VTA for arm vs VTA for cartridge


Hi have a Thorens 125 MKII, SME 3009 Series II tone arm and Grado Gold cartridge.

I've been looking for a better bass response, and decided to reassess my VTA.

It was set for the tone arm (arm horizontal to the record, or nearly so). I tried lowering it, but didn't get the improvement in bass I was hoping for.

Something motivated me to check my cartridge instructions. The VTA for the cart is supposed to be set so that the base is horizontal. Because of the way its designed the arm ends up angling down. This makes sense as far as the cart is concerned, even if it defies the tone arm instructions.

I have a thick mat which makes it impossible to get this exactly right. But it is just a bit lower now than the correct VTA now.

Here's the interesting thing. When I compare the bass and highs, etc. in recordings from both VTA setups I don't hear much difference. In fact, the bass seems a little more prominent in the VTA I set had originally set for the arm.

Maybe it all too subtle to tell with my headphones right now.
gritingrooves
Follow Lloyd Walker's fine tuning instructions to which you provided the link, Gritingrooves. After getting the arm and cartridge in place as best you can visually, let your ears be your guide in the iterative listening process Lloyd describes and you will get good results. This is the best process for fine tuning a turntable setup I've ever used.
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I contacted Grado, and got the feedback that "cartridge must be parallel to the record". Guess the tone arm requirements are secondary.

So, at least according to the cart maker, that is my starting point.
Yes, agree the cartridge should be your starting point. The angle of the arm is irrelevant in and of itself. This is all about getting the angle of the stylus in the groove set correctly. Here's a good diagram illustrating what you're looking to accomplish.
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On almost all of the arms I am familiar with, the arm tube is parallel to the headshell, even if both are not in the same plane. Assuming that the cartridge bottom is parallel to its top, then, all three -- arm tube, headshell and cartrige would be fixed at the same angle. Therefore, if the manufacturer says to keep the cartridge parallel to the record, the easiest way to determine this is to look at the arm tube because of its much greater length. I like using a ruled 3 x 5 index card placed behind the tonearm when the arm is on the record surface in the playing position. This establishes a parallel starting point from which one can make adjustments.

If the sound is brittle, sibilant and harsh sounding, one needs to lower the arm. If it sounds too shutdown on top, muddled and dull (like a blanket has been thrown over the speaker) then raise the arm at the base. Lowering the arm may restore bass that is lost due to incorrect VTA, but, it cannot really ADD bass that is not there in the system. I personally would not use VTA adjustment as a means to increase bass -- correct VTA improves imaging, top end response, recovery of room ambience cues, etc., more than anything else.
I just read that you do your evaluations with headphones. I have the Sennheiser 650's with Cardas balanced upgraded cables and use the Headroom Blockhead (top of the line) headphone amp. The sound is in many ways better than my speakers, but for some reason is much less sensitive to the fine adjustments on the cartridge/arm/table interface. I don't know why, but to really evaluate the differences, I have to use the speakers.