[wakibaki]

I'm relaying the info here that was given to me when I spoke on the phone to the designer of my phono pre.  he's the guy who designed and built a phono stage that has received nothing but praise from every professional reviewer and end user.  unfortunately because I am not as technical as you I cannot relay everything he said, but he did say it was because of the high input sensitivity of my amp.

Why do you think he said that?

He said it because you are a customer, you are complaining, he's run out of things to say and he has to say something to get rid of you. You do understand that not everybody tells the truth all the time? Especially when they're trying to get rid of an awkward customer.

w

[vortrex]

I'm not his customer.  I bought the unit used.  I haven't complained one bit to him.  I did not ask to speak with him on the phone, he offered up his time to me.  George is a really nice guy.

Sounds like you have some emotional issues to work out.  My advice would be to focus on that instead of trying to convince people that you're an expert amp designer.

I just looked through your entire post history and literally every comment you have made since 2011 is bitter, angry, confrontational, and with a know it all attitude.  good job buddy!

[Pete Schumacher]

Hey Vortrex,

If your input stage gain is much higher than it needs to be to amplify the phono input, there's every chance that the noise that you hear regardless whether the input is shorted or driven with a phono stage is coming directly from the preamp stage in the integrated amp.  If you reduce the gain of that stage, its self-induced noise at the input will drop along with the gain reduction.  The best course of action is to find the part of the circuit that amplifies the input, maybe an op-amp or transistor/tube amp, and adjust the gain to the level you think it needs to be.  In most cases, one resistor for each channel would be all you'd need.

I know a tech who can handle that for you if you don't have one local.

[vortrex]

I asked the manufacturer of the amp about the gain and their response was...

"Regarding gain of LM-218IA the total gain of it is 35dB. No separate gain for the pre-amp and amp section."

[Folsom]

Hey Vortrex,

If your input stage gain is much higher than it needs to be to amplify the phono input, there's every chance that the noise that you hear regardless whether the input is shorted or driven with a phono stage is coming directly from the preamp stage in the integrated amp.  If you reduce the gain of that stage, its self-induced noise at the input will drop along with the gain reduction.  The best course of action is to find the part of the circuit that amplifies the input, maybe an op-amp or transistor/tube amp, and adjust the gain to the level you think it needs to be.  In most cases, one resistor for each channel would be all you'd need.

I know a tech who can handle that for you if you don't have one local.

I thought about this too, but found it a bit difficult to believe. Unless something is over driven it seems unlikely. Could it be possible a SUT has a different affect on frequencies not in the audio-band? That could overdrive the preamp section on an amplifier, potentially, at nearly any volume.

What about noise that is identical and getting amplified in both phono preamplifier and amplifier? Reducing the gain the phono would lower this, and hence it wouldn't be as loud in the amplifier.

vortex what is your stuff plugged into; and are there any notable electrical devices near you? (laundry mat or something)

Pete's suggestion might work depending on how the tubes are wired up. Still though if the noise is very high frequency or very low, it could cause the audible problem even with gain changed.

[vortrex]

I don't think it is my environment.  I've shut off all breakers in the house, unplugged everything from every outlet except the amp and phono pre, disconnected the cable TV line as it enters the house from the street...no change at all.  my previous system was dead quiet in the exact same arrangement.  I have my rig running through an UberBUSS now.

keep in mind I had the exact same problem with the Chinook at 60db, with no SUT involved at all.

[Pete Schumacher]

I went back and read the first post again to refresh.

If you're plugging in the CD and its dead quiet, but noisy with the phono pre, then the phono pre is the source of the noise, and reducing the gain of the phono pre will reduce the noise that it's putting out.

I was under the mistaken impression that you shorted the amp inputs when you actually shorted the phono pre inputs.
Phono stages are just plain noisy when compared with most digital sources

If you have plenty of volume knob left before the amp is at max with the phono input going, you should be able to cut the gain of the phono quite a bit and reduce the noise.

[vortrex]

I understand digital will likely be more quiet, but I've had plenty of analog rigs more quiet than what I have now.  my first $400 phono pre was more quiet than this.  I have a hard time believing the Zesto is this noisy by nature, because I think it would be very hard to sell them.  I've stuck with it because despite the background noise it is one incredible sounding phono stage.  also, with 35db of gain for my integrated that does not seem that out of the ordinary, right?  guess I am still trying to understand what specific thing is it with my system that others are not experiencing in theirs.  I do have plenty of knob left, too much, 9 o'clock is my max listening level.
 

[Folsom]

I understand digital will likely be more quiet, but I've had plenty of analog rigs more quiet than what I have now.  my first $400 phono pre was more quiet than this.  I have a hard time believing the Zesto is this noisy by nature, because I think it would be very hard to sell them.  I've stuck with it because despite the background noise it is one incredible sounding phono stage.  also, with 35db of gain for my integrated that does not seem that out of the ordinary, right?  guess I am still trying to understand what specific thing is it with my system that others are not experiencing in theirs.  I do have plenty of knob left, too much, 9 o'clock is my max listening level.

What is the max listening level position with a CD player?

[vortrex]

I'll have to hook it up tomorrow and check.  It's not something I ever use for for music.

[Pete Schumacher]

35dB is pretty high, but it's not unusual I suppose.  Most amps have a gain set to somewhere near 25dB, more or less.  Having an extra 10dB available from the pre-stage would seem about right.

But it all comes back to CD source vs. phono source and the noise that's picked up at the integrated amp input.  If the phono is noisy, but not the CD, then we've pretty much identified that the phono stage in question is the cause, reputation aside.

I assume you're using the same RCA cables to connect either the CD or the phono.

[wakibaki]

If you're plugging in the CD and its dead quiet, but noisy with the phono pre, then the phono pre is the source of the noise.

What did I say?

There was nothing angry or confrontational about my first post. Far from it. I took a lot of time to explain the situation to you in simple terms. I'd also like to point out that up to that time you had not a single reply.

Yes, I became increasingly impatient at your continuing attitude. I'm only human.

I don't pretend to be an amplifier designer. Go take a look at my website wakibaki.com or look at the numerous designs I have posted on Head-Fi and which people all round the world are building. When you can design your way out of a paper bag you'll begin to be in a position to criticize.

The one other useful suggestion that has been made is that you could try a buffer. CDPs in general have a low output impedance. Your phono has a comparatively high output impedance. Given that the integrated amp has 100k input impedance, this should make very little difference, but it is just possible that you might see some improvement when the integrated input is shunted by the low output impedance of a buffer.

w

[vortrex]

dude, move along.  you are clearly nuts and the writings on your site and ALL your previous posts here reflect that.  if you would take the time to actually read the info I have provided here you would see I have the same issue whether I am using a pre with 200ohm output or one with 10kohm output.  I am clearly not a designer or I wouldn't be looking for help here.

[Gzerro]

I recently auditioned both the Chinook and Zesto and they were dead quiet with the dealers setup. He really cranked the volume (without a record on) and the background noise was barely audible.

Have you tried swapping out a different pre-amp/integrated? Perhaps you have a friend that would let you borrow one? That would at least narrow down the possibilities.

[vortrex]

I recently auditioned both the Chinook and Zesto and they were dead quiet with the dealers setup. He really cranked the volume (without a record on) and the background noise was barely audible.

Have you tried swapping out a different pre-amp/integrated? Perhaps you have a friend that would let you borrow one? That would at least narrow down the possibilities.

that's what I have heard, thanks for confirming that.  like I said, there is no way these units would sell with this amount of noise, let alone be two of the best phono pre's available today at their price points.  if you crank up the volume on mine in that same way you can literally see the woofers moving from all the noise.  at my listening levels the noise is only apparent during quiet passages, but I also have a feeling if it were completely eliminated I would notice that veil removed.  I don't know anyone around here with an amp to borrow.  I could dig out my cheap SS receiver that I use for my TV.  think this would bring me back to the mismatching issue again.

[vortrex]

here are some crude measurements I did before with an app on my phone.  now this is with the volume knob pegged, but you can get a feeling for the huge difference in noise level.

CDP connected or no input connected to the amp = 28-30db
phono stage connected (with table or not) = 68-70db and can spike up to 75db

[Quiet Earth]

Vortrex,
I think you're chasing your tail man. But let's remain calm and just share experiences to confirm.

My tube amplifier has almost the same sensitivity as your LineMagnetic. Mine is 250mV for full power, and yours is 210mV. My amp also has 100k input impedance. One thing I don't remember is your speaker sensitivity, but we'll skip that for now. I have a tube phono preamp that is switchable between 40 and 60 dB of gain (MM or MC) and a high output moving coil which canwork with either setting. When I use the 60db setting I can also hear noise in the quiet passages of music. I can hear the noise with no music playing and the input shorted too. I don't like that. When I switch to 40dB the noise is gone. Dead quiet. So what's the deal?

TOO MUCH GAIN.

You can't line up that much gain and not have noise. That's just the way it is. If your speakers are really inefficient then maybe you can get by, but gain is gain, and when you have that much gain you have noise.

You got better results with the Leben so I suggest you head back down toward that path if you want less noise. If you absolutely have to have a LOMC cartridge then you need a phono pre with 35-40 dB gain and a step up transformer. A good tranny is not cheap and there are placement issues to consider, as you well know.

Btw,  this is exactly the reason why I am getting rid of my HOMC and upgrading to a better moving magnet cartridge and not going for LOMC. It's too expensive to do it right and I can't stand the damn noise either. There are some really nice MM carts out there, and I believe that you and I are the kind of people who can appreciate them.

Don't keep doing the same thing and expect less noise. Change cartridges.
Good luck brother-man!

[vortrex]

You got better results with the Leben so I suggest you head back down toward that path if you want less noise. If you absolutely have to have a LOMC cartridge then you need a phono pre with 35-40 dB gain and a step up transformer. A good tranny is not cheap and there are placement issues to consider, as you well know.

but this is exactly what I had and it was very bad.  the SUT's are typically 26db, which puts me right back to what I have now at ~65db.

so it sounds like I am better off with a higher output MC (my current is .25mv) and then a phono pre with less gain?  I thought if I dropped the gain significantly with a LOMC it's going to affect the performance of the cart?

[wakibaki]

dude, move along.  you are clearly nuts and the writings on your site and ALL your previous posts here reflect that.

Perhaps now, if you are done venting, you will be able to hear what I and others have been trying to tell you.

[Ericus Rex]

This is the second thread regarding this problem.  Over the several pages of both threads you've gotten some really good advice that has not worked for you.  Maybe it's time to sell everything and start over from scratch?  Or at least replace the integrated?