I made the adjustment as you stated in post#18. As I only have two hands I had to adjust pot, then measure. On the third try I had 36.4mv at test points. As touchy as the pot is, I called that good. Went to the other channel and after a couple tries I had 36.2mv. Waited a few minutes and measured again to ensure setting; AOK so buttoned her up. Listening now and it sounds good.
I read about this amp running hot. Mine is just warm after an hour or so. Maybe I need to listen louder.
I read about this amp running hot. Mine is just warm after an hour or so. Maybe I need to listen louder.
The low bias level suits a design like this one. The exact bias level isn't really as critical as theory suggests. +/- 5mV will still be be fine for a 35mV bias spec. Many components, particularly adjustable ones like trimpots, drift over time and with heat cycling anyway. Don't replace them with cheap import types if you plan to tweak things regularly like some audio enthusiasts seem to. 'better to leave them be until you can buy the real deal from an authorized parts distributor.
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Thanks. Are you able to send a little more detail - ideally, are you able to send the schematic?
I have an Elicit-R that needs these adjustments, and I'm competent with electronics, so just need a few pointers on where to measure and where to adjust. Thanks very much.
I did not find the plans on my storage stick, and due to company holidays I can not inquire,
send me a pm in ten days when I forget to add the schematic later.
send me a pm in ten days when I forget to add the schematic later.
Thanks so much! I'm away for a couple of weeks right now and will have a go at this when I get back. I'll post an update if there's anything useful to report.
Hi all.
The attached schematics in this thread (above) are interesting and no doubt helpful for those who know what they are doing !.
I note the description on both schematics is "Mira 2012 Elex \ Mira 2010". There's no mention of the Elicit ...
So, are these schematics correct for the Elicit-R Mk4 amplifier released circa late 2013 ?
Many thanks,
Pete
The attached schematics in this thread (above) are interesting and no doubt helpful for those who know what they are doing !.
I note the description on both schematics is "Mira 2012 Elex \ Mira 2010". There's no mention of the Elicit ...
So, are these schematics correct for the Elicit-R Mk4 amplifier released circa late 2013 ?
Many thanks,
Pete
As far as I know the schematics are the same. These have been sent to me
for said model by the local distributor and the file names are in fact Elicit-R.
for said model by the local distributor and the file names are in fact Elicit-R.
Hi, Thanks for your info & quick reply.
I was just slightly confused because the circuit diagrams state Elex / Mira.
Presumably the Elicit-R, Elex and Mira won't all use the same circuit diagrams ??
I was just slightly confused because the circuit diagrams state Elex / Mira.
Presumably the Elicit-R, Elex and Mira won't all use the same circuit diagrams ??
Thanks so much to as_audio. I have now finally had time to make these adjustments to both L and R - and the amp is SO much cooler now. Here are my notes in case it's useful for others:
Rega Elicit amp - bias adjustment
Warning: do this at your own risk - noting for example that mains voltage is exposed once you remove the lid. You’ll need an avo. If you don’t know what “avo” and “pot” mean, this isn’t a project for you! Many thanks to as_audio on diyAudio for the information needed to work this out.
Remove the 6 allen screws on top lid. Slowly lift lid, carefully removing earth connector (attached to its underside) before fully taking lid away.
Looking into amp from standing in front of it, the Left side of the circuit is on the right - see photo. You can see adjustable pot PR4 and two measuring points J25 and J1 (partly hidden). It is hard to get measuring probes to touch J25 and J1 without also touching other things, so put tape around any exposed metal on your probes except at the very tip.
Measure the DC voltage between the two measuring points. Adjust the pot until the voltage difference (between the two points) is close to 35mv.
Now do the same on the left side of the board (J23, J24, PR3). Note that J23/J24 are not in exactly mirror positions of J1/J25.
Rega Elicit amp - bias adjustment
Warning: do this at your own risk - noting for example that mains voltage is exposed once you remove the lid. You’ll need an avo. If you don’t know what “avo” and “pot” mean, this isn’t a project for you! Many thanks to as_audio on diyAudio for the information needed to work this out.
Remove the 6 allen screws on top lid. Slowly lift lid, carefully removing earth connector (attached to its underside) before fully taking lid away.
Looking into amp from standing in front of it, the Left side of the circuit is on the right - see photo. You can see adjustable pot PR4 and two measuring points J25 and J1 (partly hidden). It is hard to get measuring probes to touch J25 and J1 without also touching other things, so put tape around any exposed metal on your probes except at the very tip.
Measure the DC voltage between the two measuring points. Adjust the pot until the voltage difference (between the two points) is close to 35mv.
Now do the same on the left side of the board (J23, J24, PR3). Note that J23/J24 are not in exactly mirror positions of J1/J25.
Attachments
That's a great post and very interesting.
Having made your adjustments, has it made any difference to the sound ?
Having made your adjustments, has it made any difference to the sound ?
Hi everybody,
i need some help with my Elicit R. It usually took for about 5 seconds to activate the amp speaker relay. Now when i power up the amp for the first time in the day, it can take up to 20 minutes. Later, when the amp is warmed up, it seems to work ok again.
Anybody has some ideas what could cause this?
Thanks!
i need some help with my Elicit R. It usually took for about 5 seconds to activate the amp speaker relay. Now when i power up the amp for the first time in the day, it can take up to 20 minutes. Later, when the amp is warmed up, it seems to work ok again.
Anybody has some ideas what could cause this?
Thanks!
I can not open the file at the moment, but suspect a single capacitor. PS :
I see the schematic is already seen here, the place to look at is in post 29,
but I am too tired to give any advice now.
I see the schematic is already seen here, the place to look at is in post 29,
but I am too tired to give any advice now.
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Still have the same problem, but now i have some time to look into this. I have tried replacing capacitors C129 and C130 in the power amp section, but it did not make any difference.
At DC IN L/R test points i have around 44/91 mV. I do not think that something is coming from pre-amp section, as i have around 0 mV at RPWRIN/LPWRIN points.
I would appreciate some help, i could not understand which capacitor in preamp schematic(post 29) could be a problem.
At DC IN L/R test points i have around 44/91 mV. I do not think that something is coming from pre-amp section, as i have around 0 mV at RPWRIN/LPWRIN points.
I would appreciate some help, i could not understand which capacitor in preamp schematic(post 29) could be a problem.
Do you have some different drawings than ones posted here? I saw them on PCB but not in drawings.