No deep bass or highs: VTF or VTA issue?

Here is a link to a white paper that another A'goner referenced several days ago. I think the concepts presented in this paper will help explain why your theory of what large changes show is full of holes. So don't despair yet.

Vacuum State GuruSetup

What you describe as shimmering from your digital source is, as Piedpiper points out, not correct. I've used that term incorrectly myself so I'm not sure I understand exactly what you are talking about. Shimmering implies something is being added and is most likely an artifact. What you want is that strike and long decay from cymbals. I'd be curious to compare your music server to a decent redback cdp.

At the same time I think I understand what you're saying about the cymbals on Deacon Blue's. I'll pull out my copy today and get more familiar with your reference.

Hi Floyd,

Based on what I’ve read from you so far, I’d suggest the following in its entirety as a test:

- Set the tracking force to 1.8 grams (If the cart/arm combo tracks at 1.7, you can try that short term for this test)

- Raise VTA until bass just begins to fall off.

- Set the cartridge loading on the Rhea to its highest setting (47K Ohms?). Also, make sure you are setting that loading for the input you are using on the Rhea since it has three of them.

- Remove all clamps and record mats

Once you have done the following setup above, check to see if you are getting any additional “air” from the cartridge. If you are getting progress and can still track records well, you may be going in the right direction. This test can result in a very bright sound in many setups but we are looking for the “air” and then want to bring things back to normal from that point. Please let me know the results of this test.

If the test above doesn’t show any signs of improvement, the information gained may be pointing to one of the following remaining possibilities outside of cartridge setup/maintenance :

- Your VTF gauge may not be working correctly. BTW, which one are you using?

-The use of NOS tubes in the Rhea is limiting the high frequency reproduction of the phonostage (as well as the low frequencies you noted by using the Steelhead).

-The 9 inch VPI uni-pivot arm may not be able to exert enough control over the XV-1s to reveal the low-level detail and the higher frequencies you are looking for.

-A possible issue with the interconnect between cartridge and phonostage or the Phonostage and the Preamp.

Some general thoughts are that the sound of the digital rig is more inline with your tastes in music playback. As such, you may want to borrow a solid state phonostage that is fairly detailed as a next experiment to see if it produces a more extended top-end that is more in line with your preference. There are probably some tubes you can roll in the Rhea to achieve the same things. The point is to take advantage to being able to borrow a few components before you invest heavily in an unknown solution.

Hope this helps,
Dre

Dan: thanks for the white paper, I'll digest it. When I mentioned 'shimmering', I meant the decay of the cymbals (as they vibrate). I think I know what you mean by digital shimmer; I used the term incorrectly.

Dre: I really appreciate your post. I'm just now switching back to the Manley again and have been wondering about the interconnects. I'm using a Pro-ject gauge (it appears the same as most other digital gauges I've seen - perhaps all made in the same Chinese factory?).

I'll try your suggestions. Btw, what happens when a cartridge 'mistracks'? I assume it would be obvious when it happens, but haven't experienced that yet so I'm curious.

Thanks.
Ian

Ian,

Excellent advice from Dre. Just trying 1.80g isn't enough, since no two cartridges are exactly alike. You need to keep going lower until you loose bass/dynamics and/or reach the mistracking point, then start moving VTF back up in very small (.01-.02g) increments.

Mistracking sounds like:
- if slight - a trace of fuzziness on strong, high frequency notes
- if severe - short bursts of static-like noise, like high frequency “farts” (sorry!), provided that they’re in synch with dynamic peaks or strongly held notes and not in synch with LP revolutions (which would tend to indicate pressing flaws in the vinyl)

Ian,

I’m sorry I called you Floyd based on your forum tag.

Your gauge is one of the typical ones used and it should work well. To test the gauge (crudely) you can place a dime on the gauge. The dimes after 1965 should be in the ballpark of 2.268 grams. I checked 7 dimes plus had a friend check another 10 to 12 and we both came up with around 2.26-2.28 average with a very small number reading 2.29 and 2.24. So, somewhere in that range will give you a general idea if the scale is working properly. I suspect it's OK.

Mistracking can take on many forms depending on the type of music being played. So I don't take this thread off topic, I'll just state that mistracking is an artifact of the stylus not staying in contact with the groove wall. This results in audible breakup of the sound being reproduced. Sometimes it may favor one channel over the other. In other instances, it will mistrack in both channels during the same high velocity amplitude level (a function of anti-skate). In any event, gross mistracking will be clearly audible. If you want to hear what some types of mistracking sound like, take an old LP that you don't care about and lighten the tracking force on your arm until you begin to experience a distortion (fuzzy, humming, crackling sound) like presence added to your music that you know is not supposed to be there. This is not all encompassing of the types of audible mistracking by any means. There are probably a few threads on the forum that discuss this phenomena in more detail. Again, so I don't cloud your thread with a new issue, I'd suggest reviewing one of the threads already here on the forum.

A side bit of information for you: I played all three copies of Aja that I have and I hear the missing information (Cymbal decay) clearly. In fact, the decay is extended so much that it never completely goes away before the next cymbal strike during the opening of Deacon Blues.

Hope this helps,
Dre