Arnab,
Here are the answers:
1. RB 251 is an excellent tonearm, almost has become a standard, does the TT provides tonearm height adjustment? this is handy when one changes cartridge and its not from SHURE/ORTOFON
I do not think so. But one can use shims for this.
2. I have heard it has switchable 33/45, how is the drive and speed stability?
The Scheu tables are known for the drive and stability of speed. They use an inverted bearing which needs to be oiled before one puts on the platter. The bearing on the Cello is the same as their higher model Premier and Premier II which have much heavier platters. The oil comes in a syringe, all supplied with the TT. Instead of a rubber belt, they use a very thin nylon thread. The TT comes with a 200m reel of this thread. Scheu thinks that this is better sonically than rubber belts, because it is presumably more difficult to make rubber belts with low tolerance with respect to climate changes. The platter is made of acrylic and is made using the same material and precision (flat up to 1 in 100) as that of the Premier. But on the Cello, the platter is lighter, because the plinth is also perhaps lighter.
3. Did you notice any inner groove distortion? I have found it to be common in almost all TTs (some higher some lesser) no matter how you deal with it
So far I have listened for an hour to 75 minutes. I have so far not used any high quality vinyl records. But with the ones used last night, I did not find any noticeable difference with inner tracks. This depends quite heavily on the cut of the needle. Instead of the stock Super OM 10 which has an elliptical cut, or the Super OM 20 (with a nude elliptical cut), I chose the Super OM 30 just because of its nude fine line cut. This should track much better the inner grooves. I have serious budgetary constraint, but if I find something necessary for me, I will cut somewhere else in my expenses, and add the necessary bit. In this case, that meant an additional expenditure of over 10K including VAT. But in my judgment, it is money well spent. Time will tell.
4. whats the platter weight?
The platter weighs 2.5 kg and is 30mm thick. One is not supposed to touch the platter with bare hands to avoid finger-printing. Scheu puts in a pair of cotton gloves in the package. The gloves look exactly like the inner gloves used in cricket (mostly by wicketkeepers, but also used by a few batsmen like Rahul Dravid).
5. I guess the operations are fully manual for such a high-end TT?
I would not call it a high end TT. However, it is starting to be a serious minded TT from this point onwards. The thinking behind it, I suppose, pays attention to some of the basic things in building a good TT. Yes, all operations are manual. and I like it that way. I will pay for the sonics and build quality, and not for anything else. My Leben amp does not come with a remote, my CDP has a remote and I do not use it. The only remote I use is for the TV, because I have a habit of changing channels.
you should compare it with a popular entry level TT in terms of sound stage, attack, ability to reproduce more quieter moments, momentary thump, deep and detailed bass response, natural voice reproduction.....
It will be difficult to do this comparison. People around do not have entry-level TTs. Vasu has the VPI classic, Pratim has Pro-ject RPM 4 and Manoj has a Rega P5. Only Pratim's is the closest to an entry level, but much better than a Genie or a Debut. In addition, I would not request any of them to bring their TT over (because transporting a TT is not the most trivial thing, one has to do it carefully and the packing & unpacking hassles may not be worth it). But we will have a fairly good idea about my TTs true capabilities in a few weeks once it burns in and I have a few phono stages to try. But the starting impression is good.
why do you want to change 640P? are you not satisfied with it? I have found it to be incredibly VFM though I have no experience of more costly phono stages
I agree that the CA 640p phono is VFM. Actually just after I bought it, within 10 hours at the most, the motor of my Dual died. So, even the phono is not properly burnt in. I want to give everything at least 30 hours and then start making the first solid impressions. Given all that, there are better phono stages in this world. I will have to see if the improvement is significant to my listening ears given the extra money of the other more expensive one (of course one has to keep also in mind that the improvement is not a linear function of money spent). Whatever I buy is hugely driven by VFM considerations. This includes my CA 740c CDP and even my Leben amp. I hope this TT turns out to be one too.
one more query - is for the OM series the cartridge body is same and the needle changes or the whole cart-needle assembly is different for OM10/30?
Do not confuse OM with Super OM. There was also an OMB series. My Dual CS5000 came with the OMB 20. The Super OM is now replaced by the 2M series I think, but is still available in Europe directly from Ortofon. The OM series was a much earlier series. But, to answer your query, I think all Super OM (and the earlier OM and OMB as well, I think) bodies are the same, it's only the needle that is different. However, that is not completely true for the recent 2M series. The Red and the Blue have the same body, and the Bronze and the Black have an upgraded body. I hear that the Red is good, but the Blue is the real VFM, and if you have money, go for the Black. It's the best MM ever made - according to many, and performs and costs way over many MCs.
Regards.
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