Carol-Ann Custom Amplifiers OD-2 Series 운영 매뉴얼 - 페이지 9
{카테고리_이름} Carol-Ann Custom Amplifiers OD-2 Series에 대한 운영 매뉴얼을 온라인으로 검색하거나 PDF를 다운로드하세요. Carol-Ann Custom Amplifiers OD-2 Series 11 페이지. 50w & 100w amplifier
페이지 인쇄Replacing Tubes
50W Model: 2 x 6L6GC or EL-34, 3 x 12AX7, 1 x 5751
100W Model 4 x 6L6GC or EL34, 3 x 12AX7, 1 x 5751
With average usage we recommend changing your preamp tubes every three years. Only
buy the best quality tubes from a reputable supplier. We can recommend and/or supply
tubes to you.
V1 – Use a balanced, low noise, low microphonics 12AX7.
V2 - Use a balanced, low noise 12AX7.
V3 – Use a low noise 5751.
V4 – Use a balanced 12AX7
With average use we recommend changing your power tubes every 12 to 18 months.
Always use a matched set of power tubes from a reputable supplier. We can recommend
and/or supply these tubes to you.
When new power tubes have been fitted the Amplifier will require the new tubes biasing.
This is usually a job undertaken by a Qualified Technician. However, the OD Series does
not require the chassis to be removed in order to adjust the bias, and providing the owner
has a suitable bias probe, this job can be carried out with little difficulty. However if you
do not feel confident in any way, then always leave the job to a qualified Technician.
1. Remove the back panel from the cabinet.
2. Remove the old power tubes.
3. Replace the power tubes, with the bias meter attachment connected to the tubes.
Be extremely careful not to break the guiding pins. These tubes are orientated by
these plastic guides pins and can only be fitted in one way. If one breaks it is
possible to fit the tube incorrectly and damage almost certainly will occur to the
amplifer and/or tube.
4. Turn the Amplifier Power switch ON, leave the Standby switch off for now.
5. Let the Amplifier warm up for 1 minute.
6. Using a small flat blade screwdriver Locate the bias adjustment screw. It can be
found located between the power tubes as a recessed screw pot.
7. Turn the Standby Switch ON and watch the meter reading.
8. Once the reading has settled, adjust the screw pot so the meter reads 35mV for
EL-34's or 42mV for 6L6GC's (per tube).
9. Leave the Amplifier on for approx 30 minutes, then recheck and adjust if needed.
Note 1 : There will often be small differences (+/- 5mA max) between matched
tubes, always bias the amp using 'hottest'...i.e the tube that reads the highest mV
value as the reference point.
Note 2: Though the OD-2 has been designed so the bias voltage tracks the wall
voltage quite closely, it must be noted that in locations where large wall voltage
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