The manual provides approved substitution lists:
| Stock Tube | Approved Substitute | Effect (per manual notes) | | :--- | :--- | :--- | | EL34 | 6CA7, KT77 | KT77 increases headroom slightly | | 12AX7 | ECC83, 5751 | 5751 reduces gain, lowers noise | | 12AU7 | ECC82, 5814A | 5814A recommended for tighter bass | jadis da30 manual
Maintenance Schedule:
Report ID: JDS-DA30-TECH-01 Date: [Current Date] Subject: Review of Operational Manual & Technical Specifications The manual provides approved substitution lists: | Stock
The DA30 is deceptively heavy due to its massive output transformers. Solution: This is not covered in the manual
Cause: The DA30’s VU meters are driven by the output signal. If they are stuck, the meter driver board may have cold solder joints. Solution: This is not covered in the manual. Resoldering the small PCB near the meters usually fixes it.