I’m fixing a Studer CD player I have. The disc motor does not spin and I believe IC7 is bad which is an RC4559, it looks like they’re only using one of the internal amplifiers.
I was looking through my stash and was curious if these would work in this circuit. Not sure if it’s less or more critical to match specs here than an audio circuit.
I have BA4560, JRC 4558 (the 4559 looks to be right between these two, just different manufacturers???), and then lastly TL072CP. I know the last one is a jfet design, but I’ve read it can be used as a replacement in some circumstances.
Any help with this would be greatly appreciated.
Dan
I was looking through my stash and was curious if these would work in this circuit. Not sure if it’s less or more critical to match specs here than an audio circuit.
I have BA4560, JRC 4558 (the 4559 looks to be right between these two, just different manufacturers???), and then lastly TL072CP. I know the last one is a jfet design, but I’ve read it can be used as a replacement in some circumstances.
Any help with this would be greatly appreciated.
Dan
Hello Dan,
Sorry for late reply, I only noticed your post when browsing through the Parts forum.
About swapping of RC4558 and RC4559, these two op-amps are pin compatible, with the RC4559 having slightly higher performance, but unless it's a critical circuit I think either one would work.
To share my experience, I did the reverse that is changing out the original installed RC4558 op-amps in my ReVox B790 turntable with the newer RC4559 type.
Details are described in my report, "ReVox B790 Turntable Erratic Speed Control - Hints & Lessons Learned" posted on the Audio Karma site.
https://audiokarma.org/forums/index...-speed-control-hints-lessons-learned.1025346/
As mentioned in the report I quoted from the ReVox service notes.
ReVox Service note 67.17 for the B790, Op-amp RC 4558 unsatisfactory.
The op-amp RC 4558 (made by Raytheon) has shown to have an excessive failure rate. For this reason it will be replaced by the high performance type RC 4559 / 50.09.0107 (-----). This op-amp is used in the following circuits 1.179.150/152.
I don't think there was anything wrong with the performance of the original RC4558 for the motor control circuit, although ReVox say they experienced failures with an early batch of the RC4558s and that was their reason for changing to the RC4559 type.
Just a detail, should you decide to replace your original RC4559 with new, if you look at the photo I posted in the report, "Figure 2. Motor Control board showing the four 4558 Op-Amps replaced by newer 4559" you can see these new op-amps are identified by the labeling "JRC 4559DD" where "DD" indicates the lower noise version of the RC4559 series. The lower noise version isn't a requirement for the motor control circuit, just that the "DD" version was about the same price as the standard RC4559 so that's what I purchased.
Hope this can help with the repair of your Studer CD player.
Thanks,
John
Sorry for late reply, I only noticed your post when browsing through the Parts forum.
About swapping of RC4558 and RC4559, these two op-amps are pin compatible, with the RC4559 having slightly higher performance, but unless it's a critical circuit I think either one would work.
To share my experience, I did the reverse that is changing out the original installed RC4558 op-amps in my ReVox B790 turntable with the newer RC4559 type.
Details are described in my report, "ReVox B790 Turntable Erratic Speed Control - Hints & Lessons Learned" posted on the Audio Karma site.
https://audiokarma.org/forums/index...-speed-control-hints-lessons-learned.1025346/
As mentioned in the report I quoted from the ReVox service notes.
ReVox Service note 67.17 for the B790, Op-amp RC 4558 unsatisfactory.
The op-amp RC 4558 (made by Raytheon) has shown to have an excessive failure rate. For this reason it will be replaced by the high performance type RC 4559 / 50.09.0107 (-----). This op-amp is used in the following circuits 1.179.150/152.
I don't think there was anything wrong with the performance of the original RC4558 for the motor control circuit, although ReVox say they experienced failures with an early batch of the RC4558s and that was their reason for changing to the RC4559 type.
Just a detail, should you decide to replace your original RC4559 with new, if you look at the photo I posted in the report, "Figure 2. Motor Control board showing the four 4558 Op-Amps replaced by newer 4559" you can see these new op-amps are identified by the labeling "JRC 4559DD" where "DD" indicates the lower noise version of the RC4559 series. The lower noise version isn't a requirement for the motor control circuit, just that the "DD" version was about the same price as the standard RC4559 so that's what I purchased.
Hope this can help with the repair of your Studer CD player.
Thanks,
John