Aiyima T8 valve amp, to grease or not to grease...?

[Schlippwhip68]

I remember tubes from the 1960's and I even owned a couple of tube amps into the 70's. Tubes used to burn-out occasionally and maybe even come loose in the socket but I don't ever remember anybody "treating" the contacts.

I think its a bit of a novelty to some degree to be honest DVDdoug, a sort of nostalgic modern homage, but that said, it does work well with the T8.

 

[DVDdoug]

No offence but I don't agree with that at all. All equipment in my test is brand new and tubes are from a valid source, and the difference is cat and dog! There are very large audible differences as well as subtle in the sound from tube to other tube. Its also a widely agreed and known fact across the entire planet.

You know... Transistors & MOSFETs have "tolerances" too. But, usually the circuit is designed to be independent of these variations. Occasionally you might have a bias adjustment, but that's usually a one-time factory adjustment, or an adjustment if you have to replace a part. With tubes you might have to re-adjust the bias as the tube ages.

The same concepts CAN be used in a tube design, or it can be designed to behave differently with tube variations. IMO - A good design should be stable. ...I'll bet McIntosh tube amps don't change as the tube ages, or if you change tubes, as long as the tube remains within its specified tolerances.

Guitar amps are a different story. They are designed to have "tube sound" (not high
-fidelity) and they can be intentionally sensitive to tube swapping. Some "audiophile" amps may also be designed for "tube sound"... Also not high-fidelity.

 

[markzts]

I have not the tested the headphone yet but it is reported better than expected and even trumps the RCA at the rear of the T8 which in turn is vastly better than the D03 RCA implementation. Check Cheapaudiomans review of the T8 online. I would say this could be a good match for most class d amps. This is quite a loud combo T8/A8, I have a 5m x 5m room and going past half way say hitting 2 o'clock on the A8 and around 65 on the T8 is easily loud enough. The T8 goes up to 99 and I have not heard any distortion up to around 70. I have not pushed it any further as I have no need to. I was not convinced by the MA21070 at first but now i am eating humble pie and actually think it is quite impressive but imo...still a long way off good class A/B.
How is the sub on the D03 working out? The A8 also has sub out...
I am also a noobie with tubes like literally in the last week but the GE 5670 is vastly superior to the stock valve. The GE 5670 can be purchased at Watford Valves UK online and ebay for around £20.

I'm a cheapaudioman subscriber as well as some other tubers.

The sub out of the D03 has some noise on it, but it's above the bass frequencies and can be filtered out. I hardly ever use the sub out of any amps as I get what I want out of my mains.

 

[markzts]

I have not the tested the headphone yet but it is reported better than expected and even trumps the RCA at the rear of the T8 which in turn is vastly better than the D03 RCA implementation. Check Cheapaudiomans review of the T8 online. I would say this could be a good match for most class d amps. This is quite a loud combo T8/A8, I have a 5m x 5m room and going past half way say hitting 2 o'clock on the A8 and around 65 on the T8 is easily loud enough. The T8 goes up to 99 and I have not heard any distortion up to around 70. I have not pushed it any further as I have no need to. I was not convinced by the MA21070 at first but now i am eating humble pie and actually think it is quite impressive but imo...still a long way off good class A/B.
How is the sub on the D03 working out? The A8 also has sub out...
I am also a noobie with tubes like literally in the last week but the GE 5670 is vastly superior to the stock valve. The GE 5670 can be purchased at Watford Valves UK online and ebay for around £20.

I did find the D03 rca input to have less clear sound than the optical input/on board dac - as a result, I run my computer to the optical input and an old fm tuner to the rca input as that input quality fits the usage case. Good to hear the A8 rca input is better than the D03.

 

[Schlippwhip68]

I did find the D03 rca input to have less clear sound than the optical input/on board dac - as a result, I run my computer to the optical input and an old fm tuner to the rca input as that input quality fits the usage case. Good to hear the A8 rca input is better than the D03.

The RCA on both the T8 and A8 will not disappoint like they do on the D03. They are both clear. I never bothered with the RCA at all on my D03, thankfully the usb/opt/coax were all fit for purpose i.e PC and streamer.

 

[Schlippwhip68]

I'm a cheapaudioman subscriber as well as some other tubers.

The sub out of the D03 has some noise on it, but it's above the bass frequencies and can be filtered out. I hardly ever use the sub out of any amps as I get what I want out of my mains.

I haven't got the means to acquire a sub as of yet to test the sub out on the A8 but i did try my Topping e30 with it. It was razor sharp! Maybe too sharp but i did not let it run long enough as it was time limited. At this point at I could hazard a guess an say something like the SMSL Sanskrit MK2 dac could be a very good match for the A8 but then it would lose the benefits if the T8 like bass and treble control as well as Bluetooth..maybe there are not enough decent £150-ish capable stand alone dacs with bass and treble control at the moment..

 

[markzts]

I haven't got the means to acquire a sub as of yet to test the sub out on the A8 but i did try my Topping e30 with it. It was razor sharp! Maybe too sharp but i did not let it run long enough as it was time limited. At this point at I could hazard a guess an say something like the SMSL Sanskrit MK2 dac could be a very good match for the A8 but then it would lose the benefits if the T8 like bass and treble control as well as Bluetooth..maybe there are not enough decent £150-ish capable stand alone dacs with bass and treble control at the moment..

I have an fx audio d502bt - it has a lower power TAS series TI amp chip ( same series as D03 I think ). Anyway, it works fine on the digital, analog in, and the sub out. The D03 just sounds dull on the analog I/O. Again, I'm glad the D03 digital inputs are clean sounding.....

 

[Schlippwhip68]

I have an fx audio d502bt - it has a lower power TAS series TI amp chip ( same series as D03 I think ). Anyway, it works fine on the digital, analog in, and the sub out. The D03 just sounds dull on the analog I/O. Again, I'm glad the D03 digital inputs are clean sounding.....

Yep, the digital I/O on the D03 is very good and better than the same on the Loxjie A30 according to some but the Loxjie A30 has better RCA but that is not going to be difficult to do compared to the D03.

 

[markzts]

ended up getting an A07 to pair with the T8 and it all works great. I keep the A07 volume at max and use the T8 to control the volume with no noise issues - completely silent when it should be even with the T8 volume also at maximum.

One thing that is wrong on my T8, though easily corrected, is that the rca outputs are reversed left to right. The headphone output is correct, however.

 

[crack_squirrels]

Does the T8 support the AAC codec over bluetooth?

 

[fpitas]

Since no one mentioned using silicone dielectric grease, I will.

 

[JeffS7444]

Since no one mentioned using silicone dielectric grease, I will.

But as the name implies, that's a dielectric, not a conductive substance. I reserve that for spark plug boots on my car, in order to keep contaminants out, and keep the electrical energy from finding alternative paths to ground.

 

[fpitas]

But as the name implies, that's a dielectric, not a conductive substance. I reserve that for spark plug boots on my car, in order to keep contaminants out, and keep the electrical energy from finding alternative paths to ground.

It's also commonly used to pack connectors against moisture penetration etc. The shear strength is small, so it pushes aside as the connector is engaged.

 

[egellings]

But as the name implies, that's a dielectric, not a conductive substance. I reserve that for spark plug boots on my car, in order to keep contaminants out, and keep the electrical energy from finding alternative paths to ground.

A waterproof sealant, basically.

 

[Schlippwhip68]

Does the T8 support the AAC codec over bluetooth?

I think so...not to sure but another option in mind of which does have great bluetooth sound is the Aiyima T6 Pro preamp. I have the T6 currently wired into my A07 and the bluetooth is very good, sounds surprisingly good BUT I will have to add that i did change the op amps in both the T6 and A07 to a full set of Oracle 02 in both and i did not even bother listening to the stock op amps which in the T6 are Japanese Radio Company NE5532 and in the A07 Texas Instruments NE5532. I also swapped out the valves and replaced them with a pair of Mullards 8100 which gave a thicker more fuller sound than the stock Jan 5654 valves also smoother highs with the Mullards.

 

[Vespa]

Its quite an impressive combination. I have had this for a few days. I have to say I like a more anylitical approach to my listening pleasure which is where my Cambridge Audio Topaz AM10 and Topping E30 play a fine role. The T8 has a warmer less detailed leaning but apparently the stock valve is known for being muddy and it is advised from Watford valves UK to replace it with at least a GE 5670 which will in turn clear everything up and give an overall far better presentation.
The A8 is another egg altogether. I ran my Topping E30 with an Hama DTi2105SBTX Streamer as the source with Internet radio station and it was a completely different breed to the union with T8. Much more detailed and precise for the short time i had to listen. That is not to say that the T8 is worse because it is not, it is a warmer sound and to many ears will be easier to listen to for longer periods of time. I have not ran extensively into a listening test but I can say neither one of these two offerings from Aiyima are being sent back for a refund. There is plenty of room to play here.

Hey, thanks for this, I was seriously thinking about sending this back, purely speaking about my tests using it as a headphone amp it was veiled/muddy, but with the valve swapped out with a GE 5670 I can hear things like vocals much better. I have no experience with Tube amps of any kind but I'm enjoying the smooth sound. Looking forward to testing how this sounds with my A07 next.

 

[Schlippwhip68]

Hey, thanks for this, I was seriously thinking about sending this back, purely speaking about my tests using it as a headphone amp it was veiled/muddy, but with the valve swapped out with a GE 5670 I can hear things like vocals much better. I have no experience with Tube amps of any kind but I'm enjoying the smooth sound. Looking forward to testing how this sounds with my A07 next.

I think you might be able to fit a Mullard ef95 (5654) 8100 in there too if you want even better bass and clear stronger vocal range. The A07 is very well complimented with a tube preamp. I use an AIYIMA T6 Pro with my A07 with the Mullard Valves and it sounds better than my old Denon PMA720AE amplifier.

 

[Chrispy]

Grease? Tubes? No thanks!

 

[Schlippwhip68]

Grease? Tubes? No thanks!

No, I never bothered either.

 

[Chrispy]

No, I never bothered either.

This level of tweakery is just weird to me.