w/o nearly enough info to substantiate them. Do me a favor and stop responding to and about me, will ya? If you want to insult people here make it someone else because i won't stand for that cr@p.

[Dave Curtis, dB AudioTech]

My take is that running on balanced power can help solve ground loop problems, plus give a slight improvement to the audio (not drastic night and day difference), which is maybe justified for professional situations.

Which, in fact is the only situation it's allowed to be used; commercial or industrial installations. So says the NEC (NFPA 70) Art. 647.3