[bsd2000]

I just received my HA-160 today and it seems a little underpowered for my HD 650's and HD 800's. I tried both jacks and obviously the left one is louder, but not THAT much louder. Even cranked all the way up, it's less then what I would have expected from an amp of this caliber. It seems like it runs out of steam @ 12 o'clock and doesn't increase in volume much after that - all the way to max. I also tried my Grado SR 60's in the right jack and it's very low, the left sounds better with them too. I read reviews where they said anything above 9 o'clock is to loud, on mine, that's barely audible. I haven't tried it yet, but I couldn't imagine this powering my 600ohm AKG 240's to anything more then a whisper.
 
FYI: I'm using various sources - a Sony DVD-9000ES SACD/DVD player, Revox A77 reel to reel tape deck, Rega P25 turntable w/Zyx R100H cartridge and Audio Research PH5 phono preamp, Focusrite Liquid 56 firewire interface and a Presonus Inspire firewire interface. I also tried it with my Ipod Touch (using a headphone to RCA cable). I also have a Musical Fidelity X-Can v3 with 60's vintage Amperex 'Bugle Boy' 6DJ8's for comparison.
 
Does anyone else have the same problem? Is my amp defective?

 

[kwkarth]

How are you hooking this thing up?  Something is certainly wrong.  The HA-160 is a very powerful amp.

 

[bsd2000]

My main use is right after my phono preamp for critical listening. For recording LP's, I use the line output from my Presonus Inspire or Focusrite interfaces. The interfaces serve as my DAC. I don't have a traditional preamp or amp (or speakers) connected to my vinyl rig since I record them first @ 96k/24bit and store them on my server.
 
I spent more time listening to some vinyl through it and it's truely a mind blowing amp, especially with my HD 800's. It is loud enough to fully enjoy listening to it, but it's just kind of odd how the stepping on the attenuator doesn't have much more to give past 2 o'clock. I would say my X-Can is almost twice as loud overall. But, I must admit, the X-Can doesn't sound as good as the HA-160. The clarity and transparency is awe inspiring.  
 
I did notice the layout inside is slightly different then other pictures I've seen floating around. Mine has the transistors/regulators mounted underneath the PC board, bolted to the bottom of the case.
 
 

 

[kwkarth]

If I understand you correctly, you're not using a phono cartridge preamp?  What turntable and cartridge are you using?  Normally, you need a RIAA equalized phono preamp, whose output you would plug into the line in on your HA-160. 
 
So what's connected to what?

 

[stainless824]

mines is plenty loud- i noticed the loudness was different with the dac19 to the d4 lineout. Source I'm prepared to guess

 

[snaps11]

Mine is like this as well.  But anything past 10-11 o clock (hooked into my sound x-fi) is painful to keep on my head.  But using the right jack after 12 o clock it does feel like it doesn't get much louder.

 

[bsd2000]

 
Quote:

If I understand you correctly, you're not using a phono cartridge preamp?  What turntable and cartridge are you using?  Normally, you need a RIAA equalized phono preamp, whose output you would plug into the line in on your HA-160. 
 
So what's connected to what?

Here's my vinyl rig:
 
Rega P25 -> Zyx R100H moving coil cartridge -> Audio Research PH5 tube phono preamp (RIAA EQ) -> Burson HA-160 -> HD 650's and HD 800's.
If I want to record an LP, I insert my Presonus Inspire recording interface between the preamp and Burson, using the outputs from the Inspire to feed the Burson.
 
You can see and hear my turntable on Youtube: http://www.youtube.com/user/BSD2000
 
I've also used it with my Sony SACD player, Ipod Touch, and Revox A77 reel to reel.
 
I'm beginning to think that Burson changed the resistors in the volume control to have a softer ramp up; zero to noon on the dial, then a relaxed curve from there going up to full volume where the difference between noon and full is about 50% louder. Standard ALPS pots usually ramp up in a linear fashion where the difference between half and full is about twice as loud.
 
It's like having a car that you have to press the gas pedal 50% down for it to start from a dead stop. Then, once your going, flooring it makes it go just a little faster after that. 
 
If you look at the picture I posted and compare to other internal pictures other people have posted, they are different. It looks like Burson revised the HA-160; changing the mounting position of the transistors and even changing the values of the capacitors on the board. It leads me to believe they changed the resistor values in the attenuator to create the volume effect I'm describing.
 
Maybe the changes were made to address complaints that the volume was too loud for sensitive headphones and ramped up to early in it's range.

 

[kwkarth]

 

 
Quote:

Here's my vinyl rig:
 
Rega P25 -> Zyx R100H moving coil cartridge -> Audio Research PH5 tube phono preamp (RIAA EQ) -> Burson HA-160 -> HD 650's and HD 800's.
If I want to record an LP, I insert my Presonus Inspire recording interface between the preamp and Burson, using the outputs from the Inspire to feed the Burson.
 

Ok, that makes sense as long as your PH5 has sufficient gain and impedance for a moving coil cartridge, which usually requires an additional gain stage beyond what a typical moving magnet cartridge requires.  edit: Just looked up the specs to the PH5...Nice phono preamp!  Should be no problem with gain or loading/impedance match.
 
 
Quote:

I'm beginning to think that Burson changed the resistors in the volume control to have a softer ramp up; zero to noon on the dial, then a relaxed curve from there going up to full volume where the difference between noon and full is about 50% louder. Standard ALPS pots usually ramp up in a linear fashion where the difference between half and full is about twice as loud.

Interesting!  I will have to try to hear one of the new ones.
 
 
Quote:

It's like having a car that you have to press the gas pedal 50% down for it to start from a dead stop. Then, once your going, flooring it makes it go just a little faster after that. 

Depends upon the car.  If I did step one or step two with any of the past few cars I've owned, I would have gotten into a lot of trouble, very quickly.
 
 
Quote:

If you look at the picture I posted and compare to other internal pictures other people have posted, they are different. It looks like Burson revised the HA-160; changing the mounting position of the transistors and even changing the values of the capacitors on the board. It leads me to believe they changed the resistor values in the attenuator to create the volume effect I'm describing.
 
Maybe the changes were made to address complaints that the volume was too loud for sensitive headphones and ramped up to early in it's range.

The taper on a volume pot or on a stepped resistor bank used for volume control should be logarithmic in order for the user to perceive a nice linear progression of volume change. 

 

[JIGF]

     Quote:

 

That looks very different from this.
 

 

 

[classakg]

Quote:

How are you hooking this thing up?  Something is certainly wrong.  The HA-160 is a very powerful amp.

Definitely, it does have lots of power..It drives my Akg's without a problem. 
 

 

[carminedemaria]

i returned!have noise problem!

 

[MLee]

I also think they may have made some modifications based on the complaints of too loud too fast. I was expecting the volume at 9:00 to be as much as my W3000ANV would take but I can turn it up to 12:00 and it's loud but not over the top. I've noticed too that from 12:00 on the volume doesn't seem to increase at the same rate. I just got mine a couple weeks ago from HIDEF, the US distributor, so they could be a recent build. I do like the amp very much.

 

[zackzack]

From what I can gather, the Burson is one powerful amp. There must be something wrong with your set up

 

[MomijiTMO]

Nnnnnecroooo post

 

[Okamoto]

Mine doesn't go up from 2 o'clock to max as much as from zero to 2 o'clock either. However, I find it more than enough to drive my HE-400 to decent volume levels. I never get past 2 o'clock.
 
Sorry for necro'in this thread again btw.