Review: Aiyima T9, Part II
T9, Part I
Part II picks up loose ends, and took place in my less used Living Room, which had nonetheless been transformed by some recent arrivals, as detailed in my “New Trajectory” article. Since I published that, I have tweaked the system here and there, and it is increasingly satisfying, if not quite on the level of my primary system in the study but qualifying for somewhat more casual listening.
All Listening with the Anubris "LS3/5A"
It should be noted that the “LS3/5A” is less efficient than the Floorstanding Sansui in the study. In the latter, after significant revamping (here), I can get utter tube bliss with my APPLause 300B amp - no apologies, no if’s, and’s or but’s. Not quite so in the larger LR. As to whether this loudspeaker really replicates the legendary BBC sound, the answer is more complicated and shall have to wait for a later article.
As Integrated Amp with Anubis LS3/5A
The T9 did a very competent job, just as it did with my main loudspeakers in the study (see Part I).
As Preamp with Aosibao 6P1 PSE Amp
The T9 did, and still does, a good job as a Preamp, driving the 6P1 amp, which is likely a watt or two less powerful than the 300B amp now residing in the study. Compared to the T9, the 6P1 amp is audibly less powerful and on the soft side, but it is tonally opulent and graceful even when pushed to its limits (you hear it as a flattening of dynamics rather than outright clipping). This is a big room, but this tube man still chooses it despite its limitations (the 300B amp does even better but it is reserved now for the study). In this scenario, as with all low powered amps (SET or not) the contribution of the preamp becomes very critical. I shall have more coming in due time in this regard. In case you wonder how competent the T9 is as a preamp, let me inform you I also tested the tiny Xinyi (Sini) (here, and also in bottom pic) and, while it is a very competent amp, it fails utterly with its Aux Out as preamp. This shows you the Pre-Out of T9 is solid and not just a value-added thing.
Tube Rolling
As Integrated Amp with Anubis LS3/5A
The T9 did a very competent job, just as it did with my main loudspeakers in the study (see Part I).
As Preamp with Aosibao 6P1 PSE Amp
The T9 did, and still does, a good job as a Preamp, driving the 6P1 amp, which is likely a watt or two less powerful than the 300B amp now residing in the study. Compared to the T9, the 6P1 amp is audibly less powerful and on the soft side, but it is tonally opulent and graceful even when pushed to its limits (you hear it as a flattening of dynamics rather than outright clipping). This is a big room, but this tube man still chooses it despite its limitations (the 300B amp does even better but it is reserved now for the study). In this scenario, as with all low powered amps (SET or not) the contribution of the preamp becomes very critical. I shall have more coming in due time in this regard. In case you wonder how competent the T9 is as a preamp, let me inform you I also tested the tiny Xinyi (Sini) (here, and also in bottom pic) and, while it is a very competent amp, it fails utterly with its Aux Out as preamp. This shows you the Pre-Out of T9 is solid and not just a value-added thing.
Tube Rolling
Here we have some widely available cheap (latter day green letters) GE tubes that we can use. Mind you, the green lettered ones are abundant and the cheapest, but older variants are inevitably better sounding. The 5654 is not an exact 6K4 equivalent, rather that of the Chinese 6J1/Russian 6Ж1П /EF95/6AK5 (the latter available in much more expensive WE version, including even earlier 403A; should you really want to splurge a little, you may want to read about my considerable previous experience in the well-chronicled Yamamoto CA-04 Preamp, and, more briefly with the FX-TUBE-01). The 5654 confers a more textured sound, though the stock 6K4 is likely a little more open. Just recently, I was loaned the 5725 (in spec’s more akin to Chinese 6J2/Russian 6Ж2П; also WE 409A) and it is a different sound: more extended at either end, a little louder and seemingly more dynamic, though sometimes showing a slightly rough edge, which nonetheless seems to benefit some material; ultimately, I’d think the 5654 is more balanced and closer to the more neutral sound of 6K4, but do try the 5725 as it is ultra-cheap and fun (yes, I'm going to get my own pair too). For a very small outlay, tube rolling is fun. I’d not bother getting the Riverstone stuff - the premium can be better spent getting other older NOS or used variants.
USB vs BT
USB vs BT
By this round I had received a length of my favorite Unitek cable, this time USB A to B rather than the A to Mini I had long used with my Meridian Explorer. It took rather long to open up; in the end it sounds rather close to, but not quite the same as the A to Mini with adaptors (as detailed in Part I). Nonetheless, after running in, it’s obviously superior to the BT.
Power Supply
Power Supply
I only tested this with T9 as Preamp, but it makes a big difference. With a humble and cheap adjustable SMPS (around USD 4; rated 3A, lower left corner, on upper shelf, in top pic) I experimented with different voltages. The T9 specifies 18-30V, and the stock PS is 24V. I tried all voltages, but preferred the lower ones for more refinement, and I settled on 19V. As preamp, the T9 is warm to touch, and draws a steady 0.38 A only. Things took a significant leap when I switched to a somewhat more expensive, albeit still SM, PS (lower shelf in top pic and also bottom pic; around USD 30). More easeful and further refinement. My unit can go up to 30V and 5A, enough for more applications. Reassuringly, it also can cap voltages and currents, a good safety feature. IMHO, if you take home one message here, it’s that a good and still very cheap SMPS is a considerable improvement on wall warts. Don’t get hung up on expensive custom LPS. I have not tested its effect on the amp as a whole, but as a believer that the front-end is the most critical, I'm confident in my recommendation. Mind you, there are many to pick from; I just picked one that looks appealing to me.
There’s a lot more to say on the other stuff, but here’s not the place.
There’s a lot more to say on the other stuff, but here’s not the place.
Posts
I'm really enjoying the T9. My local tube store had the GE 5654 from 1966 in stock for 5€. The Loudspeaker I use is from Jean-Marie Reynaud the Bliss Jubile with Belden 9497 cable. Thanks for the tip.
ReplyDeleteYes, JMR makes decent stuff. 1966 GE is a lot better than the more available JAN GE's, which are from the late 80's. It's actually also worthwhile to give the 5725 a try - I'm growing fonder of it! Thx for chipping in.
DeleteAny reactions as yet to the T9 Pro? Looks to be a response to some of the criticisms leveled against the T9, and a significant aesthetic re-design, with slightly lower-profile tubes for the buffer stage. Would love to know what you think.
ReplyDeleteThe T9 Pro surely doesn't have the relay clicks that unduly bother some. That necessitated the use of a different chip, the more expensive Qualcomm. Since the chip and supporting circuit are different, the sound is too. A journal reviewer would tout the Pro as having an even lower noise floor and even cleaner sounding, but for me it has perhaps lost "just" a little of the enthusiasm of the original. Most may not even notice as it's very subtle. Perhaps this is also because I have lived with the T9 for much longer. I may yet write about it in '23.
DeleteCould you please send a link to the adjustable SMPS to klavikat@gmail.com (I can't find it and unable to login here). Thanks!
ReplyDeleteWait just a little while. I have been thinking of writing an article on PS's. Since you ask, I shall get it done within a few days. Check back at the blog. Thx.
DeleteWhat power supply would you recommend for the T9 or T9 Pro that can be purchased on Amazon or similar site in the US?
ReplyDeleteI'm convinced that these audiophile "experts", could care less about listening to music (which at one point involved simply hitting a play button), they just like plugging electrical things in, then giving their opinions on it, which are moot, because you aren't in the room with them when they're reviewing "said" amp/preamp/etc. So, let me get this straight.... The audiophile expert opinion on the cheap chinese product #500 floating around the internet is that "The T9 sounds great, but has X number of problems, and desperately needs a new "PS" (power supply I'm assuming) to get the most out of it. However, the T9 Pro has fixed the majority of "said" issues the T9 has, but no one knows if the power supply needs replaced. If it does need replaced, then, short of buying a variable power supply (SMPS...whatever that means), which costs more than the amp itself, no one knows which one, or where, to get it. And, if you do decide to get this "SMPS"....."thing", then you can just get a "good but cheap one" (again, whatever that means), then the T9 is great (but only if you use it as a preamp, in this case).
ReplyDeleteHonestly, sit back and listen to how you experts (whether that's regarding "cheap" equipment, or not), sound. It's beyond ridiculous.... If your kid came to you and described a problem like that, you have him medicated.
I think most SMPS (switch mode power supply) are alike. They are cheap. Just pick one that can go up to 5A. It's the extra current capacity that improves the sound of an amp. I think the make is not very important, standard technology. Give that so many gear use wall wart PS, an adjustable and current capable SMPS is useful. It even improves my DAC, which operates at a lowly 5V and drawing a mere 0.3A. Hearing is believing.
DeleteHere's my article on cheap PS:
Deletehttps://cheaptubeaudio.blogspot.com/2023/01/cheap-and-good-dc-power-supplies.html
Hi, I'm using the power brick that comes with the Aiyima T9 amp. It's a 24v. However it making buzzing noise, louder than usual. Is it fault of the adaptor. By changing the power brick would it made any difference. What is the power rating would improve quality of the amp. Thanks. DT
ReplyDeleteYes, some of these switch mode power supplies sometimes buzz. But louder than usual likely means u should change it out. Most don't make the noise. The T9 is rated to take up to 30V (even larger brick). Higher V would mean more available power but likely at the expense of somewhat coarser sound. If you have enough driving power, stick with 24V.
DeleteHi, can I use a cd player as a transport system and connect the toslink directly to the Aiyima T9. I tried and no sound. I changed the option to optical on the Aiyima. Thanks for interesting read.David
ReplyDeleteOf course you should be able to! I don't understand what's happening. If you are also using a coaxial cable, try removing that. Or try to disconnect the Bluetooth first. If you have another DAC, try connecting the CDP optical out to it and determine if it is functional.
DeleteWhy does T9 volume not return to zero after I turn it off? Do you have any solution? Thank you
ReplyDeleteI'm not sure what's the technical name, but this kind of rotary volume has no endpoint at either end. No zero volume. Nothing to worry about.
Delete