Before the MC boost transformer story, the first is the basic way to watch records. When listening to records on the turntable (record player), the record needle is used to convert the sound information engraved in the groove of the record disk to a music signal and play it back.
In general, preamplifiers for pre-main amplifiers and separate amplifiers have a dedicated phono equalizer (phono) input for listening to records. Connect the output terminal from the record player to this phono input and listen to music.
The record cartridge (record needle) is divided into two types, "MM (moving magnet type)" and "MC (moving coil type)," depending on the difference in power generation method to change the sound of the record to an electrical signal.
When records were usually at home, record needles were mostly MM-type. The MM type, which has a high output voltage and is easy to handle, can be connected to an amplifier with a phono input as it is and can enjoy watching records. Therefore, many of the MM types are inexpensive and durable.
The product page of the cartridge is here
https://www.exclusive-audio.jp/shop/products/list.php?category_id=27
Another type of MC (moving coil) cartridge is more complex and requires higher accuracy than MM cartridges. The sound response is good and the frequency range is wide, and the good sound is attractive. In general, it is an image of a MC cartridge that is "expensive and high performance," and the middle-to-high class is the main. In fact, many audio fans use MC cartridges overwhelmingly, and there are many products.
Although it is such a MC type, the output voltage is lower than the MM type in the structure, there is only an output of 1/10 or less of the MM type, only 0.1 to 0.3 mV.
Therefore, the volume is too small to use even if you put it in the fono input of the amplifier as it is. Therefore, to raise the output voltage to the MM type level without dropping the sound quality level, things such as a boost transformer and a head amplifier are required.
Because it is exclusive to MC cartridge, it is also called "MC transformer" or "MC head amplifier."
Product page of boost transformer is here
https://www.exclusive-audio.jp/shop/products/list.php?category_id=26
A boost transformer is more widely used than a head amplifier. The range of products is abundant, and various designs such as shape and size are available, and the price is also pinky. The voltage boost ratio is different depending on the winding ratio of the transformer, and the input impedance is divided into two types: HIGH (HIGH) and LOW (LOW). Since the mechanism is simple, the difference in performance and structure of the material of the core and winding greatly affects the sound, but each of them has its own personality and features a direct and powerful playback sound.
Head amplifier product page is here
https://www.exclusive-audio.jp/shop/products/detail.php?product_id=22
On the other hand, a head amplifier is an amplification element (semiconductor, etc.) that increases the input signal electronically, so power supply is necessary. The sound quality seems to be flat and wide range.
The boost transformer is strong and stable for noise without power supply, but depending on the installation environment, noise comes out from the outside, and ham sound is made even if the earth wire is not connected correctly, so be careful. Some head amplifiers require noise control around the power supply due to current flowing.
When choosing a boost transformer, MC cartridge is roughly different from LOW (LOW) impedance type and HIGH (HIGH) impedance type cartridge, so choose the boost transformer that fits the impedance as much as possible.
Click here for the Phono Equalizer product page
https://www.exclusive-audio.jp/shop/products/list.php?category_id=33
In addition to the phono equalizer built into the preamplifier and the pre-main amplifier, there is a single phono equalizer amplifier. Depending on the product, there are a wide variety of products such as MM input only, MC compatible model with built-in boost transformer, equalizer that amplifies ideal for MC cartridge using a large current output, so you can choose the combination and model according to your preference.
