{"product_id":"mariupol-jazz-preamp","title":"Mariupol Jazz Preamp","description":"\u003cp\u003e\u003cb\u003eMariupol Jazz Preamp\u003c\/b\u003e is a noise-free, high-fidelity reimagining of the legendary \u003cb\u003e\u003ci\u003eRoland Jazz Chorus\u003c\/i\u003e\u003c\/b\u003e preamp section, specifically targeting the op-amp topology found in the stereo JC-77 and the James Hetfield-approved JC-120H head. While the original amps are iconic, they are a family of varied designs; we focused on perfecting the op-amp architecture by completely redesigning the circuit for the modern era. To eliminate the noise floor inherent in the vintage units, we downscaled the resistance values and replaced the standard 4558 chips with Hi-Fi-grade \u003cb\u003eLM4562\u003c\/b\u003e op-amps for superior audio performance. We didn't stop there—the signal path is populated with high-quality film capacitors, even in the pico-farad range, a luxury never seen in mass-produced Roland amps. Powered by a custom modern switch-mode supply that boosts 9V to a massive \u003cb\u003e30V internal rail\u003c\/b\u003e. Whether used as a pristine clean preamp, a boost, or a 4-band EQ with Fender-style interactive voicing, the added \u003cb\u003eHi-Treble\u003c\/b\u003e control ensures your tone retains that crucial \"spark\" even at lower volumes.\u003c\/p\u003e","brand":"Drunk Beaver Pedals","offers":[{"title":"Default Title","offer_id":51800979538267,"sku":"PD-34","price":559.0,"currency_code":"PLN","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0790\/5833\/8139\/files\/drunk-beaver-pd-34-mariupol-jazz-preamp-1.webp?v=1764072283","url":"https:\/\/checkout.drunk-beaver.rocks\/products\/mariupol-jazz-preamp","provider":"Drunk Beaver Pedals","version":"1.0","type":"link"}