{"product_id":"sterling-st77-mod-service","title":"Sterling ST77 Mod Service","description":"\u003cp\u003eThe Sterling ST77 is a copy of the ADK A-51 \/ MXL 2001 in a larger mic body. The ST77 mics that we've seen use a typical low-cost 32mm Chinese K67 capsule, with plastic clamping rings.\u003c\/p\u003e\n\u003cp\u003eThe circuit in this mic has numerous problems, resulting in a high noise floor and high distortion under moderate SPL. \u003c\/p\u003e\n\u003cp\u003eOur mod service replaces the entire signal path of the mic. \u003c\/p\u003e\n\u003ch3\u003eCapsule choices\u003c\/h3\u003e\n\u003cp\u003eYou can choose the RK-12, RK-47, or our custom K67 from the T-67 microphone. All three designs work well with the linear circuit we will install.\u003c\/p\u003e\n\u003cp\u003eThe service price on this page includes your choice of capsule. \u003c\/p\u003e\n\u003ch3\u003ePlatinum Circuit\u003c\/h3\u003e\n\u003cp\u003eNew in 2026, we have developed a new revision of a single-stage JFET\/transformer topology specifically for the ST77. The core circuit design is shared by our popular T-series microphones. But in this version, we've taken advantage of the ST77's larger housing to upgrade all of the components. \u003c\/p\u003e\n\u003cp\u003eAll electrolytics are our own bespoke audio grade parts. Filter caps are oversized and bypassed. Noise filtering is excessive. The JFET is a modern, high-grade design that is individually biased, and configured to run it higher current. \u003c\/p\u003e\n\u003ch3\u003eTransformer Options\u003c\/h3\u003e\n\u003cp\u003eWe have two transformer options. Both offer excellent performance. The Platinum transformer has slightly better resolution. Its higher cost is due to higher-purity copper windings, and import fees from Europe.\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003ch2\u003eCompatibility\u003c\/h2\u003e\n\u003cp\u003eThis mod is for the Sterling ST77 only. \u003cbr\u003e\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003ch2\u003eHow it works\u003c\/h2\u003e\n\u003cp\u003eAfter you buy this service, see our \u003ca href=\"https:\/\/microphone-parts.com\/pages\/mic-mod-service-policies\"\u003eService Policies page\u003c\/a\u003e for instructions on packing and shipping your mic. Be sure to print the Service Request form linked from that page. On the Service Request form, specify which capsule you prefer: RK-47, RK-12, or K67D.\u003c\/p\u003e\n\u003cp\u003eThe typical turnaround time is 5 business days. We can provide more detailed turnaround time estimates after you purchase the service.\u003c\/p\u003e\n\u003ch2\u003eCosts\u003c\/h2\u003e\n\u003cp\u003eThe mod service includes the parts, installation labor, and testing. Return shipping charges (domestic US only) are included for the microphone and power supply; if you send the entire TC suitcase, we would invoice you for additional return shipping fees.\u003c\/p\u003e\n\u003ch2\u003eAvailability\u003c\/h2\u003e\n\u003cp\u003eThis mod service is open to US residents only. \u003cbr\u003e\u003c\/p\u003e\n\u003cp\u003e(Residents of other countries might find that it costs less to purchase a \u003ca href=\"https:\/\/microphone-parts.com\/collections\/microphones\"\u003efinished microphone\u003c\/a\u003e.)\u003c\/p\u003e","brand":"Microphone-Parts.com","offers":[{"title":"Standard","offer_id":53440955023654,"sku":null,"price":599.0,"currency_code":"USD","in_stock":true},{"title":"Platinum","offer_id":53440955056422,"sku":null,"price":689.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0867\/8438\/files\/st77-internal.jpg?v=1783373308","url":"https:\/\/microphone-parts.com\/products\/sterling-st77-mod-service","provider":"Microphone-Parts.com","version":"1.0","type":"link"}