Hello
The middle capacitor of the 5 is 10uf, why change it to 100uf, is it powering something?
There are many tube recommendations to be used on those Tube Preamps: Voskhod Rocket 6J1P-EV / 6ZH1P-EV, GE JAN 5654W and Voskhod Rocket 6J38P-EV / 6ZH38P-EV(bigger tubes with higher Anode Current and Transconductance. I'm using them right now)
I did tried lots of variation of capacitors in values, types, brands for these 9 caps around Opamp. I felt 100 uF improved the sound a bit. Also I am using 4.7 uF after OPA since even 1 uF MKT didn't cut the bass in any capacity.
Yes
I am using Voskhod 6J1P-EV on my diy tube pre. I will say try the Tube 03 without opamps. That will give you a much faithful tube character while being devoid of OPA amplification.
Yes.
I am using Voskhod 6J1P-EV on my diy tube pre. I will say try the Tube 03 without opamps. That will give you a much faithful tube character while being devoid of OPA amplification.
Well, that's why I have FX Tube 01 (opamp-less). But with no tone control. I was lucky to grab one while they were available.
If you remove the opamps on the Tube 03 and connect its (opamps) inputs to outputs you also lose the tone controls, right?
Absolutely.
Yes, Removing the OPamp brings the Tube 03 much closer to Tube 01. I personally don't like tone controls.
One OPamp is for volume while other controls bass and treble. So you loose both volume control & tone controls with both chips removed (as per what i have read, i dont own a unit).
I will love to have the FX Tube 01J variation, but Aiyima A03 is available here on amazon at a good pricing. Schematics looks similar to Tube 03.
What power supply do you use with the Tube Preamp?
A Linear Power Supply is highly recommended. A cheap Pyramid 5A PS 13.6V does a good job.
The idea is to feed the Tube heater at 6.3V, but there are diodes and transistors on the power section which bring the voltage down about 1 V. That Why a 13.6V Power supply provides the right 6.3V for the heaters.
I have a cheap diy tube pre. I am feeding it via a 13.2 V transformer.
Linear supply is mostly recommended but it wont necessarily mean we will always get a better result (very dependent on schematics).
Also on most of these kind of pre there is voltage doubling going on so that they can convert 12V input to +/-30V which will then feed ~60V to the tubes. This circuit is actually a smps in itself so even if you use linear power supply, its a combintion of both and not strictly LPS. Improvements can be had with power supply upgrade but will still be limited by the power circuitry that boost the voltage for tubes.
I have heard great things about Astron & Pyramid LPS , but again they are out of reach due to my current location.
I do usually check the tube heater voltage when i feel the tubes are glowing brighter. But mostly they are within their safe margin. I also do use Kemet A750 high ripple current polymer caps for filtering the 6.3v heater voltage. That insures a much smoother heater voltage the tube sees.
Also, a regulator is much preferred to a resistor that controls the heater voltage (mostly used on these kind of preamp). Hence eliminating the risk of uneven heater voltage for varied input voltage.
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Hello everyone. I upgraded my OPamp on my Aiyima A07 from stock NE5532 with OPA 1656, having read alot of good things about them. But i am very dissappointed. The sparkling high end details dissappeared while making the whole presentation very dull & boring. The audio feels much better overall with NE 5532. How is this possible. Am i doing something wrong ? Or are the 1656 chip supposed to have a burn-in time ?
Also, I have used 4.7uF electrolytic + 0.22 uF film cap across the OPamp power pins. But removing them doesn't improve the sound either.
Also, I have used 4.7uF electrolytic + 0.22 uF film cap across the OPamp power pins. But removing them doesn't improve the sound either.
I would recommend to remove the bypasses(which you already did). The new opamps brand new should be better than the stock "NE5532" which are probably fake(mine were). One question: where did you buy the opamps?. A trusted source like Mouser or Digikey is recommended. Could you share some close up pictures?
I bought these chips via mouser & have hand soldered them myself. I have rechecked all solder joints & everything looks as it should be.
Right now I have bypasses removed on them & waiting on how they will compare to NE 5532 after couple of days. It's just an hour old for now.
The sound is not bad actually but i don't feel it as an upgrade !
The sparkle is gone (i was fearing this since 1656 are considered bit warm & analogue-ish, but thats okay). But i sense a loss of detail as well
The sound now feels like its coming mostly from in between stereo speaker ( much constrained ), while wiith NE 5532 it feels like the notes are floating all over in the space between & outside the speaker.
It killed the lively sound and is now very polite which lacks musicality in my opinion. The hi-hats , percussions feel boring & not lively at all.
Should i expect them to improve over time (dramatically?) ? Or is it just that this OPAmp isn't synergizing well with the rest of my system ?
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Leave it running overnight at low volume. And compare them again tomorrow.I bought these chips via mouser & have hand soldered them myself. I have rechecked all solder joints & everything looks as it should be.
Right now I have bypasses removed on them & waiting on how they will compare to NE 5532 after couple of days. It's just an hour old for now.
The sound is not bad actually but i don't feel it as an upgrade !
The sparkle is gone (i was fearing this since 1656 are considered bit warm & analogue-ish, but thats okay). But i sense a loss of detail as well
The sound now feels like its coming mostly from in between stereo speaker ( much constrained ), while wiith NE 5532 it feels like the notes are floating all over in the space between & outside the speaker.
It killed the lively sound and is now very polite which lacks musicality in my opinion. The hi-hats , percussions feel boring & not lively at all.
Should i expect them to improve over time (dramatically?) ? Or is it just that this OPAmp isn't synergizing well with the rest of my system ?
Tomorrow, you can try this: use Foobar on your computer with a Mono add-on. And then use Windows Audio settings to change the balance between left and right channels. Being mono both speakers should sound the same, right?
On the Aiyima use one NE5532 on the left channel and one OPA1656 on the right channel. This way you can compare them quicker and note their differences and choose the best one for you. Then you can swap them and repeat the same test. Your selection should match with the location of your favorite opamp on both cases. You can run this test with the top cover removed for an easier access to remove the opamps.
I don't know if you have a opamp extractor, if not you can use one of those coated wires used to close the bread bags( or even dental floss) and place them underneath the opamp, between the socket and the opamp. This gives you a better grip to quicky remove them.
On these tests the key is in being quick to perform the changes.
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Yes thats the plan. Will play some burn-in audio & leave it for a fresh evaluation.
Sorry, I edited my previous reply after your reply. Try those test mentioned on my previous reply
Sure, will try & update. Meanwhile am contemplating to place the order for LM4562.
There aren't here many people not liking "quite a lot" OPA1656, and that in various configurations suited to his specs (say mainly what people consider standard FET equivalent use, be it pre amp, amp, RIAA amp... quite versatile and robust little OPA as long as considering implementation as one should).
This application suits OPA1656 idealy. We had though already one person, out of a few hundreds, reporting not being happy. That means 2 things in my limited eyes and I won't go further as I do consulting for a living and that would mean charging you if starting a debate :
1- Something is wrong with your OPA1656 set up. SMD soldering, socket, PS... whatever...
2- You like it biased and non neutral re sonic performance, funky or loudness effet hello, or whatever your taste... and I respect that. Admittely there are more 'typed' OPAs around that can give you the sound YOU like and the beauty of the socket is you can try many provided they are compatible for this location.
As said, I won't expand further, did that already and opened a can of worms with someone that had limited tech knowledge. Further, at the end, my comments don't matter : this is Audio DIY, your are tweaking, important is YOU are happy and comments from others, including mine, are just what they are.
Have fun
Claude
PS: hint ...have you ever soldered SMDs before and did you consider a quick reflow of the OPA's pins?
I AM OUT, REALLY LOL!
This application suits OPA1656 idealy. We had though already one person, out of a few hundreds, reporting not being happy. That means 2 things in my limited eyes and I won't go further as I do consulting for a living and that would mean charging you if starting a debate
:1- Something is wrong with your OPA1656 set up. SMD soldering, socket, PS... whatever...
2- You like it biased and non neutral re sonic performance, funky or loudness effet hello, or whatever your taste... and I respect that. Admittely there are more 'typed' OPAs around that can give you the sound YOU like and the beauty of the socket is you can try many provided they are compatible for this location.
As said, I won't expand further, did that already and opened a can of worms with someone that had limited tech knowledge. Further, at the end, my comments don't matter : this is Audio DIY, your are tweaking, important is YOU are happy and comments from others, including mine, are just what they are.
Have fun
Claude
PS: hint ...have you ever soldered SMDs before and did you consider a quick reflow of the OPA's pins?
I AM OUT, REALLY LOL!
Hi, I after all these mods I have lost the memory of how my A07 sounded in stock. I will give these elnas some good 100-150 hrs to settle in before making a judgment since NE 5532 still sounds better than OPA 1656 with those elna in place. If not happy after that too, i will try swapping those elna with Nichicon FG. I have also found a user comment on amzn Aiyima A07 page that reflects my similar experience.
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Ah, of course then there is a third option!
I completely forgot that you had a 07 and not a 04 and hence none of our posts in this entire threads is relevant! It can be... or not.
Sorry, my bad, thought 04... re 07 no clue, never had that unit! Who knows how it works, what schematic, or... what biase sound it may have and what mod to do to compensate for them. As, let's be honest, all of these cheapo amps sound great out of the box for the money, but none sounds like an ultimate amp IMHO.
Claude
I completely forgot that you had a 07 and not a 04 and hence none of our posts in this entire threads is relevant! It can be... or not.
Sorry, my bad, thought 04... re 07 no clue, never had that unit! Who knows how it works, what schematic, or... what biase sound it may have and what mod to do to compensate for them. As, let's be honest, all of these cheapo amps sound great out of the box for the money, but none sounds like an ultimate amp IMHO.
Claude