Hey guys, a gradual lack of bass in my system. Could this be the valves aging ?
The four power tubes I replaced last year, but not touched the 6N1 pre and buffer ones in five or so years.
Any ideas pls as I don't have any valves I can swop and test with.
Amp: Yaqin MC-10L
Thanks
The four power tubes I replaced last year, but not touched the 6N1 pre and buffer ones in five or so years.
Any ideas pls as I don't have any valves I can swop and test with.
Amp: Yaqin MC-10L
Thanks
Hi Barbieboy,
Unlikely bad coupling caps unless they aren't rated for a high voltage. It is more likely that the tubes may possibly be getting weak, and that would also be accompanied with poor sound quality. I haven't got a schematic for that, so I can only talk in general terms. Sorry.
To help us out, is this an old amplifier, or is it recent manufacture? If it's an old amplifier, have you replaced the coupling capacitors yet?
-Chris
Unlikely bad coupling caps unless they aren't rated for a high voltage. It is more likely that the tubes may possibly be getting weak, and that would also be accompanied with poor sound quality. I haven't got a schematic for that, so I can only talk in general terms. Sorry.
To help us out, is this an old amplifier, or is it recent manufacture? If it's an old amplifier, have you replaced the coupling capacitors yet?
-Chris
Hi Barbieboy,
So that amplifier is new manufacture then. Age related problems will not be your problem.
Did this issue start after you did the "upgrades"? If it has capacitors from cathode to ground, you should also check those.
-Chris
It was pure heaven for a year after the upgrade, gradually become shy of bass
Hi Barbieboy,
At this point you need to actually measure the output some way. You have to run a tone and measure the output to find out where it is really rolling off. Only after then can you look for problems. Otherwise, you won't know whether to look at the speaker (could have a swelled voice coil) or the amplifier. I can't see any common faults in an amplifier that is that new. Even your changes worked for a year before trouble showed up.
One possibility. I can't see the inside of the chassis,so this is a guess more than anything else. is it at all possible that a solder connection has become disconnected? Using your eyeballs is a first step in troubleshooting a problem. Solder joints certainly can fail after a year. Do you take this amp on the road?
-Chris
At this point you need to actually measure the output some way. You have to run a tone and measure the output to find out where it is really rolling off. Only after then can you look for problems. Otherwise, you won't know whether to look at the speaker (could have a swelled voice coil) or the amplifier. I can't see any common faults in an amplifier that is that new. Even your changes worked for a year before trouble showed up.
One possibility. I can't see the inside of the chassis,so this is a guess more than anything else. is it at all possible that a solder connection has become disconnected? Using your eyeballs is a first step in troubleshooting a problem. Solder joints certainly can fail after a year. Do you take this amp on the road?
-Chris
Thanks guys,
Just had a neighbour pop in and he cranked the volume up higher than I normally do and said "you see, there is bass there". But I don't want to listen that loud, he thinks the problem is the amp is not powerful enough to produce low volume bass (52WPC into 4ohm speakers).
Ok he has a point, but this does not explain why it sounded nice before !
Just had a neighbour pop in and he cranked the volume up higher than I normally do and said "you see, there is bass there". But I don't want to listen that loud, he thinks the problem is the amp is not powerful enough to produce low volume bass (52WPC into 4ohm speakers).
Ok he has a point, but this does not explain why it sounded nice before !
Hi Barbieboy,
-Chris
Nope, that isn't reasonable. I have a 35 wpc amplifier that drives speakers with low bass notes no problem. If you are playing at low volume, you may need to engage loudness, or turn the bass up a little. Your amplifier should deliver the same power to speakers of 8 or 4 ohms if you are using the proper taps.he thinks the problem is the amp is not powerful enough to produce low volume bass (52WPC into 4ohm speakers).
-Chris
[1] Make a passive bass-boost circuit. One easy solution if all the rest of the circuit is OK.
[2] If both channels are the same, then it is quite unlikely that there's something systematic going wrong with the amplifier.
[3] How old are you? One of the things that begins to decline less obviously with age is bass ear response. We all know about 'failing treble'. But bass goes too…
[4] Is there a preamp between all your sources and the amplifier? Could easily be something within that, not the final amp.
[5] TRY YOUR CDs on another system, with different 'everything'. Play it at the volume level you like. Is there bass? If so, … then yah… something about your system might be amiss. If not… ears… age… expectations… false memories…
[6] Back in the "old days" one had stereos with 'tone controls'. They're pretty good at boosting bass, if that's what you like. Too bad they're near-gone these days. Just saying...
GoatGuy
[2] If both channels are the same, then it is quite unlikely that there's something systematic going wrong with the amplifier.
[3] How old are you? One of the things that begins to decline less obviously with age is bass ear response. We all know about 'failing treble'. But bass goes too…
[4] Is there a preamp between all your sources and the amplifier? Could easily be something within that, not the final amp.
[5] TRY YOUR CDs on another system, with different 'everything'. Play it at the volume level you like. Is there bass? If so, … then yah… something about your system might be amiss. If not… ears… age… expectations… false memories…
[6] Back in the "old days" one had stereos with 'tone controls'. They're pretty good at boosting bass, if that's what you like. Too bad they're near-gone these days. Just saying...
GoatGuy
Hi Goaty,
[1] don't know how to make one.
[3] 56 and the very same thing went through my mind, and didn't know that...
[4] No preamp, laptop, J.River, Asio, into usb Dac, into amp.
[5] Have no other system, but changed the speakers, made no difference. Wish I had another amp to play with.
[6] Could play with the EQ in j.river. OMG going back to tone controls in old age ? :/
[1] don't know how to make one.
[3] 56 and the very same thing went through my mind, and didn't know that...
[4] No preamp, laptop, J.River, Asio, into usb Dac, into amp.
[5] Have no other system, but changed the speakers, made no difference. Wish I had another amp to play with.
[6] Could play with the EQ in j.river. OMG going back to tone controls in old age ? :/
Hi Barbieboy,
I'm not familiar with those tubes. Normally you would go with a known good brand. Anything from the Reflector factory, or New Sensor in New York would be a good bet.
-Chris
Hi Chris, they ship from Russia:
6N1P MATCHED PAIR 6922 6DJ8 ECC88 7308 VOSKHOD ROCKET TUBE XII-84 2PCS | eBay
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