Ar Xb - Terrible Crackling Noise, And Distotion.

[Hawkeye666]

I recently took possession of an AR XB. It came in all the original packing and the only non-stock item was the Shure M91 had been replaced with a Pickering XV-15/400E. I get the Vinyl Nirvana cleaning kit with new belt and gave ti a very thorough cleaning. It was in very good shape anyway.

I went to play some vinyl on it and noticed that it was pretty scratchy sounding. The same LP played on my existing Denon DP-7f was nowhere near as scratchy nor did it have the same distortion in high gain areas, or sections of songs with lots of instruments all at higher volumes.

So I thought new stylus. I upgrade from the D400 to the D625. And though it might be a tiny bit better is is still bad enough that I much prefer listening to the Denon.

I have spent no small amount of time checking over hang and making sure the cart is aligned in the head correctly. I've played with tracking forces from 1.5 to 2.25. It got better at about 2, which is the high end of the recommended tracking force, and seems no better if I increase past that.

I've tried four different mats, and even no mat at all. I hear no real difference between then at all. Ground is good, I've go no hum. I've tried it through the receiver, which has a good phono stage as well as through the Cambridge 640P I bought for it. No differences. Speed looks right on and sounds as "in tune" as the other table. And I have near perfect pitch so my by ear is pretty good.

I'm going to try and put a different cart on it now and see if that makes any real difference, but I'm not holding out much hope right now. After that I'm at a loss as to what to try next so I need some ideas.

[Alec124c41]

Change the cartridge.

Cheers,
Alec

[ddarch]

Agreed. Report back.

Dave

[Hawkeye666]

I have learned two things so far...

1. Never assume the person from whom you bought the turntable bothered to make sure the leads to the cart were connected to the correct pins. After refering to both the TT manual and the one for the cart the crackling has disappeared. As Todd Rundgren would sing, "Give me just one victory..."

2. I now have the beginnings of an understanding of the concept of tonearm mass, and the effect it has when combined with different weights of cartridges.

How does the default Pickering XV-15 stylus come? With that cute little brush connect to it. That cute little brush weighs about as much as the rest of the cartridge with stylus on it. So I'm thinking, maybe that's too freaking heavy. So I take it off, rebalance the tonearm to 1.65 and distortion is much diminished. However I still think the Denon sounds better. At certain frequency combinations the AR sort of fuzzes out. I haven't tried my Orion test record on it yet. Probably do that tomorrow. The Denon has a 17 year old AT400 p-mount with a new $125 Shibata stylus, whereas the Pickering is 36 years old and has a $40 stylus.

Should I try the AT on the AR next? I have the p-mount to universal adapter?

Which alignment template should I use for the AR?

The over hang is good and I've got everything pretty well leveled. Should I try more tracking force?

[snfrosten]

Try the 625 in the Denon to make sure it is not the cart.

Also make sure the pivot screws in the arm boss are set so there is no play. Most tables I service have this problem.

[Hawkeye666]

Try the 625 in the Denon to make sure it is not the cart.

Also make sure the pivot screws in the arm boss are set so there is no play. Most tables I service have this problem.

Denon is p-mount so cannot try the Pickering in it.

I'll check the screws after Vivaldi finishes.

[Hawkeye666]

And before I forget thanks to all of you for your ideas and input.

Keep them coming.

[wordwizard]

Change the cartridge....

I thought you were going to suggest DeOxit.... <g,d,ra>

[Hawkeye666]

I checked the set screws on the pivot block on the tonearm and they are tight. But as I was doing so I noticed something that seems a tad strange to me. There is a definite low level electrical current flowing through that block. When I touch it I can feel the current tingling my finger.

Should it do that?

Might I have a ground not connect underneath or something?

[Alec124c41]

Try reversing the power plug in the socket.

Cheers,
Alec

[pogo]

Try reversing the power plug in the socket.

Cheers,
Alec

Alec, I get what you're saying but no way or form should power AC appear on the tonearm. I'd suggest also, unplugging and getting under the table specifically looking for anywhere that an unprotected connection or damaged wire in the power circuit might contact the metal top.

Might revise that to include first disconnecting from the amp. But you really need a way to test what's present (voltmeter) I'm not keen on checking by touching if it's already buzzed you.

I'm going to assume when you say "tingle" that you're not talking static -- in other words it persists as long as you're in contact. I'm sometimes zapped by contact with my arms, but I'm (un)fortunate enough to live somewhere that sports relative humidity as low as 4%. Makes a hell of a crackle when it happens, though.

[Hawkeye666]

[quote="Alec124c41"I'm (un)fortunate enough to live somewhere that sports relative humidity as low as 4%. Makes a hell of a crackle when it happens, though.

"Yeah, but its a DRY heat!"

[pivot]

I agree there should be no AC line current on the tonearm.

Unplug and get inside. The motor circuit should be isolated from the top plate and sub-chassis. Somehow something in the motor circuit maybe shorting against a metal part that is should not.

Fix that before any other fussing about.

[Hawkeye666]

I took the Audio Technica AT450 off the Denon and put it on the AR.

No question about it the AT450 with the Shibata is far better than the Pickering with the new D625 stylus. It is more accurate in all frequency ranges. By the way the AT450 I have uses the ATS8008 stylus and is not either of the AT450s (E/OOC) in the database. The model number I'm quoting is from the body of the cart and not the stylus.

If I have any negative critique it is that it is a little too out front in about the 10k to 16k and higher range. But a tiny lowering of these two sliders on the EQ took that slightly splashiness out quite nicely.

So I either leave the AT on the AR, or I get a new cart for it. I would sort of like to be able to use both tables since I have a pretty good phono stage in my receiver as well as the Cambridge. Soooo...

Given an AR XB, running into a Cambridge 640p phone stage, and JBL LX-500 speakers, what cart should I look at? Let's set the cost parameter between say $150 to $200 USD. And would it be worth it to spend some more for instance to go MC instead of MM?

Once again your experience is greatly appreciated as I learn all this stuff.