Although I've always had music in my life it's nearly always been via cd, now I've gone back to vinyl and only playing CDs on odd occasions, so a couple of idiot questions regarding a denon amp I've just acquired, it's a pma 350se and as a hi fi novice on hooking it up 2 things surprised me, 1) I had to buy a pre amp to play my turntable and 2) there are no bass or treble controls, why have amps changed this way? Or have I just always bought rubbish that was literally plug and play?
Newbie idiots advice please
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Amps with no tone controls became fashionable many years ago on the basis of "less circuitry... less chance to corrupt the sound". There is no right and wrong on that, just what your ideals are.
I guess not having an inbuilt phono stage suggests this amp was aimed and marketed at the CD user.
I guess not having an inbuilt phono stage suggests this amp was aimed and marketed at the CD user.
LP's come with an emphasis curve defined by the "RIAA" recording industry association or something, long defunct. This keeps the bass from knocking the needle out of the groove. The inverse RIAA curve should be built into a preamp for LP's. 45 RPM records have roughly the same curve, 78 RPM records were different. So what you here should be what was intended. I have a CBS brand stereo test record I bought about 1975 that allows one to test one's system by playing the record and determining if all frequencies in the sweep are at equal volume. If they are, your system is correct.
I test my systems now by playing a hifi recording of a Steinway brand grand piano. I know what those are supposed to sound like, having gone to a concert or two. With that knowledge you can assess your system performance on the basis of how accurate the sound is.
Other people use voice as a calibrator, but having heard Allison Kraus talk to her band on the way to the bus, the voice on stage as presented or recorded, and the voice live, can be quite different.
I test my systems now by playing a hifi recording of a Steinway brand grand piano. I know what those are supposed to sound like, having gone to a concert or two. With that knowledge you can assess your system performance on the basis of how accurate the sound is.
Other people use voice as a calibrator, but having heard Allison Kraus talk to her band on the way to the bus, the voice on stage as presented or recorded, and the voice live, can be quite different.
Is the ground wire from the turntable connected to the chassis of the preamp? This is necessary to prevent buzz. If connecting to the ground terminal of the preamp still gets buzz, you can try connecting it to a ground on the main amp. One of the chassis screws will likely work as a ground point if it doesn't have a handy ground terminal.
Wow that's a confusing statement. Or maybe it's just me.
When WHAT is connected to the Technics?
There is absolute silence AND an irritating buzz??
Is the buzz coming from the power amplifier or from the speakers?
Was it working OK for awhile and then suddenly developed the buzz?
Uh..careful with suggestions that sound like disconnecting mains protective earth.
Usually, turnatable arm ground is electrically isolated from signal ground and mains protective ground. It only acts as a shield connection to the metal tone arm parts, particularly the tubular arm and cartridge shell. It must be connected at least to chassis ground somewhere, to be an effective shield and if it's only to the amplifier chassis, it avoids a loop. I have seen arrangements on mass-market players where only the motor frame was connected to protective earth and the whole steel chassis was connected to the amplifer chassis.
By today's standards these would be considered dangerous and never permitted to be sold but they were safe enough for wide consumer use in their day.
Possibly, newer plastic turntables with low voltage supplies, don't have this same shielding arrangement.
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All hi fi equipment today comes with only 2 pin plugs and someone might have since connected a 3 core cable with earth and disconnecting it temporarily aids in troubleshooting.
This will depend on the portable appliance wiring rules in your country. In this country at least, all mains powered audio equipment must now be fitted with 3 pin connection leads, usually the ubiquitous detachable IEC type.
Old Technics turntables weren't and often arrived with US style 2 pin mains leads to fit switched, chassis mounted outlets on the amplifier but were always provided with a shield ground connection to the amplifier. Making that connection to protective earth from a separate player's mains connection instead, would couple AC into the signal and couldn't be used that way with a magnetic cartridge in the first place. If an internal mains earth connection was only to the motor or player chassis, that is different connection and is to meet a safety requirement which must be maintained. In my experience, this does not introduce hum.
My comment was directed at the suggestion of "...try disconnecting the earth connection in the plug...." If it somehow worked, the user is most likely to leave it that way, no? That is not a good idea without at least a rider clause about safety issues, considering forum rules and common sense in advising others probably unaware of the significance or differences in wiring regulations (and dubious safety provisions in 1970s-80s) from manufacturer to user even. Actually, I doubt there will even be an earth wire to disconnect in the player's mains plug.
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