{"id":19383331,"url":"https://github.com/mdouchement/ampeg-heritage-b-15","last_synced_at":"2026-06-22T10:31:14.973Z","repository":{"id":79843968,"uuid":"427114045","full_name":"mdouchement/Ampeg-Heritage-B-15","owner":"mdouchement","description":"Custom Ampeg Heritage B-15 schematic","archived":false,"fork":false,"pushed_at":"2022-08-27T17:43:42.000Z","size":20464,"stargazers_count":3,"open_issues_count":0,"forks_count":0,"subscribers_count":2,"default_branch":"main","last_synced_at":"2025-02-24T17:15:40.660Z","etag":null,"topics":["ampeg","amplifier","b-15","hb-15","heritage","schematic","tube","valve","vintage"],"latest_commit_sha":null,"homepage":"","language":"Go","has_issues":true,"has_wiki":null,"has_pages":null,"mirror_url":null,"source_name":null,"license":null,"status":null,"scm":"git","pull_requests_enabled":true,"icon_url":"https://github.com/mdouchement.png","metadata":{"files":{"readme":"README.md","changelog":null,"contributing":null,"funding":null,"license":null,"code_of_conduct":null,"threat_model":null,"audit":null,"citation":null,"codeowners":null,"security":null,"support":null,"governance":null,"roadmap":null,"authors":null,"dei":null,"publiccode":null,"codemeta":null}},"created_at":"2021-11-11T19:10:20.000Z","updated_at":"2023-08-11T06:03:18.000Z","dependencies_parsed_at":null,"dependency_job_id":"96bebc11-5b51-4c13-b28c-8736f4b45a11","html_url":"https://github.com/mdouchement/Ampeg-Heritage-B-15","commit_stats":null,"previous_names":[],"tags_count":0,"template":false,"template_full_name":null,"purl":"pkg:github/mdouchement/Ampeg-Heritage-B-15","repository_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/mdouchement%2FAmpeg-Heritage-B-15","tags_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/mdouchement%2FAmpeg-Heritage-B-15/tags","releases_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/mdouchement%2FAmpeg-Heritage-B-15/releases","manifests_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/mdouchement%2FAmpeg-Heritage-B-15/manifests","owner_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners/mdouchement","download_url":"https://codeload.github.com/mdouchement/Ampeg-Heritage-B-15/tar.gz/refs/heads/main","sbom_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/mdouchement%2FAmpeg-Heritage-B-15/sbom","scorecard":null,"host":{"name":"GitHub","url":"https://github.com","kind":"github","repositories_count":286080680,"owners_count":34645680,"icon_url":"https://github.com/github.png","version":null,"created_at":"2022-05-30T11:31:42.601Z","updated_at":"2026-05-26T15:22:16.424Z","status":"online","status_checked_at":"2026-06-22T02:00:06.391Z","response_time":106,"last_error":null,"robots_txt_status":"success","robots_txt_updated_at":"2025-07-24T06:49:26.215Z","robots_txt_url":"https://github.com/robots.txt","online":true,"can_crawl_api":true,"host_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub","repositories_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories","repository_names_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repository_names","owners_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners"}},"keywords":["ampeg","amplifier","b-15","hb-15","heritage","schematic","tube","valve","vintage"],"created_at":"2024-11-10T09:25:36.436Z","updated_at":"2026-06-22T10:31:14.957Z","avatar_url":"https://github.com/mdouchement.png","language":"Go","funding_links":[],"categories":[],"sub_categories":[],"readme":"# Ampeg HB15\n\nThis project is a custom modification of the original Ampeg Heritage B15.\nYou can download the schematic [HB15.pdf](HB15.pdf).\n\n![IMG_20220104_171503_nometa](https://user-images.githubusercontent.com/6150317/184535948-74a372d0-8c94-4d86-b55a-14d9e0250598.jpg)\n\n## Warnings\n\n- Use **6L6GC** valves that support 500V at the screen\n- Always checks that all capacitors are discharged\n  - Even if the 470k 2W resistor shoud discharged the capacitor\n\n## Valves\n\nValves used in this project:\n- TAD - 6L6GCM-STR REDBASE\n- Philips USA as JAN 12AT7WC (6201) [NOS military grade]\n- JAN 6SL7WGT Philips               [NOS military grade]\n- Shuguang 6N9P J level             [NOS military grade]\n\n## Custom mods\n\n- The 100K 2W resistor in parallel with the standby switch reduce all the inrush current which is better for the capacitors\n- Boost switches increase the gain of the triode by adding a bypass capactor\n- Enable or disable the bright capacitor (boost in 8kHz)\n- Effects Loop (buffered) is built to be transparent and you can do severals things around:\n  - Enable or disable the effects loop\n  - Can be used as a buffered preamp out\n  - Can be used as an input for a \"preamp in a box\"\n  - Can be used as distortion stage on the cathode follower by increasing the send volume\n    - *Eventually a clean boost of the preamp*\n- Post Phase Inverter Master Volume (PPIMV) allowing to push the preamp while keeping the amplifier not too loud\n- Negative Feedback loop for rumble fix and different voicing (see schematic)\n- Midranges boost is a custom version inpired from Pignose B100V amp\n- Adding a 4.7nF capacitor in series with C1 and C3 to cut sub frequencies\n  - It may be a side effect by replacing all 22nF by 47nF in order to support a 5 strings bass\n  - It also due to the frequency response of my PF-210HE cabinet which have a greater low frequencies response\n  - 3.3nF may be better depending your cabinet (and taste)\n\n## Tips\n\n- Use a rubber seal inside the chassis to easily mount a APEM 644 for example\n- Use teflon tape and rubber seal to insulate metalic jack plug (e.g. Switchcraft 11) from the chassis to avoid ground loops\n- Avoid soldering ground on the potentiometer's cover (gound loops enabler)\n\n\n## Tools\n\n- [KiCAD](https://kicad.org)\n  - https://gitlab.com/kicad/code/kicad\n  - https://github.com/KiCad\n- [DIYLC](http://diy-fever.com/software/diylc)\n  - https://github.com/bancika/diy-layout-creator\n- [LiveSPICE](https://github.com/dsharlet/LiveSPICE)\n- [Micro-Cap](http://www.spectrum-soft.com/index.shtm)\n\n## Resources\n\n- https://ampeg.com/support/files/Schematics/\n- http://www.valvewizard.co.uk/index.html\n- https://www.ampbooks.com/mobile/amplifier-calculators\n- http://www.guitarscience.net/tsc/info.htm (tonestack calculator)\n- https://trioda.com/tools/triode.html (Loadline calculator)","project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fmdouchement%2Fampeg-heritage-b-15","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Fmdouchement%2Fampeg-heritage-b-15","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fmdouchement%2Fampeg-heritage-b-15/lists"}