I have had my line-1 since new and thankfully no issues.
Sonic Frontiers Line - 1 Volume Control
Has any owner of either a SF Line-1, 2 or 3 preamp experienced problems with the volume control? You may know that the control is in fact an optical shaft encoder.
I have had 3 failures of these units.
First pre-amp just "froze" after a few month's use, and was replaced with a brand new model (as opposed to being repaired).
The second unit also developed similar problems after 2.5 years use, though this time the fault was more severe in that the volume control would inexplicably "ramp-up" to maximum (95.5db) unassisted in any way. Took out a few KT88 tubes on one of my power amps before I get to it - and turn off. The preamp was fitted with a new shaft encoder and "logic" box (behind the fascia) under warrantee in 2000, and was fine until last month when the shaft encoder froze (yet again) after turning on from Standby. The unit will still funtion of course via the remote control, so its NOT the end of the world!Have sourced a replacement encoder and awaiting fitting by local techo.
Purpose of this question is to ask if any other owner of these series of otherwise very fine pre-amps have experienced similar problems?
(RH)
I have had 3 failures of these units.
First pre-amp just "froze" after a few month's use, and was replaced with a brand new model (as opposed to being repaired).
The second unit also developed similar problems after 2.5 years use, though this time the fault was more severe in that the volume control would inexplicably "ramp-up" to maximum (95.5db) unassisted in any way. Took out a few KT88 tubes on one of my power amps before I get to it - and turn off. The preamp was fitted with a new shaft encoder and "logic" box (behind the fascia) under warrantee in 2000, and was fine until last month when the shaft encoder froze (yet again) after turning on from Standby. The unit will still funtion of course via the remote control, so its NOT the end of the world!Have sourced a replacement encoder and awaiting fitting by local techo.
Purpose of this question is to ask if any other owner of these series of otherwise very fine pre-amps have experienced similar problems?
(RH)
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- 13 posts total
Interesting to see OP goes back to 06' although last post in 2018. Where as I dont post on here a whole lot my sense is that members are not notified of new posts unless their user name is noted in the post. I should verify this question in a current thread. lol.. At any rate, Im on my second Line 1 and have never had any problems with it nor with my first one. Although after hearing a ModWright LS100 in my system I was impressed at what I perceived to be a more musical and natural sounding synergy (s/s amp) And I sold the Modwright. Primarily because it is kind of big and really does not fit my standard size rack very well. The Line 1 of course is also full featured with all kinds of control via the remote and the original hockey puck remote is of course a keeper.. That being said Im still hunting for a 6sn7 based preamp--if you have not heard one its something to check out IMHO. |
I have had a Line 3 for a couple years now which I bought used on eBay and have been refurbishing slowly on my spare time. I love the sound and the design of the SFI Line 1/2/3. Here’s the issues I’ve had, some of which are similar to what folks have mentioned above. 1. Volume randomly maxing out: the preamp would randomly raise the volume to maximum, sometimes at power up, sometimes in the middle of operation. I found out that the problem was caused by a 74OL6000 optocoupler chip whose supply pins were not properly bypassed. This optocoupler is used to feed the digital signal from the front panel microprocessor to the Cirrus Logic CS3310 volume control chip. Per the manufacturer’s data sheet this optocoupler chip requires its supply pins to be bypassed with 0.1 μF or higher ceramic or tantalum capacitors. I installed 1 μF tantalum capacitors between the supply pins and ground and the problem has not returned (after a year and half). I believe this is a design flaw of this preamp as the manufacturer is quite clear about the use of bypass capacitors. 2. Preamp would power itself off randomly: the preamp would power itself off or power cycle itself randomly. This problem was due to a Talema 70051K transformer that is used in the Line 3 power supply for the low voltage digital circuits. In my experience, these transformers, which are used in 120 VAC units even though they are rated at 115 VAC, fail intermittently after about 20 years of use. Fortunately, these transformer’s exact replacement part is still available and I was able to replace it. Problem disappeared with this fix and has not recurred in a year and a half. 3. Headphone jack is loose: while working on the preamp I noticed that the front panel’s headphone jack would rotate if the headphone’s plug is rotated. This is not a good thing as there are metal surfaces surrounding the jack inside the unit and the metal pins of the jack are also exposed. This issue was solved by simply re-tightening the jack’s mounting nut on the front panel. However, this issue is likely to recur because the mounting nut is plastic and doesn’t attain a sufficiently high torque to fix it in place permanently. I need to add a metal nut and a locking washer to fix the jack solidly in place, then put the plastic mounting nut on top. I hope my experience is useful for folks on this thread. @jea48 |
- 13 posts total