Ok, I will take it apart and try resolder absolutely everything in the next week or so
I knew my top end hearing is on the way out, but didn't know the low end was going too !
Gentlemen, before we get ahead of ourselves,
Age-related (for the OP! ) unlikely unless there is an ear-malady. I still hear bass fine at >80 ....)
Tube related: doubtful. Tubes do not discriminate between frequencies, they simply pass/modulate electron flow. You have also eliminated the loudspeakers as cause.
The circuit uses GNFB, which counters frequency discrimination. I would guess that something inside the gain loop will have to change considerably (> 50%) to cause audible frequency change. I would first go the the 220nF capacitor grounding the grid of V3(1) (Blast these scematics without component annotations.) If you can temporarily replace, even values fo 47nF would do for a listen.
Other than that one can go hit/miss until one gets lucky. Time to find a friend with a 'scope and signal generator; problem would then be easy to sort out.
Regarding your hearing: Hope not, but some malady is unfortunately not impossible. Seems the detected change was over years ....
Age-related (for the OP!
) unlikely unless there is an ear-malady. I still hear bass fine at >80 ....) Tube related: doubtful. Tubes do not discriminate between frequencies, they simply pass/modulate electron flow. You have also eliminated the loudspeakers as cause.
The circuit uses GNFB, which counters frequency discrimination. I would guess that something inside the gain loop will have to change considerably (> 50%) to cause audible frequency change. I would first go the the 220nF capacitor grounding the grid of V3(1) (Blast these scematics without component annotations.) If you can temporarily replace, even values fo 47nF would do for a listen.
Other than that one can go hit/miss until one gets lucky. Time to find a friend with a 'scope and signal generator; problem would then be easy to sort out.
Regarding your hearing: Hope not, but some malady is unfortunately not impossible. Seems the detected change was over years ....
Hi Guys,
The verdict after tests falls mainly on my hearing, sadly.
-Volume setting is getting lower and lower which means things are getting uncomfortable for me at even normal levels and the woofers just aren't getting driven.
Cure ? If there is one, am looking into sinus inflammation, dairy and sugar being the main potential culprits causing swelling in the Eustachian tube.
- Did hook up a 100w AV amp which is rather lean on the bass side, but had more bass than the 50w valve amp, just. So looking like need a good poweramp that can pump out 20amps would do the trick even at low level listening.
But first to lay off pizzas and sweet stuff, thanks for all your input, much appreciated
The verdict after tests falls mainly on my hearing, sadly.
-Volume setting is getting lower and lower which means things are getting uncomfortable for me at even normal levels and the woofers just aren't getting driven.
Cure ? If there is one, am looking into sinus inflammation, dairy and sugar being the main potential culprits causing swelling in the Eustachian tube.
- Did hook up a 100w AV amp which is rather lean on the bass side, but had more bass than the 50w valve amp, just. So looking like need a good poweramp that can pump out 20amps would do the trick even at low level listening.
But first to lay off pizzas and sweet stuff, thanks for all your input, much appreciated
I'm warmly proud of you, BB. For finding the cause, and admitting it. I can tell you (from experience) that there are a few good solutions, (like 'tone' controls) which need to be backed up by a separate amplifier-and-subwoofer solution. Be aware that when implemented, listening pleasure will be delightfully restored for you … but your neighbors won't be as amused. Personally, I purchased a couple of ALESIS RA–100 amplifiers (they're like $45 ea off EBay), and a couple of style-less large cabinet 1970s "hi fi" speakers; built a little high-cut filter (roll off starts at 250 Hz, but its easy to play with), and changed my system to a 4 speaker deal. Wow. (No tone control!) The RA–100 amps have HUGE overdrive capacity. And we don't need 0.0000001% THD for that Base, fellow Gramps.
Just saying…
GoatGuy
Just saying…
GoatGuy
Changes in hearing can be difficult to address so you are off to a good start, in the mean time has anything else in the system changed since the "bass went away?" Changes in room layout, furnishings, equipment and your actual listening position all play a role - are you sitting in a null?
The tone control/EQ options in J River are quite good and you can use a combination of parametric and graphic EQ to sort out deficits in the room response. Buy or borrow a cheap RTA or alternately a mic and pre to use with REW or similar software, measure your room response where you do most of your listening and adjust EQ to fix the worst dips. This can be a slow and painful process, but end result is worthwhile.
The tone control/EQ options in J River are quite good and you can use a combination of parametric and graphic EQ to sort out deficits in the room response. Buy or borrow a cheap RTA or alternately a mic and pre to use with REW or similar software, measure your room response where you do most of your listening and adjust EQ to fix the worst dips. This can be a slow and painful process, but end result is worthwhile.
Goat & Kevin.
Sorting out the hearing is the way forward. A good example having just dropped my door keys in the hallway and the clang was really quite painful. This is indicative of ear drum problem / inflammation issues. I am 56, my neighbour 82 and it did not hurt him as much.
Did try the EQ in J.River raising the 60Hz a tad, didn't like it much as added muddiness.
AVamp I tried (Yamaha RX-V771) I meant is lean in bass in 2 Channel Stereo mode. A krell-ksa50s would do the job, but too hard sounding for me. Or I hear the Cambridge Audio AZUR851W is neutral and has plenty of oomph at low level, but I don't have that sort of money.
Sorting out the hearing is the way forward. A good example having just dropped my door keys in the hallway and the clang was really quite painful. This is indicative of ear drum problem / inflammation issues. I am 56, my neighbour 82 and it did not hurt him as much.
Did try the EQ in J.River raising the 60Hz a tad, didn't like it much as added muddiness.
AVamp I tried (Yamaha RX-V771) I meant is lean in bass in 2 Channel Stereo mode. A krell-ksa50s would do the job, but too hard sounding for me. Or I hear the Cambridge Audio AZUR851W is neutral and has plenty of oomph at low level, but I don't have that sort of money.
Thanks Goat,
Yes imagine they do have the low end drive, did have a couple of similar amps driving 15" 1970s Tannoy Red studio monitors a few years ago. But studio amps lack detail and finesse. Soundstage pretty narrow too on these sort of amps:
A500 | Studio Monitor Amplifiers | Power Amplifiers | Behringer | Categories | MUSIC Group
Yes imagine they do have the low end drive, did have a couple of similar amps driving 15" 1970s Tannoy Red studio monitors a few years ago. But studio amps lack detail and finesse. Soundstage pretty narrow too on these sort of amps:
A500 | Studio Monitor Amplifiers | Power Amplifiers | Behringer | Categories | MUSIC Group
Your neighbour is talking nonsense. It is true that our ears are less sensitive to bass at lower levels, but if the amp is powerful enough to produce enough bass when turned up then it is powerful enough. One minor caveat: extra distortion due to the amp being overloaded can give the impression of bass, when the bass is not actually present. As you say, this does not explain why it has got worse (unless it was distorting, and now is not!).Barbieboy said:
Check DC conditions. Measure the frequency response. Check your loudspeakers.
PS Sorry - just seen the rest of the thread.
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B.B.,
If you are seriously worried about your hearing, don't base your conclusions on your amplifier, the neighbour's opinion (with respect) or what we say. Go to your doctor/healthcare professional or whatever that lofty profession is called your side. It might seem an expensive way, but any physiological problems should be sorted out that way first, for your own good as I am sure you will realise. It might just be treatable. As said I am also well on the wrong side of 50, had/have the same problems, had some treatment, and have to live with what remains. (Smart hearing aids: Hesitate to even think of the cost involved here ....)
Put that first, then you can address matters as is possible with electronics. Good fortune!
If you are seriously worried about your hearing, don't base your conclusions on your amplifier, the neighbour's opinion (with respect) or what we say. Go to your doctor/healthcare professional or whatever that lofty profession is called your side. It might seem an expensive way, but any physiological problems should be sorted out that way first, for your own good as I am sure you will realise. It might just be treatable. As said I am also well on the wrong side of 50, had/have the same problems, had some treatment, and have to live with what remains. (Smart hearing aids: Hesitate to even think of the cost involved here ....)
Put that first, then you can address matters as is possible with electronics. Good fortune!
One other thing to check: have you moved or otherwise unhooked your speakers and then reattached them? Could someone else have done so? It never hurts to check for proper matching polarity. If they are out of phase, the bass will disappear. Try reversing the cable leads on one of the speakers (turn the amp off first).
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