# Pitch Shift Speed Ratio Calculator MCP for AI Agents MCP > The Pitch Shift Speed Ratio Calculator instantly figures out the exact audio parameters you need for varispeed pitching. It determines the playback speed multiplier, new BPM, and adjusted duration when changing a track's pitch without complex DSP math. ## Overview - **Category:** utilities - **Price:** Free - **Endpoint:** https://edge.vinkius.com/vk_preview_Gvil2nlWeQ3pxDJEsID2B5IB53i5odDwpG4XrplK/mcp - **Tags:** audio, pitch-shift, bpm, varispeed, dj-tools, music-theory ## Description Pitch shifting an audio loop requires precise calculation to keep your tracks sounding right. This MCP handles that math instantly. You can tell it how many semitones you want to shift, and it calculates the necessary playback speed multiplier. From there, you get all the supporting data: how long the clip will be and what its new BPM must be. It’s perfect for DJs or sound designers who need to match keys across different tempo tracks. Instead of opening a spreadsheet, running complex math formulas, and hoping your numbers line up, this tool gives you verified ratios in seconds. You just connect it through Vinkius and let your AI client do the heavy lifting. ## Tools ### get_speed_rate Calculates the necessary playback speed multiplier when you specify how many semitones you want to pitch shift by. ### reverse_semitone_lookup Determines the required number of semitones needed to achieve a precise target speed ratio for your audio track. ### transform_bpm Calculates the new tempo (BPM) after you change an audio loop's playback speed using a specific ratio. ### transform_duration Calculates how long an audio clip will be after applying a variable speed adjustment ratio to its original length. ## Prompt Examples **Prompt:** ``` If I want to raise the pitch of a loop up 3 semitones, what speed ratio should I use? ``` **Response:** ``` **Pitch Shift Calculation** * **Target Semitones:** +3 * **Required Playback Multiplier:** 1.259 You need to run the audio at about 126% of its original speed for that shift. ``` **Prompt:** ``` My loop is 140 BPM and I slow it down by a ratio of 0.8, what's the new tempo? ``` **Response:** ``` **Tempo Adjustment Report** * Original BPM: 140 * Applied Ratio: 0.8 * **Calculated New BPM:** 112 The track will play at 112 beats per minute. ``` **Prompt:** ``` How long will a 5-second sound effect be if I speed it up by 2? ``` **Response:** ``` **Duration Transformation** * Original Duration: 5 seconds * Speed Ratio Applied: 2.0 * **New Calculated Duration:** 2.5 seconds The clip will play back at half its original length. ``` ## Capabilities ### Calculate multiplier from pitch shift Determine the required playback speed factor needed to hit a specific target pitch change, measured in semitones. ### Find semitones from desired ratio Figure out how many semitones you need to shift if you already know the exact speed ratio you want to use. ### Adjust BPM for speed change Calculate the new beats per minute (BPM) of a musical loop after you adjust its playback speed by a specific factor. ### Determine new clip duration Figure out the exact resulting length of an audio clip when applying a specific speed change ratio to its original time. ## Use Cases ### Matching a sample key to a beat loop A sound designer needs to make sure a vocal sample matches the key of a new drum track. The agent uses `get_speed_rate` to find the multiplier, and then confirms the resulting tempo using `transform_bpm`, ensuring perfect harmonic alignment. ### Creating seamless DJ transitions A DJ needs to transition between two tracks that have different tempos but need to share a common key. The agent uses `get_speed_rate` and then calculates the new timing using `transform_duration`, making the pitch shift mathematically sound. ### Re-timing an old recording for modern music A producer has an archival piece of audio that needs to fit a 128 BPM track. The agent uses `reverse_semitone_lookup` and then calculates the required speed factor, using `transform_bpm` to finalize the new tempo. ### Checking loop consistency across multiple sections An engineer is editing a song with many repeating audio loops. They use the calculator to confirm that changing the playback rate of one section (e.g., 1.2x) results in a predictable and usable duration via `transform_duration`. ## Benefits - Stop guessing ratios. Use `get_speed_rate` to get the exact speed multiplier needed when you know your target pitch shift in semitones. - Maintain perfect timing: Calculate new tempo using `transform_bpm`, guaranteeing that adjusting a track's speed doesn't mess up its rhythm or BPM. - Plan transitions accurately. Use `transform_duration` to see exactly how long a sample will be when you slow it down or speed it up, preventing awkward cuts. - Work backward easily. If you know the final ratio but not the semitone shift, use `reverse_semitone_lookup` to find your target pitch. ## How It Works The bottom line is, it removes all the complex math from varispeed pitching so you get accurate data instantly. 1. Start by providing your initial parameters, such as the target pitch shift in semitones or the desired speed ratio. 2. The MCP processes this data using the necessary calculations to find the corresponding multipliers, new BPMs, and adjusted durations. 3. Your AI client receives a clean set of numbers that you can immediately use to adjust your audio source. ## Frequently Asked Questions **What is the varispeed method?** The varispeed method involves changing the playback speed of an audio file to alter its pitch. This process naturally changes both the tempo (BPM) and the duration of the clip. **How can I find the speed multiplier for a specific semitone shift?** You can use the `get_speed_rate` tool. Simply provide the number of semitones you want to shift (positive for higher pitch, negative for lower), and it will return the required ratio. **Can I calculate the new BPM after a speed change?** Yes, use the `transform_bpm` tool. By providing your original BPM and the playback ratio, you will get the new tempo.