Aiyima T20 Fully Balanced Tube Preamp, AKA Why do I do this to myself?

Jon L and 4 Guests are viewing this topic. Read 6416 times.

viggen

Can anyone confirm the DC input barrel size is 5.5 x 2.1mm? 

Jon L

Can anyone confirm the DC input barrel size is 5.5 x 2.1mm?

Can confirm.

Jon L

Now both the Aiyima T20 tube preamp and Douk A5 amp are powered from batteries  :thumb:




viggen

Can confirm.

Thanks.  Ordering a cable from Ghent.

viggen

Now both the Aiyima T20 tube preamp and Douk A5 amp are powered from batteries  :thumb:




Do you now prefer A5 over FU amp?

Jon L

After all the mods and dust settle, I'll have to do some serious comparisons..

FullRangeMan

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Look forward to see your impressions.

Poultrygeist

A few years ago I had fun with the very inexpensive FX tube preamps ( not buffers ). When I replaced the stock wall wort with a $35 Pyramid PS-3KX linear regulated power supply I noticed a significant improvement in SQ. The positive and negative power wires I ran through the holes in the Pyramid and exited out the back using a barrel connector adaptor to the FX.




Poultrygeist

These barrel adaptors make an easy job of connecting external power supply wires. These are the male version but they are available as female. 




Jon L

OPA828 opamp is a highly-regarded JFET-input opamp that usually comes in SOIC configuration, and two are needed per adapter for dual opamp duty. 

Its sound is different from most all monolithic opamps in that it really sounds like water, no real flavor to speak of.  This can be a very good or not so good thing depending on what one is trying to accomplish in the overall system sound.  Usually, modern, high-speed opamps tend to impress first but become somewhat tiring with prolonged listen, which OPA828 seems to avoid. 

Comparing OPA828 to OPA2604, which was felt to synergize well with Aiyima T20, was an illuminating experience.  If one assigns OPA828 sound as neutral, OPA2604 seems to synergize well with certain components due to its seeming effect of moving a tiny bit of upper-midrange to low-treble energy to high treble, which results in very airy sound with a degree of forgiveness in the hot-recorded upper midrange.  This can be very pleasing with many digital sources and class-D amps.  OPA828 fights back with more information and neutrality in that upper-midrange to low-treble, minus extra airiness, making music more solid and textured in that area. 

Definitely worth checking out both OPA2604 and OPA828 in a given circuit, as one is likely to be more synergistic than the other  :thumb:



« Last Edit: Yesterday at 12:43 am by Jon L »

viggen

I have the OPA134PA I bought by mistake. You got me tempted to get an adapter to fit two of these into the T20.

Jon L

I have the OPA134PA I bought by mistake. You got me tempted to get an adapter to fit two of these into the T20.

I ordered single-to-dual DIP8 adapters to try OPA627x2 in the dual slot. 


Jon L

Same one I ordered.  Let's hope it's sturdy. 

viggen

it really does sound like water.  i think i prefer it over muses02 atm.  it's not as soft sounding as muses02 yet more easy to listen to.  very clean and very balanced.  and your opa828 is supposed to be better than my opa134pa according to google ai:

Quote
The OPA828 is a higher-performance, lower-noise, faster, and wider-bandwidth op-amp compared to the OPA134, which is a legacy op-amp known for its excellent audio quality and ultra-low distortion.

edit: just ordered this on ebay
Quote
[AudioJade] TOP Grade OPA828 V5 Mono to Dual Operational Amplifier HiFi Audio
« Last Edit: Today at 02:54 pm by viggen »

Jon L

LOL, received the dreaded "Delayed, not yet shipped" message from Amazon.  Who knows when it will show up.

As a consolation, I now have the Opamp decoupling adapters with capacitors. 






viggen

when does the madness end?  is that a sparkos brand?  i don't see it on their site.

i can only find this one
https://www.creationaudiolabs.com/rock-it-socket?srsltid=AfmBOopHlUIIYCzFRsfJ-4ty1Lzm6wovBsJzMbzMXt4T1G0V31V4oN2Z

Jon L

when does the madness end?  is that a sparkos brand?  i don't see it on their site.

i can only find this one
https://www.creationaudiolabs.com/rock-it-socket?srsltid=AfmBOopHlUIIYCzFRsfJ-4ty1Lzm6wovBsJzMbzMXt4T1G0V31V4oN2Z

These are not just adapters.  Their purpose is to add additional capacitors to decouple the opamp power pins further, with reported benefits.  Unfortunately, they are rather expensive.

https://www.aliexpress.us/item/3256808610142833.html?spm=a2g0o.order_list.order_list_main.11.2fc71802I3w90H&gatewayAdapt=glo2usa#nav-description

viggen

might be cheaper to get one of these then you only need one decoupler for the t20
https://www.ebay.com/itm/355616376599

the rockit socket is also a decoupler with capacitor and only $5 tho the one you have is probably better because it has bigger capacitors haha

let us know if you here a positive diff with the decoupler.

Jon L

the rockit socket is also a decoupler with capacitor and only $5 tho the one you have is probably better because it has bigger capacitors haha

I wish.  Looks like one has to buy and solder the SMD capacitor himself, but moreover, rockit only allows one single-channel opamp for the capacitor to work :)