[jvh]

I have owned the HA-1 for a couple of days now. I ma using it with the stock tubes in place. My source is a dedicated Sony DVD-S9000ES with direct connection.

The amp starts distorting at about 10 o'clock on the volume dial and becomes excessive before reaching 12 o'clock. The volume is not that loud before distortion begins.

I moved the amp to one of my other systems with different interconnects. and the results are the same.

Is this normal for this amp or is something defective?

I can drive my HD-600's to way beyond comfortable listening levels with my MG Head out of the OTL jack with no perceived distortion. Or is this even a comparison?

John

 

[daycart1]

Huh? There is definitely something wrong! Do you have different tubes to try?

 

[jvh]

No I do not have any replacement tubes to try. I was thinking about ordering some.

I purchased the unit from HeadRoom. I will give them a call and see if they will exchange the unit. I thought the unit might settle down after a few hours of use.

John

 

[grinch]

direct connection? did you have mods done to your unit so the source has a volume knob? if so, turn it down! and before returning your unit, try it with another source; doesn't matter what it is, cdp, pcdp, dvd player, anything. this will make sure it is in fact busted or not.

either way, i hope you get this fixed!

 

[DanG]

I think it's possible that the contacts inside the headphone jack might be dirty. Try plugging/unplugging your headphones multiple times and see if that works.

It is also possible that it's the CD player, though if it works fine with the MG Head that shouldn't be the problem. However, the Wheatfield HA-1 was designed for lower-impedance headphones rather than higher-impedance headphones like the HD600. I doubt this would result in distortion, though.

Thirdly, as mentioned before, it could be a tube issue. I'd suggest you try it with a different souce as grinch suggested and to try plugging/unplugging your headphones several times and listening again. If neither works, I think you might have to send the unit back to Headroom.

 

[jvh]

Quote:

direct connection? did you have mods done to your unit so the source has a volume knob? if so, turn it down! and before returning your unit, try it with another source...

No modifications to the DVP-S9000ES. When I tested the amp in my other system the only thing that moved was the HA-1. It was tested with a new source and new interconnects.

Quote:

I think it's possible that the contacts inside the headphone jack might be dirty. Try plugging/unplugging your headphones multiple times and see if that works.

This did not work either.

I just spoke with HeadRoom and they are sending me out a replacement unit.

John

 

[fredpb]

Both channels?

 

[jvh]

fredpb,

Yes the distortion problem was in both channels.

My new replacement HA-1 arrived late this afternoon. Problem rectified.

Now to put some hours on the amp.

John

 

[jvh]

The HA-1 uses a new production JJ/Telsa ECC83

Would this TELEFUNKEN 12AU7/ECC82 be a good selection for startup rolling?

Can I use a 5751 in this amp without damage?

John