Lenco demonstrator

Subjects that don't have their own home
User avatar
cressy
Shed dweller
Posts: 2906
Joined: Fri Aug 03, 2007 7:07 pm
Location: the great white space
Contact:

#121 Re: Lenco demonstrator

Post by cressy »

Interesting looking clamp that one, think it would be a pig to make one though.
Fitted the shure m97 to the deck with a new stylus.
I prefer it so far with the brush down, quite a musical cart. Should get a bit better, and shouldnt chew up my records.
Next, i need to plumb in the micromega phono stage
But not right now, first I need to sort out an annoying buzz from the power amp transformers......

Also found some 10mm thick pieces of slate in my tool cupboard that look spot on to cut some circular arm boards out of........
User avatar
cressy
Shed dweller
Posts: 2906
Joined: Fri Aug 03, 2007 7:07 pm
Location: the great white space
Contact:

#122 Re: Lenco demonstrator

Post by cressy »

Couldn't wait to try the micromega, its a real smoothie.
The xlps is a little harsh in the treble, the micromega isn't.

Its nice and clean, imaging straight out of the box is better.

Quite happy with that.

Oh, and realised that the right hand channel was wired backwards, i.e green to red pin, red to green pin on the back of the cart. So one channel was out of phase with the other. Shure in their infinite wisdom have the pins arranged with one channel upside down compared with the other and I could only see one side of the cart when i put it on.
Rather better wired properly
User avatar
cressy
Shed dweller
Posts: 2906
Joined: Fri Aug 03, 2007 7:07 pm
Location: the great white space
Contact:

#123 Re: Lenco demonstrator

Post by cressy »

Another shot of it from a better angle. Its surprisingly difficult to get a decent pic of it for some reason.
Image

Need to sort some packaging out......
User avatar
cressy
Shed dweller
Posts: 2906
Joined: Fri Aug 03, 2007 7:07 pm
Location: the great white space
Contact:

#124 Re: Lenco demonstrator

Post by cressy »

Starting to get a handle on the m97 now, I tried a vta change by shimming the arm up at the pillar with some 1mm washers under the 3 mounting points.
Such a pain in the arse to do, I still can't fathom what rega were thinking with the 3 point mount and lack of a rudimentary vta adjustment, but hey ho.
Its about right now, was a little dull before with some bass bloat, the vta change has alleviated most of it. both the new stylus and the micromega phono stage have only got about 10 hours on them though so we shall see
Last edited by cressy on Fri Dec 02, 2016 9:22 am, edited 1 time in total.
User avatar
Greg
Social outcast
Posts: 3198
Joined: Wed May 23, 2007 11:14 am
Location: Bristol, UK

#125 Re: Lenco demonstrator

Post by Greg »

cressy wrote:Such a pain in the arse to do, I still can't fathom what rega were thinking with the 3 point mount and lack of a rudimentary vta adjustment, but hey ho.
Yes, simple stupidity IMHO. Actually, any arm without ready VTA adjustment is a nonsense. I have ready VTA adjustment. One of the reasons why I enjoy my Audiomods :bounce: :bounce: :D
User avatar
cressy
Shed dweller
Posts: 2906
Joined: Fri Aug 03, 2007 7:07 pm
Location: the great white space
Contact:

#126 Re: Lenco demonstrator

Post by cressy »

Apparently rega don't believe in it.
What is it then? Imaginary?
Having a stock rb250 here and the almostarega modded thing to compare side by side it looks simply to be a cost cutting excersise. The 250 has the turned and threaded brass pillar with pressed in bearings for the yoke, the other one has a plasic molding with the 3 point mount and pillar cast in one and a short brass tube about 1/4" diameter and I think 2 bearings forming the lateral bearing.

Theres absolutely nothing wrong with plastic when used based on its properties, as it is in this case, its not the 3 point mount per se that i have a problem with, its the fact that they made it so much more difficult for the 251 to be adjusted for vta, and infact completely mugged it off as a pointless adjustment that didn't need consideration when redesigning the pillar.

If they had simply cast the pillar in plastic, threaded it and supplied a pair of nylon nuts, one for the top of the plinth that looked nice to set the height and one underneath to lock it, it would have been so much more versatile.

Infact, i think I have a 22mm die somewhere, might try it, the pillar casting is plenty thick enough to take a thread..........
Still want an audiomods arm though......
User avatar
Ali Tait
Eternally single
Posts: 4374
Joined: Fri Jun 08, 2007 8:10 pm
Location: Galashiels

#127 Re: Lenco demonstrator

Post by Ali Tait »

Looks the biz Ant.
User avatar
cressy
Shed dweller
Posts: 2906
Joined: Fri Aug 03, 2007 7:07 pm
Location: the great white space
Contact:

#128 Re: Lenco demonstrator

Post by cressy »

Yet another change today, I was getting quite abit of hum from the micromega phono stage that i couldnt cure so i made up a new arm cable using a length 4 core shielded cable from maplins. Already had a spare din plug as I bought 2 when i made the original one, just had to get some more plugs for the other end.

The hum is now pretty much cured on mm

The casing for the phono stage is plastic so its not shielded by the case unfortunately. Haven't tried it on mc though...
User avatar
cressy
Shed dweller
Posts: 2906
Joined: Fri Aug 03, 2007 7:07 pm
Location: the great white space
Contact:

#129 Re: Lenco demonstrator

Post by cressy »

Took the micromega out to give the nuvistor phono stage I built God knows how long ago a try it with a moving magnet cart.
It pissed all over the micromega. And the musical fidelity.
I never used it with an mm cart, i havent had an mm cart it 10 years at least, so always used it with step ups and various mc carts. Which was abit silly in hindsight as it was originally designed to be used with the sowter suts I had at the time, so essentially it is an mm phono stage.

It mullered both the solid state phono stages.

Bear in mind that the micromega is 129 quid new and the xlps was about that new, then this might not really be saying much, but i was very surprised by how marked the jump in quality actually was.

Thinking on, the thing was built set to a 47k input impedance, and mcs usually want around 100r, but with a sut on the input God knows what the input impedance was.

Happy i got a little bit of the glow back too :D
User avatar
pre65
Amstrad Tower of Power
Posts: 21373
Joined: Wed Aug 22, 2007 11:13 pm
Location: North Essex/Suffolk border.

#130 Re: Lenco demonstrator

Post by pre65 »

Was there a thread on your nu-vista phono stage. ?
The only thing necessary for the triumph of evil is for good men to do nothing.

Edmund Burke

G-Popz THE easy listening connoisseur. (Philip)
User avatar
cressy
Shed dweller
Posts: 2906
Joined: Fri Aug 03, 2007 7:07 pm
Location: the great white space
Contact:

#131 Re: Lenco demonstrator

Post by cressy »

Here we go
http://www.audio-talk.co.uk/phpBB3/view ... hono+stage

It actually goes further back than that as it was originally designed for the 7f8w

The circuit hasn't changed much other than the output cap which i think is something like 2.2uf, but the psu has been buggered about with. I think its something like 225v now.

It does need putting in a metal box, tbh i think the only other people who have heard it are simon and mi dad as I took it to simons in the summer
Ant
Shed dweller
Posts: 2332
Joined: Mon Jul 31, 2017 6:45 pm
Location: Yorkshire

#132 Re: Lenco demonstrator

Post by Ant »

Did a little long overdue work on the demo Lenco today. It was getting abit ropey, having being bashed about and messed with so I gave it abit of love, tightened up some loose nuts and bolts, readjusted the on off linkage, and did some jobs such as putting abit of thread lock on said loose nuts and bolts that I should have done when I built it.

Also turned an arm mount up so I could fit the audio technica AT1100 arm wot I got recently.

This arm is fab. I think iv'e found the arm/cart combo I have been looking for

ImageLenco + audio technica at1000 + at 150sa by anthony cresswell, on Flickr

It is so very fast and detailed sounding, bass is exactly how I want it, tight and deep without and flabbiness, mid and treble are spot on. Lets the high comp at150 do its stuff.

ImageLenco + audio technica at1000 + at 150sa by anthony cresswell, on Flickr

It just sounds right.
Right enough that I felt the need to play almost there off Level 42 again once the side had finished.
When they say "they don't build em' like that anymore" they were talking about this arm. It suits the AT150 very very well, and probably the AT440 mlb I have on the jvc too
Well impressed
Also starring Rex Hamilton as Abraham Lincoln

www.bte-designs.weebly.com
User avatar
Mike H
Amstrad Tower of Power
Posts: 20157
Joined: Sat Oct 04, 2008 5:38 pm
Location: The Fens
Contact:

#133 Re: Lenco demonstrator

Post by Mike H »

Altogether now.....

"Shoddy!"

Congrats Image
 
"No matter how fast light travels it finds that the darkness has always got there first, and is waiting for it."
Ant
Shed dweller
Posts: 2332
Joined: Mon Jul 31, 2017 6:45 pm
Location: Yorkshire

#134 Re: Lenco demonstrator

Post by Ant »

Checked back over my build notes (yes i am a sad twat, but it does come in handy down the line) for the deck to see what id done to the motor, bearing ect.
Turns out id replaced the motor with a working one but had just dropped it in and not rebuilt it.

According to the build notes, i'd wrote " feels ok, no drag, rebuild?". Then lost my rag with it when it wouldn't drive properly and left it.

So ive pulled it apart and rebuilt it, its quietened it down some and also removed an annoying ticking it had developed.

Much betterer
Also starring Rex Hamilton as Abraham Lincoln

www.bte-designs.weebly.com
Ant
Shed dweller
Posts: 2332
Joined: Mon Jul 31, 2017 6:45 pm
Location: Yorkshire

#135 Re: Lenco demonstrator

Post by Ant »

Did some more build note checking today. I fitted an audiosilente cnc idler wheel to it when I built it as there was a huge wobble on the original one. and as it needed to be run in, id used some lithium grease instead of oil to make sure the lubricant stayed where it was.
What i should have done was leave it for a week then pull it apart and redo it with proper oil once it had bedded in.
Didn't do that according to the notes :roll: .
So ive done it now.
The grease fine worked for bedding it in, when Ive inspected the bore on the idler its spot on and polished, all machining marks are gone. The 2 ptfe washers that go either side of the bush are also polished on the idler side faces, all the casting and stamping marks have gone too.
Having cleaned off all the remaining grease and rebuilt it with light machine oil it spins much more freely with no movement or noise. I also replaced the tyre with a new one as it was looking abit ropey.
Better again.

I also had another look at the arm as something has been bugging me. It has low set bearings and is supposed to be set up with the bearing centres in line with stylus. Like the cx unipivot wot I built.
As it was, to get the right vta, pillar was set with the bearings about 3mm low, so I cut a shim out of some 3mm perspex and stuck it onto the underside if the headshell with some double sided tape. Put the cart back on, and the bearings are now on the same plane as the stylus.
Sounds better again, something snapped into place and its more natural
Got some work done this morning before all this, so had a productive day for once
Also starring Rex Hamilton as Abraham Lincoln

www.bte-designs.weebly.com
Post Reply