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Path of signal from turn table to speaker

Hi all, if you could humor a fledgling "audiophile" still learning... can anyone specify how a signal get from a turntable to the speakers? My understanding is that pure analog circuits are for many reasons not common. This means that the signal must first be converted by an ADC (analog to dig convertor). This signal then travels through the amp circuitry and eventually reaches a DAC which then outputs to the speaker. Is this decently accurate?

The second part of this question relates to how an amplifier can affect this signal. I have a rega preamp so I don't need an amp with a phonostage. If this is the case I have a hard time understanding how one amp will differ from another for record playback. I know that amps all differ in there capabilities but the basic formula does not change. Analog signal to digital and then back to analog. When purchasing an amp for records... should i basically just purchase for that amps capabilities and nothing else from the input standpoint?
jwl244
noromance's avatar
noromance
9,439 posts
 
Forget DAC and all digital for a minute.
Phono amp > Preamp > Power amp > speaker.
All of these can be analog. In fact it’s preferable.
The phono amp is special. It contains equalization circuitry to compensate for the frequency curve needed to cut a record.
The Preamp drives the power amp and allows selection of sources. It can have a DAC built in. The pre and power can be together in an integrated amp.
millercarbon's avatar
millercarbon
12,531 posts
 
Right. Its all analog. There is no digital at any point. The signal in the record groove is analog, but it is equalized with bass way down and treble way up in what is called RIAA equalization. Its also very low level (volume). You can play a record back without a phono stage but it will not be very loud and it will sound tinny with no bass. The phono stage amplifies this weak signal and equalizes it to sound right. Its one of the most essential and difficult things to do in all of audio because the signal is so weak and involves so much EQ. 

The phono stage is all analog. But it can be all tube, part tube and part solid state, or all solid state. It can be a separate component or it can be a card or circuit built into a pre-amp or integrated amp. There's a lot of different ways to do it, and that may be where some of the confusion is coming from. 

One amp or phono stage differs from another tremendously. Because of the tremendous gain and EQ its one of the widest ranges of sound you will find and makes a huge improvement when you get it right.
yeti42's avatar
yeti42
287 posts
 
There are turntables with inbuilt ADCs and a USB output but these are generally not taken seriously. There are also phono pre amps that digitise, I think Linn have one and Devialet do this too, the wisdom of doing so is debatable.
Most modern recordings are though digital and converted to analog for pressing to LP. It remains a source of puzzlement that such an LP played back on a good turntable through analog amplification can beat the digital file of the same recording, both played on similarly priced but carefully setup equipment. 
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