[I.Greyhound Fan]

When you get the amp, before playing music, give it a couple of minutes to fully charge the capacitors.  Make sure the standby switch is off when you plug it in.  Do all your connections first before plugging it in.  You will find that it sounds better after about 30 minutes of play time.  It is subtle but noticeable. 

Let us know how you like the amp.  Enjoy!

[JackD]

SoundSound

If you are still considering a balance tube preamp to go with the Pass amp take a look here of the Trading Post.

http://www.audiocircle.com/index.php?topic=149871.0

[SoundSound]

Thank you very much guys! 

Having a brain freeze... 

@I.Greyhound Fan: Did I get it correctly? 
1. Make all connections
1. Standby switch is OFF
2. Main power switch is OFF
3. Plug amp into the wall
4. Main power switch is ON
5. Standby switch is ON
6. Wait for 2 minutes
7. Play music (finally!)

What is the sequence for powering the amp down? 

@srb: Ordered! 

@JackD: Frankly, I am not sure if I should go with Tubes or Solid State preamp in case of XA30.5... But the price for Modwright 36.5 preamplifier is very tempting! 

[JackD]

My vote is always going to be tube preamp with SS amps.  Another great option in that realm though hard to find used is the PS Audio BHK Preamp.  Also a lot more new.  Also at that price for the Modwright if not you thing turn it back over. I am currently running the Modwright LS-100 with the PS Audio BHK amp.

[RDavidson]

ALWAYS turn your amp on last, and ALWAYS turn it off first. I once made the mistake of turning off my direct coupled tube preamp off before I turned my amp off. Fried my woofers. Good thing the drivers were relatively cheap and easy to replace. This was a long time ago and several systems ago...long prior to my "education" on AudioCircle. Live and learn.

[RDavidson]

My vote is always going to be tube preamp with SS amps.  Another great option in that realm though hard to find used is the PS Audio BHK Preamp.  Also a lot more new.  Also at that price for the Modwright if not you thing turn it back over. I am currently running the Modwright LS-100 with the PS Audio BHK amp.

With an amp as pure and colorful as the XA30.5, I don't think a tube preamp is a necessity moreso than a preamp that is transparent. I've never heard the Modwright, but know it is excellent gear.

[I.Greyhound Fan]

The Modwright is a good preamp.  I looked into buying one when I bought my BAT.

SS, no special procedure when turning off the Pass.  Just turn off the amp first, then your DAC  if you use one and preamp last.

[G Georgopoulos]

Dear Audiophiles! 

I am looking for a power amplifier with balanced circuit topology to replace Acurus in my modest Hi-Fi setup:
 
Mac mini (USB3 output) -> Singxer SU-1 ->
Yggdrasil DAC (AES/EBU XLR input) ->
Primare PRE30 preamplifier (AES/EBU XLR input) ->
Acurus A250 power amplifier (RCA input) ->
Monitor Audio RS-6
 
Any info/advice is very much appreciated. Please chime in! 

P.S. I am considering Lindell AMPX power amplifier, but not sure if it is a true balanced/differential design…

The term balanced here needs to be clarified (i don't get it)

1 - balanced inputs
2 - fully symmetrical amp topology
3 - bridged topology
4 - other

thanks

[RDavidson]

GG, the OP wants a balanced (dual differential) amp. I think we've covered that, and something tells me you know this too. We also know you don't like Class A amps due to power consumption. So......let's keep the thread moving forward versus going off on an unnecessary tangent.

[srb]

The term balanced here needs to be clarified (i don't get it)

OMG.  You QUOTED SoundSound's original post where he said he wanted an amplifier with true balanced differential circuit topology.  No clarification is needed.

Then in his reply #79 he let us know that he ordered the Pass XA30.5 and expected delivery this week.

I'm having a hard time understanding what your motives could possibly be. 

[RDavidson]

Hmmmm....let me guess a motive : To thwart the OP's plan to buy a class A amp (and a great one at that), perhaps? ugh

[G Georgopoulos]

Hmmmm....let me guess a motive : To thwart the OP's plan to buy a class A amp (and a great one at that), perhaps? ugh

no no,misunderstanding,i just wanted to educate you to what a fully balanced amp involves,take a look at the schematic bellow



it's a pass schematics, from what i have seen, pass incorporates balanced input in most of his amps
,this to some people is true balanced too believe it or not,i have been told so
,so you can see the misunderstanding,anyway i was going to educate you on more benefits of xlr,but
lets not derail your thread again,thank you and cheers..

[RDavidson]

One doesn't need to know how the engine in a Ferrari works in order to appreciate driving it. There are plenty of technical threads here on AC for those who wish to be educated on such things. Feel free to start one. This isn't the place.

[SoundSound]

@RDavidson: "ALWAYS turn your amp on last, and ALWAYS turn it off first."

Not sure how this works in case preamp and amp connected with the trigger cable I was bugging you guys about... In my understanding, when I turn my PRE30 to OPERATE from STANDBY it simultaneously turns the amp to OPERATE from STANDBY, and when I turn my PRE30 to STANDBY from OPERATE it simultaneously turns the amp to STANDBY from OPERATE.

What am I missing here? Should this remote link be employed at all?

Do I understand correctly, main power switch on the back panel of XA30.5 should ALWAYS be ON? Could somebody please estimate the power consumption of XA30.5 while in STANDBY mode?

As I mentioned earlier, am having a brain freeze… Sorry…

What solid state preamp with balanced circuit topology would you recommend me to consider, please? Preferably, below 3K used.

[srb]

Could somebody please estimate the power consumption of XA30.5 while in STANDBY mode?

Per the XA30.5 Owner's Manual, "When not actually intending to play music the amplifier should be left in standby mode, where it draws only a few watts of bias on the output stage."

Pass doesn't give a numerical standby power consumption spec, but most people take "few" to mean 2 or 3.  While there is no exact definition for "few" (more than 1, but not many), I generally expect it to mean not exceeding 5.

Steve

[SoundSound]

Thank you very kindly Steve! 

Anybody on the "trigger" confusion, please? 

Sitting on the needles: should be delivered today...

[srb]

I'll weigh in on the trigger topic.  While RDavidson gives good advice about amplifier power sequencing, it also depends on the equipment.  Some components have built in muting delay and they also differ in turn-on and turn-off transients and power supply charging and discharge.

While it's possible that some scenarios could damage a driver, I probably would personally give the trigger a try.  If turn-on and turn-off noises are subtle, I would use the trigger.  If they are not subtle, then I would revert to manual power sequencing and ditch the trigger.

It obviously works in many scenarios or Nelson Pass wouldn't have provided the trigger connection.

Steve

[I.Greyhound Fan]

I don't know if the 30.5 amp is like my X250 but I suspect it is.  It takes about 10 seconds for the Capacitors to discharge the stored power after I turn off my Pass amp.  Once my son  accidentally turned off my amp when music was still playing and the music continued to come through for about 9-10 seconds.

[brj]

Per the XA30.5 Owner's Manual, "When not actually intending to play music the amplifier should be left in standby mode, where it draws only a few watts of bias on the output stage."

Pass doesn't give a numerical standby power consumption spec, but most people take "few" to mean 2 or 3.  While there is no exact definition for "few" (more than 1, but not many), I generally expect it to mean not exceeding 5.

See my earlier post in the thread:

http://www.audiocircle.com/index.php?topic=149931.msg1605883#msg1605883

[srb]

See my earlier post in the thread:
http://www.audiocircle.com/index.php?topic=149931.msg1605883#msg1605883

I'm not saying that's excessive standby power consumption necessarily, but if it is 15W standby, it is poor product copy in that by no one's definition is 15W a "few" watts and Pass should just publish the numerical spec.

Steve