if you want to hear the best possible performance overhang is very important. perfectly mounted modestly priced cartridges will outperform poorly mounted expensive cartridges. the vinyl groove is picky about how the stylus 'sees' the groove surfaces. until you get it right you will not know what you are missing.
i looked at the manual for your turntable. it does not describe whether your tonearm mounting position is adjustable. i will try to explain.
as your turntable appears to be sold as a tt/arm 'package' i assume the pivot to spindle distance is fixed. when the tonearm mounting position is adjustable then when a cartridge has a non-standard relationship between the mounting screw holes and stylus position the arm can be moved to allow a proper overhang.
the only thing that matters is hitting the arc precisely. if you cannot hit the arc on the Mint exactly with the arm and headshell in their current postion then either;
1. you need to move the arm mounting position.
2. you need to somehow adjust the headshell postion.
3. get a different cartridge that fits.
4. settle for an improper alignment.
my recommendation would be to speak to the dealer that sold you that tt, or someone else who owns one, and run thru what you have done.
hopefully when you look closer there will be some sort of arm mounting adjustment. |
There are many ways to adjust overhang and some are quite different: Baerwald, Loefgren or Stevenson. Vinylengine.com has a great section on cartridge alignment and you can download and print different protractors. Maybe you can find the right one that will work with your cartridge and turntable. |
Hi, Wilson667; the first question (just to be sure) is what are the spindle-to-pivot and effective length distances that your Mint protractor is designed to accomodate? The second question is what is the distance (measured as best you can) from the mounting holes in the cartridge to the stylus tip?
If the Mint protractor is designed for a spindle-to-pivot distance of 212mm and an effective length of 230mm then it's a match for the 9cc arm that comes with the Experience 2. (Sorry if you know that already; just helps to troubleshoot if all the information is available.)
As for the Ortofon HMC20, if the distance from the mounting holes to the stylus is about 6mm or more you should be able to set overhang correctly. That's assuming the 9cc has slots in the headshell the same as the headshell on a 9 aluminum arm. If the mounting hole to stylus distance is less than 6mm it may require you to use a different protractor and a different alignment geometry. Between the handy alignment geometry calculators available at VinylEngine and the TemplateGen (custom) protractor available from Conrad Hoffman you'll find something that could work very well.
Tom |
Maybe I'm missing something. It is hard to get the picture without seeing it.
I'll assume you have followed others advice and have verified the P2S.
You say that the cart is all the way forward, it hits the arc on the outside but sits behind the arc on the inside. And that the cartridge is all the way forward in the slots.
So, if you move the Mint protractor back until the stylus is on the arc at the inside, will the cart not be too far forward on the outside now? Which is ok, because you can move the cart back in its slots.
Of course after you move the cart back, you will now need to move the protractor again to align the inside and then recheck the outside again. Keep doing this, correctly, and you should find that everything is converging on the arc. Using an arc protractor is an iterative process. I think you just need some practice.
Perhaps it will be easier to start with the cart in the middle of the slots? |
The only point to overhang and pivot to spindle distance and offset and such is to help you get a starting point to better align the stylus to the appropriate null points on the curve (Lofgren or Baerwald and such). That's the purpose of these things. If you don't take the pain to set them exactly, but still manage to somehow align the stylus appropriately, I will bet that you have inadvertantly gotten them very close to where they should be.
But why take that chance and make it more difficult for yourself? Set it right the first time, then listen to music. |
Dan_ed wrote:You say that the cart is all the way forward, it hits the arc on the outside but sits behind the arc on the inside. And that the cartridge is all the way forward in the slots. From the setup instructions I've been able to see online for arc protractors, the condition the OP described does indeed indicate that there is not enough overhang adjustment possible. http://db.audioasylum.com/cgi/m.mpl?forum=vinyl&n=738382It's always possible that his Mint protractor was mis-manufactured or that his turntable doesn't exactly match published specifications for arm length, pivot to spindle distance, etc. I agree with others that trying a different protractor is the best first step. If he doesn't have enough overhang for Baerwald alignment, maybe a Stevenson protractor will work. Two-point protractors and single-point, line of sight protractors (such as the Geo-Disc) can work with a variety of turntables and arms as they are not "tailor-made for a particular turntable tonearm setup"; even the best tailors can make a mistake. |
That write up from John assumes the arc is in the correct position. You can't just flop down an arc on the table any where.
Again, very important, I'm assuming the arm is set to the correct P2S.
Look at John's drawing, keep in mind the cartridge is all the way forward. From the OP's description it seems that the cartridge is hitting point C. However, the cart is already too far forward.
Now move the arc back until the stylus at point C is on the line. Where did the stylus move to in relation to the arc on the outside? Does it not end up to the left of the arc? |
Many of us who use the MintLp protractor on a regular basis have found an easy check of the arc position on the table. First, start with the cartridge in the middle of the slots. Then, with the arm lifted on the queue, gently swing the arm across above the arc. You should be able to see if you are in the ballpark or not. If not, move the protractor until it looks like the arm is tracing the arc. Now you should be reasonably close and you can begin adjusting the cart with the stylus down on the protractor. |
sorry I haven't been on in a bit . Dan_ed you are exactly right if the Mint had a C point that is where the stylus is landing and if you move the protractor so it lands on the arc near C then at A it is to the left of the arc.I have been talking with Yip at Mint and we have come to the conclusion that the Ortofon HMC 20 cartridge only has a Mounting Hole to Stylus Tip of 8.5mm instead of the standard 9.5mm. That looks to be the amount of adjustment missing. Since it looks like I may have to replace the cartridge does anyone have any suggestions on a sub $500.00 cart. with a known longer MHST measurement.Ortofon would be preferred just because of the trade in, but it is not a must |
Hi, Wilson667: A difference of only 1.0mm should not prohibit you from adjusting the position of the cartridge in the 9cc tone arm headshell to align to the Lofgren A/Baerwald geometry. The headshell slots have enough play forward and backward from the middle position, which accomodates most cartridges with typical mounting hole to stylus distances of +/- 9.5mm, to easily accomodate your HMC 20.
Something doesn't sound right. Before spending money on another cartridge, try using the Conrad Hoffman protractor, which works very well for the Pro-Ject tone arms. Download from the link, unzip, print, and follow directions in the README file.
http://www.conradhoffman.com/TemplateGen.zip
Tom |
Wilson667,
When you moved the protractor back to get the stylus to land to the left, could you then move the cart back in the slots toward the line? If not, I suspect that the arm is not mounted exactly at the P2S distance. However, the distance between the stylus and the line will give you an idea of how much the arm pivot is off. I remember the Pro-ject arm I had on an MMF-7 a while back, but don't remember how much play there is in the three set screws that hold VTA. Maybe it is possible to play with this and get the P2S correct? Can you measure carefully what the P2S distance is now?
Granted, a short hole-to-tip makes life a bit difficult but if things are set correctly and your arm has slots for mounting the cartridge it should work. There is no standard for the hole-to-tip distance. That is why most arms have those headshell slots. |
Dan_ed; I would also consider that the Mink protractor may not be constructed correctly. If the wrong parameters were given or used to set the markings on the protractor that could also account for the problem trying to use it with the Pro-Ject 9cc tone arm. There should be more than enough play in the headshell slots to accomodate a 1.0mm difference in cartridge mounting hole to stylus tip distance. Unless Pro-Ject has recently redesigned the 9 series tone arms, a typical cartridge with 9.5mm mounting holes to stylus tip distance puts the cartridge right in the middle of the slots with almost 3mm of travel fore and aft.
That's why I asked what dimensions were used to create the Mink protractor: Are they the correct dimensions? Using parameters of 212mm spindle-to-pivot distance and a 230mm effective length the cartridge should easily align to a Lofgren A/Baerwald geometry with the Pro-Ject 'arm. And also why I suggested using another protractor with the correct parameters to compare with the Mink protractor. Conrad Hoffman's TemplateGen is a quick way to check. That would indicate if it's the Pro-Ject turntable or the Mink protractor that was possibly mismanufactured.
Until more information is provided all bets are off as to what is causing the problem.
Tom |
Hi Wilson,
I used to have a Pro-Ject as well. When I owned it I bought and kept the Sumiko Pro-Ject protractor and alignment kit. This is specially designed to work with Pro-Jects and is what is used when they mount cartridges.
You are welcome to borrow it. Contact me off the thread/forum page and we can make arrangements. I have 3 different protractors and I can definitely say the Pro-Ject works great with "Pro-Jects". And it is easy as well.
By the way, I also have an Ortofon HMC-20 on my Vpi Scout. It is a very nice cartridge and I get excellent sound quality with it. I looked at the mounting holes on it and compared them to my Blue Point Special which is OEM with Projects. The Ortofon stylus is definitely further back and probably needs more "reach".
Keep working on it, it is definitely worth the effort and your ears will thank you. Your records too! |
HI Tom. That is very true, and the MintLp is not a universal-type protractor. The actual mounting distance of the arm has not been verified either. If that is off, everything is off. Sure, it will play, but not optimally. Project wouldn't be the first manufacturer to not mount their arm with any kind of precision. |
Thanx Hififile if I can figure out how to contact you off thread I will.
Measured everything today and sent photo to Yip. p2s is 212mm.
the measurement from pivot to the tip of the head shell is 235mm not the 230mm posted in spec.and the MHST on the HMC-20 is definitely 8.5mm. I played with the Mint some more last night(for about 2 hours) think I got things a little closer. so now it sits about a mm to the left at the outside or a point and a mm to the right at the other end.just doesn't ever land on both. I'll see what Yip says about the pics.
also Thank You to everyone for you help and suggestions it is very much appreciated |
Hi, Wilson667; hopefully things all work out with your Mint protractor. What is the distance from the vertical tone arm pivot to the center of the headshell slots? You should get something around 220-221mm if the effective length is correct at 230mm. (220.5mm + 9.5mm holes-to-stylus = 230mm)
I measured the distance on my Pro-Ject 9 aluminum 'arm and the center of the headshell slots is just over 220mm from the pivot, which is correct for a typical 9.5mm mounting hole-to-stylus distance. It could easily accomodate the 8.5mm distance of the HMC-20.
Tom |
As many of you know, but perhaps the OP does not, if the actual spindle to pivot distance on the table is not to spec, and if the Mint was built based on manufacturer's spec (rather than measured pivot to spindle), then the Mint will not be "correct". Since the stylus to pivot distance is "variable" in an arm w cart mounting slots, it really does not tell us all that much, unless there is a gross mismatch. |
Hi, Swampwalker; pivot to stylus distance is not really variable with the Pro-Ject 9 series tone arms. The headshell was designed such that installing a cartridge with typical mounting holes will put the holes at about the midpoint of the headshell slots and the stylus at the designed 230mm effective length. The slotted headshell allows for a range (~6mm) of cartridge mounting hole configurations but there is only one correct effective length for the intended alignment geometry.
If the distance from the pivot to the center of the headshell slots (~220.5mm) is grossly different for the OP's Pro-Ject 9cc tonearm, then the stated 230mm effective length may be in error. As to whether the pivot-to-spindle distance is grossly different than the stated 212mm, it's an easy task to measure that distance on the Pro-Ject 'arm. I get ~212mm with an aluminum 9 tonearm installed on a (Pro-Ject) mmf-7 turntable.
If Wilson667 takes a few quick measurements it may eliminate a couple of the obvious variables.
Tom |
Hi Tketcham
just wanted to add some info in hopes of finding a solution.All the measurements I have made on the Pro-ject 9C tonearm (carbon arm with attached aluminum head shell) are as follows:
Pivot to spindle, 212 mm
pivot to tip of head shell, 235mm
pivot to center of head shell slots, 228mm
cartridge mounting hole to stylus tip, 8.5mm
|
Dear Wilson667: Due that the pivot to spindle distance is fixed: 212mm then the pivot to to stylus tip must be ( Baerwald. ) 230mm and not 235mm as you have right now.
This means that you need to go back/rearward with the cartridge by 5mm and offset angle: 24°. In this way you will be right on target.
Regards and enjoy the music,
Raul. |
Hi Tom- I was talking pivot to spindle, not pivot to stylus. If the table has a fixed arm mount, or mounts directly to the plinth, that parameter is fixed. But OP seems to be telling us that the measurement of his table is right on the spec so that should not be an issue. IOW, never mind! |
Rauliruegas,buy my measurements 230mm is not possible, The center of the head shell sot is at 228mm the slot is 6mm long witch means I can only go back a max of 3mm putting me at 225 mm add the MHST of 8.5mm and I get an effective length of 233.5. please correct me if I am wrong |
Just curious, and I have a question.
Is there a way to verify the Arc Protractor itself, that it was indeed made to proper spec? Should there then be a specific measurement from center of Protractor spindle hole, to the Arc on protractor? Mark |
Dear Wilson667: That is something that you have to check " live ": I mean you have to measure ( you have to do it physically. ) the distance between the stylus and the tonearm pivot.
It is hard to believe that with that tonearm you can set up that cartridge: the overhang ( center of the TT spindle to stylus. ) must measure 18mm.
Now if the spindle to pivot distance is 212 and you can't get/match 230mm from stylus to pivot then you need a different tonearm or a different cartridge or you can make wider the headshell slot.
regards and enjoy the music,
Raul. |
Hi, Wilson667, have been gone this weekend or would have responded earlier. Sounds as if the tone arm MAY have been redesigned and the specifications have not been revised to reflect a different effective length of (perhaps) ~237.5mm. That's assuming that Pro-Ject still designs the headshell for a range of cartridge mounting holes-to-stylus distances. If the center of the slots is at 228mm plus ~9.5mm gives an effective tone arm length of ~237.5mm. The other assumptions are that the headshell offset angle has been revised to accomodate the Lofgren A/Baerwald alignment geometry and that Pro-Ject may have unfortunately failed to change the pivot-to-spindle distance to ~220mm to accomodate the revised effective length.
So many variables and so many assumptions. Not a good scenario.
My advice is for you, or the retailer that sold you the turntable, to contact Pro-Ject/Sumiko USA and ask about the apparent discrepancies.
Tom |
Agree w Tom. Something does not seem to be right. |
It sounds like the arm was positioned using effective length from spindle to pivot instead of spindle-to-pivot length (eff. length minus overhang). |
By the way overhang or more exactly a change in effective length of the tonearm via poor setup is not as important as VTA, VTA, anti skate or azimuth. Just a FYI. Do the measurements. The slight change in effective length / overhang can either result in increase maximum distortion or even increased overall distortion. But it also can result in reduced maximum distortion or reduced overall distortion and change your Null Point from Lofgren A to Lofgren B or otherwise or visa/ versa. If you run the distortion specifications the change might in fact be not dramatic.
But incorrect VTA can result in a major sonic compromise. So all the work to align HTA without correct VTA or otherwise is really for very little. After taking a sample of typical errors in setup and checking the resulting distortion figuress the results in fact are that different than the "prescribed" HTA of the arm in question.
Feel free to take me up on this but this can be mathematically validated.
So is the Mint or any other protractor that importaant. And that answer is it depends on the arm/ setup and more. |
