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OP-amp metronom

Operational amplifier for the analogue converters TDA1540 and TDA1541A. CD players usually contain double operational amplifiers with two amplification stages in one housing, following the analog converter. One half is responsible for the voltage conversion of the audio signal, the other half is used for stabilisation with an upstream low-pass filter. However, these very different tasks are performed by identical halves. The OP-amp metronom combines two different individual OPs on one board as a Plug'n Play replacement.

•  optimized single op-amps as double op-amp
•  better heat balance to conventional adapters
•  minimal mass change due to new micro pin (pure silver option)

Double operational amplifier

OP-amp metronom
•  1x OP-amp double 825-604 22buy
•  1x OP-amp double 604-825 22buy
•  1x OP-amp double 604-604 22buy
•  1x OP-amp double 825-825 22buy

Place one double OP-amp in the shopping cart, then you can set the required quantity in the shopping cart.

•  1x pure silver micro pins option 4buy

In the shopping cart is placed as extra pins for one double OP-amp, then you can then set the required quantity in the shopping cart.
Note that silver is a softer material than the brass commonly used for pins, so the pins can bend more easily. However, they can also be straightened more easily without breaking off as with brittle brass. It is possible to use them in sockets, but soldering them in tightly is recommended.


Single Operational Amplifier

OP-amp metronom single
•  1x OP-amp single 604 12buy
•  1x OP-amp single 825 12buy

Place one single OP-amp in the shopping cart, then you can set the required quantity in the shopping cart.

•  1x pure silver micro pins option 4buy

In the shopping cart is placed as extra pins for one single OP-amp, then you can then set the required quantity in the shopping cart.
Note that silver is a softer material than the brass commonly used for pins, so the pins can bend more easily. However, they can also be straightened more easily without breaking off as with brittle brass. It is possible to use them in sockets, but soldering them in tightly is recommended.



Examples for different assemblies
Following the converter I recommend an AD825, then as a filter and buffer an OPA604 - so a double OP-amp with different equipment per half. Solder audio operational amplifiers firmly, the use of sockets is disadvantageous here. Different circuits in CD players can use either the first or the second half of a double OP-amp first. In some devices both variants are used.

2x 825-604
The most common variant with the same wiring per stereo channel. For e.g. all Philips from CD100 to CD304 and also subsequent models such as CD460, CD650, CD880 ...
Grundig CD903, CD8400MKii, CD9000 ... CD9009 has 825-604 but followed by another 3x 604-604 as filters and output drivers, so a total of 8 double OP-amp.

2x 604-825
Some Marantz models use the second half of the op-amp first, such as. the models CD40 and CD50 ...

825-604 und 604-825
Models with different wiring for each stereo channel are e.g. Revox B225, Marantz CD84 and Sony CDP 337ESD ...

825-825
Marantz CD94 MKII first uses 2x 825-825. A subsequent filter section also requires 2x 604-604 and 2x single 604.

single OP-amp
A Philips CD960, Marantz CD94 and some similar models use 4x single op-amps. So two 825 and 604 are required here.

Questions about other models please via email.


Note
We purchase our operational amplifiers directly from the manufacturers Analog Device and Texas Instruments / Burr and Brown. Such sought-after operational amplifiers are offered individually in the auction house at prices below those of the manufacturer. Verified offers were marked with wrong imprint and could be identified as cheap NE5532/NE5534 by measurement. Keep in mind that originals have a higher price than fakes without adapter boards and low ground solder pins.


metronom-module V2.0
no oversampling bridge