Cayin A88T break in and biasing??

Hi Aball & Newbee,

Thanks for the reply's so far. Aball, The $1000 I will
have to spend is not for the tubes, but the difference
between it and the Jolida I took back to my local dealer.

BTW, My comments were based upon owners reading of the manufacturer's actual manual on your amp, not on the statements by dealers that they were auto-biasing. To clear up any conflict between two opposing posts I would suggest you obtain and read the amps manual. You might look at all of the various comments that a Google search can provide which includes professional reviews as well as user comments.

This amp is NOT AUTOBIASING. I owned a Jolida 302 also and now the a88t and it needs at least 10 hours breakin before sound improves.

Here's the biasing instructions graciously provided to me by another Cayin owner:

"Unless you swap out tubes, you do not need to bias the amp more than once every few months. Anytime you change tubes however, you must re-bias.
If you can go to the Acoustic Sounds web site and enter Cayin in your search...you will find the A-88T and can click on that model. Then find hi-res pics that show the underside of the amp and it’s circuits. It will be a big help if you can look at the picture on the Acoustic Sounds site before you start to see “what’s what”.
Be careful of course when doing this. Be certain the amp is turned up on its side (supported by something) - The amp needs to be up on it's side and plugged in, but no interconnect or speaker cables should be connected- it should just be plugged into the wall....

Okay, the directions:
You will see under the tube sockets where the wires are soldered. You will
also see the blue plastic pots (with screwdriver slots on their tops) next
to the sockets.

You want to use the blue wires on the front two Kt-88 (front of amp) and
use the Orange wires on the rear two Kt-88's as your + test points. They
are the only wires that are single wires on the sockets and have a double
solder connect. The second soldered connect (with NO wire attached) is the
test point for the + Positive probe of your multi-meter...The - Negative
test probe attaches to any black (- neg.) speaker terminal on the rear
binding post. Doesn't matter which one.

The test point is 0.4V or 400mV on your meter. Make sure to set it for
Volts or mVolts DC- NOT Amps or Voltage AC. I use a Sperry DM 4100A
meter purchased from Home Depot or Lowe's.

This may seem a bit confusing. But if you pop the bottom cover, you'll see
the KT-88 sockets from the bottom- then locate the Blue (front of amp) and
orange wire (rear of amp) and you will also see the 4- blue plastic pots for
adjustments. One by each tube socket. It won’t take much turning to find
the 0.4V...Adjust slowly with the probe on the test point and you'll see that.


Allow it to warm up for about 10mins before checking the bias. After
you've made the initial adjustments, wait 10 mins. and check again for drift.

They will settle a bit, but not a lot. You can fine adjust at this point"

Having said that, don't judge your amp untl you get it some time to really burn-in or perhaps tube role.

Hello Bonger,

Thanks, and you are exactly right! I called VAS to
leave a message, but they answered and told me that exact
same thing so now it can be put to rest. But it is
unfortunate for me, as I do know how to bias, but do not think
I want to go through that hassle. Sad they could not
put bias pots on the top or at least the side!?!?
It is starting to sound great though. I will have to give it
some thought the rest ofthe weekend.

Thanks to all!

Happy New Year!

Bob

I have noticed that , with My Cayin 88T , It took a while to get into the swing of things .
Even after turning it on to warm-up , for 30 - 60 minutes , it would sound 'off' until it had actually played for another 30-60 minutes .
Because this is my first foray into tubes , I don't know if it is typical .
I A/B it with a Cary Sli-80 and did not hear enough of a difference to justify the difference in price . They were really quite similiar . I enjoy the Cayin .
I do not believe it to be plug-and-play .