Too much gain?

roscoeiii · « **Reply #40 on:** 11 Dec 2012, 07:04 pm »

I am confused. If the issue is still there with your previous phono stage, as well as the Chinook, and not with the CD player, why do you rule out the TT?

vortrex · « **Reply #41 on:** 11 Dec 2012, 07:34 pm »

Quote from: roscoeiii on 11 Dec 2012, 07:04 pm

I am confused. If the issue is still there with your previous phono stage, as well as the Chinook, and not with the CD player, why do you rule out the TT?

because it happens when there is no TT connected. Manley had me short the inputs to the Chinook and the issue is still there.

orientalexpress · « **Reply #42 on:** 11 Dec 2012, 07:43 pm »

one way to rule out the turntable is use another turntable or borrow one.

vortrex · « **Reply #43 on:** 11 Dec 2012, 07:49 pm »

I think having the TT disconnected and sitting in the other room proves it's not the table.

roscoeiii · « **Reply #44 on:** 11 Dec 2012, 07:58 pm »

Hmm, that is pretty good evidence. The quiet of the CD player still remains part of the mystery for me, with both phono preamps giving you the problem. Get the amp from a dealer? Talked about this with that amp dealer yet?

orientalexpress · « **Reply #45 on:** 11 Dec 2012, 08:16 pm »

Well ,it's not turntable

,have you try your phonostage on a different input on the pre amp or try a different pre amp.

vortrex · « **Reply #46 on:** 11 Dec 2012, 08:23 pm »

Quote from: roscoeiii on 11 Dec 2012, 07:58 pm

Hmm, that is pretty good evidence. The quiet of the CD player still remains part of the mystery for me, with both phono preamps giving you the problem. Get the amp from a dealer? Talked about this with that amp dealer yet?

Yes and yes. He's baffled too. I really don't think it is the amp. If it comes to it I could haul it to his place, but I would rather not. This thing is like 70 lbs.

vortrex · « **Reply #47 on:** 11 Dec 2012, 08:23 pm »

Quote from: orientalexpress on 11 Dec 2012, 08:16 pm

Well ,it's not turntable ,have you try your phonostage on a different input on the pre amp or try a different pre amp.

It's an integrated. Yes, I have tried all the inputs, same thing.

neobop · « **Reply #48 on:** 11 Dec 2012, 08:44 pm »

Quote from: vortrex on 11 Dec 2012, 06:22 am

The same hum is there without the SUT being used, so I don't think it has anything to do with it.

Did you disconnect the ground wire from the SUT, if not you could still have a ground loop.

"If I remove the SUT from the path and use the MM inputs of the phono pre it's better. The volume knob is now around 10 o'clock at my max level (which is probably middle of the ground), but there still is a low level hum. It sounds better with the SUT though so I really want to use it."

What does that mean, it's better but still a low level hum?

"ahhh, ignore anything related to the TT. I forgot I had troubleshot with Manley and we shorted the inputs to the Chinook and the issue is still there. now you might say it is the Chinook, but if I put my K&K back in (using the RCA outs) it has the same issue."

Both the Chinook and K&K would have a similar issue if there is a ground fault or loop. Did you test them with everything disconnected?
You're much more likely to pick up AC hum on a phono input, could that be it?

Seems like neither phono stage likes the new integrated. Also seems unlikely that both phono stages have an issue.
neo

vortrex · « **Reply #49 on:** 11 Dec 2012, 09:04 pm »

Quote from: neobop on 11 Dec 2012, 08:44 pm

Did you disconnect the ground wire from the SUT, if not you could still have a ground loop.

"If I remove the SUT from the path and use the MM inputs of the phono pre it's better. The volume knob is now around 10 o'clock at my max level (which is probably middle of the ground), but there still is a low level hum. It sounds better with the SUT though so I really want to use it."

What does that mean, it's better but still a low level hum?

"ahhh, ignore anything related to the TT. I forgot I had troubleshot with Manley and we shorted the inputs to the Chinook and the issue is still there. now you might say it is the Chinook, but if I put my K&K back in (using the RCA outs) it has the same issue."

Both the Chinook and K&K would have a similar issue if there is a ground fault or loop. Did you test them with everything disconnected?
You're much more likely to pick up AC hum on a phono input, could that be it?

Seems like neither phono stage likes the new integrated. Also seems unlikely that both phono stages have an issue.
neo

sorry for not being more clear. in that case, when I said "better" I only meant the sensitivity of the volume control. the hum/noise is the same. and yes, when I removed the SUT I did have the ground removed also.

vortrex · « **Reply #50 on:** 11 Dec 2012, 10:32 pm »

this is 4 miles away, would it matter?

watercourse · « **Reply #51 on:** 13 Dec 2012, 12:52 am »

Here in San Fran, everyone in the city is within 4 miles of a tower that big, so I don't think it's likely as I've never had hum problems...

vortrex · « **Reply #52 on:** 13 Dec 2012, 04:15 am »

Quote from: watercourse on 13 Dec 2012, 12:52 am

Here in San Fran, everyone in the city is within 4 miles of a tower that big, so I don't think it's likely as I've never had hum problems...

I guess we're both near that same tower then...

watercourse · « **Reply #53 on:** 13 Dec 2012, 04:34 am »

looks like twin peaks to me, on a very nice day

neobop · « **Reply #54 on:** 13 Dec 2012, 07:52 pm »

Quote from: watercourse on 13 Dec 2012, 12:52 am

Here in San Fran, everyone in the city is within 4 miles of a tower that big, so I don't think it's likely as I've never had hum problems...

It's not likely but it is possible, depending on the bandwidth of the component, shielding etc. Once I was at a friend's place in Jersey and we picked up a radio station in Japan, on his phono stage.

But it would be even more unlikely for both pieces to fall victim. I think balanced line rejects up to 6dB of common hum/noise. You run unbalanced from the tonearm to phono pre and previously ran balanced from phono to line stage? You're not running balanced to unbalanced adaptors on the arm cable? That would be too easy. It does seem like a grounding problem though.
neo

watercourse · « **Reply #55 on:** 13 Dec 2012, 08:02 pm »

100% in agreement neobop. The short ICs that you are using would also argue against RFI, but it is not impossible.

Ericus Rex · « **Reply #56 on:** 13 Dec 2012, 08:18 pm »

Doesn't the fact that the hum goes up and down with the volume control imply the cartridge is the culprit? I've never experienced a ground loop hum being volume adjustable.

To be sure it's not the phono stage unplug the tonearm cable and turn everything on. If the hum is gone then your culprit is ahead of the phono section; either the cartridge (are the leads secure?) or the SUT, or their cabling. If the hum is still there then your phono pre, or its cabling, or its interaction with nearby power supplies is likely the demon.

watercourse · « **Reply #57 on:** 13 Dec 2012, 08:26 pm »

I thought vortrex already isolated the TT from the variables, leaving the phono stage and possible grounding issues, or hum pickup from AC, RFI, transformers, or other sources?

roscoeiii · « **Reply #58 on:** 13 Dec 2012, 08:32 pm »

Quote from: Ericus Rex on 13 Dec 2012, 08:18 pm

the fact that the hum goes up and down with the volume control

Yes, this is the puzzling bit for me, along with no hum from CD player, but hum from both phono stages even with no TT attached. Quite the mystery.

Does your dealer do house calls?

vortrex · « **Reply #59 on:** 13 Dec 2012, 09:28 pm »

Quote from: neobop on 13 Dec 2012, 07:52 pm

You run unbalanced from the tonearm to phono pre and previously ran balanced from phono to line stage? You're not running balanced to unbalanced adaptors on the arm cable? That would be too easy. It does seem like a grounding problem though.
neo

previous was unbalanced from arm to phono pre and balanced from phono pre to amp.

current is unbalanced all the way through. IC's are short (.7m is the longest).