View Full Version : Jelco SA-750 Tonearm sound issues.
Hi guys,
I wonder if anyone can help me?!
I have just upgraded from a Jelco SA-250 to a 750D for my slate plinthed Lenco. I am using the same cartridge, an ancient Mayware MC-7V, and all other sundries from phono stage to cables are the same.
I won't say that I was expecting amazing things from this upgrade, but what I was expecting was, maybe, more of the same as I had been accustomed to with the 250 arm, but with perhaps a little more detail and refinement.
What I am getting, however, is a rather more hollow sound with reduced bass depth and impact, almost as if the sound is somewhat 'out of phase' or cart is mis-aligned. I have checked and double checked alignment, vta etc etc and am sitting here scratching my head as to why the sound I am getting is falling short of an improvement over my SA-250 arm.
Is the cartridge a mis-match or something? I am not very technical minded and I will admit that a lot of talk about 'compliance' and 'low mass/high mass' is all a bit beyond me so it would be much appreciated if anyone who cares to respond does so in a way that is very very simple (like me).
Any ideas guys?
Oh, also as I am aware that many of you will be unfamiliar with my cartridge, so I have attached some details from the Mayware flyer.
10285
Thanks in advance,
Frank
Hi Frank,
My first impression (after reading the specs of your cart) is that your cart's mass is a bit low for a 750D arm.
Ronald.
Clive197
08-08-2013, 11:04
According to specs. of both arm and cartridge there should no issues.
How old is the cartridge? Your description suggests stylus is worn and the new arm is highlighting the problem.
The previous tonearm was a lowish mass model with some liveliness to the sound as I remember - NOT a criticism by the way. I'd expect the 750 to offer more 'welly' to the sound, but since this is a 'feature' of Lenco's in general, I'm not sure :scratch:
The 750 has the option of a little pivot damping, which I'd recommend. What exit cables are you using?
Finally, I suggest one of Hugo's lovely bases for the 750, which seems a better 'fit' and locking for the arm pillar, as well as being finished to a very high standard.
Hope this helps a bit...
Hi Frank,
My first impression (after reading the specs of your cart) is that your cart's mass is a bit low for a 750D arm.
Ronald.
Thanks, but could you explain what this actually means and how I would go about rectifying the issue.
Frank
According to specs. of both arm and cartridge there should no issues.
How old is the cartridge? Your description suggests stylus is worn and the new arm is highlighting the problem.
Hi, I am pretty sure that the cartridge is not worn, but I plan to re-install it onto the Jelco 250 to make sure.
The previous tonearm was a lowish mass model with some liveliness to the sound as I remember - NOT a criticism by the way. I'd expect the 750 to offer more 'welly' to the sound, but since this is a 'feature' of Lenco's in general, I'm not sure :scratch:
The 750 has the option of a little pivot damping, which I'd recommend. What exit cables are you using?
Finally, I suggest one of Hugo's lovely bases for the 750, which seems a better 'fit' and locking for the arm pillar, as well as being finished to a very high standard.
Hope this helps a bit...
Hi Dave,
yes, this is essentially the point. I, too was expecting more 'welly' to the sound, but I am getting far less. In fact I would go as far as to say that the 'welly' that is a feature of Lenco's in general has all but dissapeared. This 'feature' was phenomenal last week when I was using the 250 arm :scratch:.
By 'exit cables' do you mean the ones from the base of the tonearm to SUT? If so, they are custom made ones. I do own the pink Jelco cable too, however.
Oldpinkman
08-08-2013, 13:58
Frank - if I have the right tech details, the cartridge weighs 6 gm (quite light) the arm has an effective mass of 21gm making a total effective mass of about 27gm and the cartridge compliance is 10cu. That puts the main resonance of that system (how bendy the cantilever is with how heavy the arm is) at 10Hz which is perfect. Think of a weight on the end of a fishing rod. If you wiggle it, you will find a frequency (wiggles per second - although Hz is the unit used) at which it is easy with very little effort to keep the rod wiggling. This is known as the resonant frequency. If you make that weight heavier, the frequency will get lower (slower). If the rod is more bendy (cartridge compliance) the frequency will get lower. The ideal frequency is about 10Hz. Above 20Hz you would definitely affect the normal sound hearing range (20Hz to 20Khz - for a youngster). Below about 8 Hz and it starts to cause problems with record warps and the like. Yours is bang on - so it ain't that.
Looking at it, whilst it is doubtless well engineered and good value, it ain't that different from a technics SL1200 arm, or a Linn Basik V, or any of dozens of decent very ordinary Japanese arms. So I am not sure which engineering feature, as opposed to marketing spiel, you are expecting to give you "welly". Sitting under a tree on my laptop, I am struggling with referencing both arms at the same time. There are threads if you google about the alignment being out on that arm. I believe it is a standard Linn mount. Have you checked the cartridge alignment at 2 points?
If welly means "bass weight" try a little damping. (Don't pick on me Geoff) . Not the damping in the arm (which affects that resonance we were talking about - which is NOT causing the trouble). Try damping the main tube resonance. Just temporarily try wrapping a rubber band round the tube about half way up. Maybe try a rubber band round the counter-weight too. Otherwise, I know its a pain, but reinstall the 250 to confirm it is the new arm and not some cartridge damage along the way (I speak as one who tears out cantilevers, puts a meter across the terminals and magnetises them - probably not an MC etc)
Thanks Oldpinkman,
some of that makes a little sense :lol:
I didn't think it could be a mis-match tbh.
I didn't expect it to give me 'welly' or more 'welly' per se, but I also didn't expect it to give me much less 'welly' than the cheaper arm. If anything I would have thought that it would at least be on a par. After all, it is supposed to be an upgrade!!
I do hear some extra detail and what some might describe as a little more refinement, but it sounds a bit odd to my ears, a little hollow, soft and lacking the drive and fullness that I have grown accustomed to.
I have a couple of hours free now so I am going to try a different cartridge before switching back to the 250 arm, will report back later.
Cheers,
Frank
Did you buy the 750D new Frank? I only ask because if not perhaps there is some play in the bearings due to wear or mistreatment which could be causing the issue you report.
Hi Dave,
I didn't buy it new, but it was advertised as 'nearly new' and I have to say it really does look it.
I have a sneaky suspicion that it may just have a slightly different sonic character/tonal balance, call it what you like, that just might not be to my taste.
This sort of thing has happened to me a number of times when I have attempted to 'upgrade' things.
Anyway, I just played a couple of tunes with the old arm and am about to re-install the 750.
My apologies if I have wasted anyone's time, but something very peculiar has happened.
I re-installed the 250 arm and found that, even though it lacked a little detail and refinement compared to the 750, my memory was correct and it sounded far fuller and with more bass drive. I only had to play a couple of tunes, it was so evident.
Here's the weird bit:
I re-installed the 750 arm and played the same tunes. This time, however, it sounded just as I imagined that it should. It had the fullness and bass drive of the 250 and everything else was better, more refinement, more detail etc.
Somewhere along the process of re-installation whatever was wrong previously has seemingly been corrected, even if I cannot say what that was. Perhaps the tonearm cable was not pushed in far enough or one of the tags on the cartridge was a touch loose, I really do not know. I am not sure that I care tbh, I am just so pleased that I am now hearing the arm as an 'upgrade' rather than a 'downgrade'.
Thank you everyone that tried to help and, again, my apologies if I wasted anyone's time.
Frank
Oldpinkman
08-08-2013, 16:53
Oh good - it's not just me that f***s things up when they install arms then :)
Oh good - it's not just me that f***s things up when they install arms then :)
You are not alone guys. I haven't actually managed to install an arm upside down as yet but I remain alert to the possibility... :D
Oh good - it's not just me that f***s things up when they install arms then :)
:rfl:
At least I learnt a thing or two from you Richard.
You are not alone guys. I haven't actually managed to install an arm upside down as yet but I remain alert to the possibility... :D
:lol:
I have to say, it is sounding bloody amazing now so whatever was wrong was seriously strangling the life out of it before.
Whatever it was I am glad it is now sorted, congratulations Frank :)
Cheers Dave. Btw are you still looking for a Jelco tonearm cable? I seem to remember you were a while back and I may have a spare one now.
Erm yes, but as usual when such offers poke their heads above the parapet my pockets are empty. I'm committed to spending this and next months hifi budget allocation on a set of IC's. If you still have them at the end of September let me know plz ;)
Thing Fish
08-08-2013, 17:53
Hi Frank, Glad the arm is now working as it should. It sounds to me like a loose connection somewhere along the line. Still as you say who cares.
What does your Bowie record sound like now? Great I bet...:eyebrows:
What does your Bowie record sound like now? Great I bet...:eyebrows:
:lol: How did you know I was playing that? I just literally finished listening to it now. As the kids would say 'it sounded amaze....' :)
Yeah, I am convinced that it was a loose connection, the tonearm cable not connected perfectly perhaps. Got some Joe Jackson on now, never heard it sound so good.
I reckon this setup would give your Ittok a run for it's money now mate :ner:
All right, it might not be quite that good, but I'd say it's close.
Erm yes, but as usual when such offers poke their heads above the parapet my pockets are empty. I'm committed to spending this and next months hifi budget allocation on a set of IC's. If you still have them at the end of September let me know plz ;)
Blimey, I thought you'd say 'nah, that was absolutely ages ago.' I'll see what I can do :).
Blimey, I thought you'd say 'nah, that was absolutely ages ago.' I'll see what I can do :).
I still don't have a Techie armboard for the Jelco so there's no rush as yet. All in good time ;)
Thing Fish
08-08-2013, 18:23
I reckon this setup would give your Ittok a run for it's money now mate :ner:
All right, it might not be quite that good, but I'd say it's close.
I dare say there are those who would argue that the Jelco is a better arm.
I still don't have a Techie armboard for the Jelco so there's no rush as yet. All in good time ;)
Which Jelco do you have Dave?
Ostensibly it is a 370h but with a 9" armtube. Jelco manufactured it for LAD to their specifications. Mine is fitted with a Shuggie mounting collar Frank :)
http://i1019.photobucket.com/albums/af316/Sgtgrash/4083fea9-3cc2-424f-8d46-65851b25122a.jpg (http://s1019.photobucket.com/user/Sgtgrash/media/4083fea9-3cc2-424f-8d46-65851b25122a.jpg.html)
Yes, I know the collar is the wrong way up, hence my comment about mounting arms upsidedown earlier :lol:
Nice!!
I remember that photo now, lol.
Clive197
08-08-2013, 21:38
Frank, glad the stylus was ok and your vinyl sounds all hunky dory.
Oldpinkman
09-08-2013, 06:20
One of these days I need to get you to hear a seriously good arm...:eyebrows:
Thanks Clive.
Yeah, if it had been the stylus I would have faced the prospect of sending it away to get re-tipped which, having just splashed out on the arm, I couldn't really afford right now. Anyway, played a few more records last night and it all sound splendid. :)
One of these days I need to get you to hear a seriously good arm...:eyebrows:
:lol:
Well, you are very welcome to send your Funk arm over Richard!! :eyebrows:
Idlewithnodrive
09-08-2013, 06:47
Must of been a loose connection Frank but as you say who cares ?
Audio bliss has resumed and that's all we need, simple folk we are :)
Cheers Mike.
Yeah, the new arm (now properly set up) is a definite step up from the 250, it really has taken things to another level.
Thing Fish
09-08-2013, 07:18
And what's the next level then Frank...:eyebrows:
Ha ha!! Well, let me see, get the arm re-wired with pure silver wire maybe?! Or perhaps a better phono stage?!
Oh no, now look what you've gone and done?!! :lol:
Oldpinkman
09-08-2013, 07:36
:lol:
Well, you are very welcome to send your Funk arm over Richard!! :eyebrows:
It's a rega mount . But of course I am split between 2 of them, and trying to get arthur to produce a third. I think, if I have understood "welly" properly, you would love the F5. There are things about the FX3 I love too much to turn my back on forever - but I like that "welly" from the F5. Mrs S is sold on the FX3. So - I need to get Arthur to build the FX3 with welly. He has the idea - and seems to think he can source the tubes, although I never understand how you can say "I want an arm tube spun from finest dragon gossamer" and just expect someone to manufacture one. Which is of course, why I am an accountant again :D
Hmm, they do sound good. And, I have a suitable armboard for a Rega mount Richard, you don't get out of it that easily!! :rfl:
Oldpinkman
09-08-2013, 12:27
Hmm, they do sound good. And, I have a suitable armboard for a Rega mount Richard, you don't get out of it that easily!! :rfl:
I fancy an outing sometime. It won't be before October, but one of my frustrations with this site (not a criticism, an appreciation of a constraint) is that lots of authoritative statements get made (we can think of a few about DaCapo) which don't accord with your own experiences, and there is no substitute for both listening to the same thing at the same time. So maybe that would be fun - I guess I could leave it with you for a week or two, as long as I can ponce another off Arthur to keep me going (and his prototypes are unsaleable, so if I can cope with their short-comings he should be able to spare them.)
Later - maybe :)
Meantime - to whet your appetite, having also posted this link on Radletts thread
http://www.tonepublications.com/analogaholic/review-the-funk-firm-little-super-deck/ (A review I know of because Arthur was having a mongy sulk about a couple of overseas distributors, who hadnt yet seen a deck, but had seen this review, asking for better setup instructions. Arthur gave me the box, and the instructions, and a filthy look, and said - "you have set up the arm on a suspended deck - set it up from scratch" and when I did, asked if I would write to the distributors to describe the experience. Of course - I am not sure he had counted on my house style for correspondence :lol:
Richard :cool:
I was only really pulling your leg Richard. But, having said that I wouldn't be totally averse to a get together. As you say, it could be fun.
It would probably be the only way I would ever get to hear a Funky arm. We could see if anyone else wanted to join us, within reason, it's only a one bedroom flat.
Anyway, we'll see eh?!
I'll have a little look at that review now.
Cheers,
Frank
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