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User3747830
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2026-11-06
Everything arrived safely and functions perfectly.
13 types of op-amps (HPA4 x 2 units also listed separately)
$145.20
$188.759996032715
30% OFF
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Product Details
Description
Specifications
Care Guide
Selling off my desktop audio equipment for my PC setup, I am listing these operational amplifiers.
This is a bulk listing of 13 types of operational amplifiers. They come in a large, dedicated case for op-amps. They will not be sold individually. Includes 5 each of 8-pin sockets, with and without gold plating, and a removal tool. All have been tested, but please understand that all sales are final (no claims, no returns) in the unlikely event of a defective item. Below is a summary of my personal notes and website impressions, but these are purely personal opinions. It's inherently difficult for an amateur to put the differences in sound into words. These are the results of a rather tedious but blissful time spent searching for my preferred op-amps by switching between and testing two FOSTEX HPA4 units. As I have replaced amplifiers 4 times and speakers 3 times over approximately 7 years, please forgive any inaccuracies in sound quality comparison.
I believe these are ideal for those who want to enjoy audio by replacing op-amps. Some of these are now discontinued and difficult to obtain. Please note that there may be misreadings of model numbers, but the items shown in the photos are correct.
β MUSE8920B03: A reliable op-amp frequently used in Japanese products such as Luxman and Accuphase.
β‘ MUSE02: Successor to the 01, the Japanese standard.
β’ TI4652: Made by Texas Instruments (formerly National Semiconductor), highly rated despite its low price.
β£ THS4601
β€ NE5532P: Inexpensive but said to have been used in McIntosh (?), a veteran with a clean sound quality free of distortion.
β₯ OPA828: Successor to the 827, featuring rich bass and delicate treble.
β¦ OPA827: A stable sound quality that excels with vocals, rated as higher quality than the 627.
β§ OPA1612: Produces energetic and clear sound from high to low frequencies.
β¨ OPA604AD: A captivating (?), exceptional piece that delivers a thick sound across all frequency bands.
β© OPA627BP: The high-end standard for op-amps, a must-try at least once if you're considering replacing op-amps.
β β LT1115CN8: Impressively clean sound and excellent cost performance.
β β‘ TI1634cN8: Straightforward sound quality.
β β’ OPA627AU
Category
Headphone Amplifier / Dac
Condition
No noticeable scratches or marks
Shipping
Included in price (by seller)
From
Tokyo
Daily Cleaning: Use a soft brush or damp cloth to gently wipe away dirt. Avoid harsh chemicals. For mesh areas, use diluted mild detergent and a soft brush.
Drying: Air dry in a cool, shaded place after cleaning. Avoid direct sunlight or high heat, which can cause fading and glue deterioration.
Storage: Stuff with paper to maintain shape when not in use. Store in a dry, ventilated area to prevent mold. Rotate between multiple pairs to extend lifespan.
Usage Notes: Designed for basketball. Not recommended for hiking, long-distance running, or other specialized sports where different performance features are required.