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Ok so I installed a new cartrige, and most recently noticed that, atleast with certain records, I seem to have what I believe is rumble. Growing up in the digital era, and not being very familiar with the exact meaning and affect of Rumble, wow, and flutter, I must say I am guessing. But from what I have read, the intense motion of my speaker cones could be nothing else, correct? I dont generally hear anything from this I dont believe, but I do see it, and it concerns me. When I asked my father, he wasn't quite sure what caused it, but thought that a mismatch between my cartrige and tonearm might be the issue, as he remembered reading that certain cartriges were not recomended to him for that reason. I had never heard this, but was guessing that maybe a mismatch that raised the system resonance too high might cause that. Anyone have any information or thoughts on this.I currently have a Thorens TD125 MkII, ADC Tonearm, and an SME tonearm with issues. I get the excessive cone movement with both tonearms.
Follow Ups:
;^)
...regards...tr
If it isn't a cartridge/tonearm mismatch, and it isn't feedback or record defects, then perhaps it's been sitting too long and created a flat spot on the belt? I'd recommend checking for a belt flat spot or debris or wear and doing a good cleaning of the belt, pulley, and hub just to be sure. Cheers.
Its actually a brand new belt, and I did a cleaning when I put the belt on, about a month ago. It could be feedback, I dont know that it isn't for sure, and it could be record defects, as its more intense with certain records than others. One in particular has quite warp to it.
Hummm, then perhaps it is a borderline cartridge/tonearm mismatch afterall. I haven't looked at the other posts or the math and don't know if you'd need to decrease tonearm mass or increase it. But you could easily find out and increase it by adding a small bit of bluetac on the arm or headshell, rebalancing, resetting VTF to maximum recommended, and trying those warped records again if you're so inclined. Hope this helps.
Hi, and thanks again for the help. I feel like I am being difficult to even say this, but based on the math I did, using the VdH sight, I found the match to be perfect. Incase I did things wrong, Tone arm effective mass was around 7 grams, cartrige mass was around 5.5 grams, that meant I needed a high compliance cartrige. Cartrige compliance was around 20 or 25 (Cant Remember), which put my resonant frequency in the 8-9hz range.Now, I suppose that things could be mismatching regardless, I dont know, I really dont fully understand all the interactions that are taking place. Though I feel I did a good job mounting it, using an alignment protractor, test lp, and scale for setup, it might not be setup correctly. I dont know if certain aspects of setup could effect that.
I have heard varying stories about my main tonearm. The main one I use is the ADC ALT-1. Its a low mass tonearm that I was told was fairly unpopular when it came out more from being overlooked than being a bad product. I have heard that it was one of the best values in its day, to it is still a great tonearm. I have also heard that it was an utter piece of crud not even worth messing with. I have considered putting a tonearm like the Rega, or getting a restored SME tonearm, but would hate to waste that money only to find that it didn't fix this problem, which I now think it wont.
If by "certain aspects of setup" you mean alignment then I'd say no; I doubt that could be the problem even if you hadn't used a protractor. But vertical tracking force can SLIGHTLY change the equation (try it at different settings and see - usually higher is better).Some would say that 8-9hz is not the ideal range and the common recommendation is actually 10-12hz. But under extreme circumstance, such as an interaction with your thorens suspension, an even higher resonance might give better performance.
As suggested, I'd try tweaking the mass of the arm with bluetac/putty/etc and rechecking the woofer movement levels.
And also as suggested by the other poster, the thorens springs may need replacing or modding with foam aswell.
Sorry I can't give you a definitive answer. You may have to experiment a bit. Perhaps others like John Elison will chime in and provide you with more understanding or a solution. Good luck.
Ok so the specs for my arms and cartrige put my resonange at just around 9 and 10hz, which is perfect on the Van Den Hul graph. I think the arm and cartrige is a perfect match, so the problem may be other things.
The SME 3009III has an effective mass of less than 5 grams. It needs a very high-compliance cartridge to work. Are your other tonarms similar?According to van den Hull's web page, this would produce resonance frequences near or into the audible spectrum. Look at the graph in Appendix 2 and try to figure out where you fall. I'm not sure what the compliance of your Grado is in micronewtons per millimeter, you might have to research that.
> with certain records, I seem to have what I believe is rumbleIf your system is quiet enough--and yours sounds decently isolated--and your woofers go low enough, you will hear low-frequency noise enshrined in the grooves of many records. In many classical recordings made in Kingsway Hall, you get subway train solos every few minutes. Listen to LPs made in Boston's Symphony Hall and you'll hear trucks going through the gears on the street outside. Or, sometimes, rumble from a noisy cutting lathe will lurk under an entire side.
Point is, it's not always something wrong with your system--it could be quite the opposite, that you're faithfully reproducing a noisy recording, warts and all. It's either annoying or fun, depending on your point of view. Same with conductors who sing (ugh).
My guess is that engineers of the era didn't have monitoring equipment capable of reproducing this noise, and didn't realize it was being captured.
Great.
Yr rf should be between 10Hz and 15. That's the silent sector. Can't ehar them. Try to escape from them.
Check with test-lp.
Should be: Can't hear them...
1. Large bass-reflex speakers tend to move quite a bit at subsonic frequencies (where they are essentially in free-air). There is always some subsonic noise generated when playing LP's and it's just a natural by-product of pressing vinyl and the compensation curve of the phono preamplifier.2. You could be experiencing a cartridge/arm mismatch which may resonate at frequencies present in the recordings you're playing.
3. You could have a feedback problem, where bass vibration is picked up by the table and amplified again.
If the frequency appears to be very low and inaudible (woofer cones seem to wander randomly during play) then I'd advise adding a subsonic filter.
maybe i can answer this problem in layman's terms - after 35 years of setting up turntables, mostly good ones, my answer is: put a subsonic filter on your system, or get a preamp that has one. this is why great preamps of the past had them - all belt drive turntables rumble and grumble, god bless 'em, and even my big transmission lines don't suffer from a 17 cycle filter - beats wearing out the drivers for nothing
With what cartridge? That is the missing piece of the puzzle here. It could be called rumble I suppose as a mismatched cartridge and arm could accentuate that. It is as likely to be poor isolation and some vibration getting in from the outside. Rumble as expressed in a turntable spec would include only noise generated by the table itself and not external noise. Still noise is noise and any low frequency vibes are gonna cause the woofers to "rumble". A subsonic filter or a wall shelf would help if it is not a cartridge mismatch but an isolation issue.
-Bill
sorry, the cartrige is the Grado Sonata Refrence.It is isolated on tiptoe spikes, sitting on top of a 3" thick butcher block shelf connected to a rack that weights over 300lbs. Though maybe still not as isolated as a wall bracket, This is pretty well isolated, I have never had problems with footfall or anything of the sort. I am doupting its picking up noise from an outside source, but I wont rule it out.
The Grado is a pretty high compliance cartridge but it may benefit from a heavier arm still. The SME series II would be perhaps the most appropriate if that is what you have there. The series III is as or near as light as the ADC. Any edge warps will produce these results often enough as will the table suspension not been tuned properly. On an older table, it is possible the springs have some sag and could benefit from a stiffer support like new springs or some foam rubber inserts in the springs. If you can tighten the springs to make the table less bouncy that should help. You can test the arm weight (cartridge/arm mismatch) by loading the arm with some more weight. Simply wrap a few grams of weight around it near the headshell, zero-out the arm again and re-adjust the tracking force. If that cures it, the easiest fix would be to try another brand cartridge. The Grado sound is hard to reproduce with other brands though if you really like that. Maybe something as easy as a suspension tune-up and a whole armtube wrap would cure it and allow you to use the Grado. I have set-up an Lp12 here with a Grado a while back and didn't have any problems at the shop but I believe it had a Linn arm. Good luck.
-Bill
Thankyou, this was very helpful, I intend to take a final look now at the suspension tuning and see, I have actually never played with that. I even still have the bottom cover on, which I hear can affect the sound.I have considered changing the arm so many times. The SME is a series III, and like I said, has issues, I have taken it apart to clean, but the bearings look to be in bad shape, and even reoiling didn't make the arm move as smoothly as the ADC, which gives me pause to use it. If I was to decided to purchase a new arm for my table, do you think one designed around this basic idea, such as one of the Linn arms would be a good idea. I see people go nuts for the older SME arms, like the Series II, and they go for quite a bit of money, as much or more as many decent new ones.
Well, if it doesn't move as easily and it doesn't look good, I'd say that you are right. People do like the older SME arms as they are good quality and you can sometimes find them for a low price, but they are becoming more scarce and more damaged arms are showing up so it is a big risk buying used. If you can find someone that you trust and who stands behind the arm, like a dealer or even an inmate here that has a lot of nice feedback from others, maybe you will have a good chance of getting a better arm. I would get a series II if you do get an older SME as it is a medium mass arm and can be used with a wider range of cartridges. If you can afford an SME 309 it would be the bomb. A new Rega RB300 can be bought for that money with warranty also. People like all of these arms on the Thorens tables. I think the larger tube designs like the RB series and the 309 really offer the best sound for the money. Both are also medium mass designs. Getting an older sprung suspension to settle down in some environments can be a challenge. If you have a cement floor, you should have no trouble. I would also recommend a "sandbox" type isolation platform to replace the block of wood to help control vibration before it gets into the table.
-Bill
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