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回覆 (2284): Where did you find it ?
The truth is that there will always be compromise! The question is which set of comprise you feel is more acceptable! :-)  
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Well said  
 
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But some are less compromising than others, often time much less.  
kh33
13-04-11
10:39:09
回覆 (2286): Where did you find it ?
Already did a few rounds with one motor. The obvious is the instability when external vibration present.  
 
Two motors are much more steady. I also tried without the record clamp\weight. I like better lor !  
 
bobui
13-04-10
21:42:32
回覆 (2285): Where did you find it ?
You can run the Alphason on one motor and compare the difference !! @@
daiwok
13-04-10
17:02:17
回覆 (2284): Where did you find it ?
Lets wait for Dr invention.
bobui
13-04-10
15:48:26
回覆 (2283): Where did you find it ?
The truth is that there will always be compromise! The question is which set of comprise you feel is more acceptable! :-)  
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Well said
Derek2A3
13-04-10
11:08:21
回覆 (2282): Where did you find it ?
 
The truth is that there will always be compromise! The question is which set of comprise you feel is more acceptable! :-)  
 
 
thekong
13-04-10
10:36:48
回覆 (2281): Where did you find it ?
Alphason, which has 2 motors  
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If you apply a single power supply source to a two motors turntable. One motor happen to be spinning at 220rpm, the other one at 230rpm. The overall speed will always be balanced out somewhere between 220rpm and 230rpm. How steady the overall speed is cannot be determined by the difference between the two motors. Its always determine by how steady is the AC supply Hz and voltage for the two motors.  
 
Only the speed is determined by the variations of the two motors. Meaning if everything remain constant and you replace the slower 220rpm motor to a better motor that spin at 225rpm. The overall speed will always be balanced out somewhere between 225rpm and 230rpm.  
 
 
 
bobui
13-04-10
08:37:20
回覆 (2280): Where did you find it ?
 
>There is no point emphasis the problem of one when it only multiply/double when you have two. <  
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So, you mean your Alphason, which has 2 motors, actually has more problems than TTs with a single motor? :-)  
 
thekong
13-04-10
08:17:37
回覆 (2279): Where did you find it ?
 
the sunshine I mean  
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Always sunshine after CAS , sorry I mean rain !!! 8^)
daiwok
13-04-10
07:40:00
回覆 (2278): Where did you find it ?
when the set up speed for 33rpm is correct, it wont be when you switch to 45rpm. That I can understand.  
 
What Mark doesnt say is the problem associated with a two phase power supply.  
 
There is no point emphasis the problem of one when it only multiply/double when you have two.
bobui
13-04-09
22:20:56
回覆 (2277): Where did you find it ?
 
the sunshine I mean
evp1312
13-04-09
17:55:42
回覆 (2276): Where did you find it ?
evp1312
13-04-09
17:54:59
回覆 (2275): Calm before the Storm !
A 3-phase, 6-pulse inductance motor with 8-pole Neodymium magnets and 3 integrated Hall position sensors provides platter drive.  
 
Speed range includes 33-1/3, 45 and 78 R.P.M. User variable on power supply.  
 
 
daiwok
13-04-09
14:58:46
回覆 (2275): Calm before the Storm !
More from Mark Kelly on the subject:  
 
"For any motor which requires a phase faking cap, the value of that cap is dependent on the motor winding inductance and the drive frequency*.  
 
For any variable frequency drive which does not synthesise the quadrature pair, requiring the use of a faking cap, the value of the cap is correct for only one frequency. For all other frequencies the phase angle will be incorrect.  
 
* since the quadrature frequency is proportional to 1/SQRT(LC), for a change in frequency from 60 Hz to 81 Hz (eg 33 RPM to 45 RPM) the cap value would need to change by (81/60)^2 which is about 180%."  
 
 
 
thekong
13-04-09
14:58:14
回覆 (2274): Calm before the Storm !
 
Well, the following was according to Mark Kelly:  
 
"The single phase supplies (Walker VPI etc) require the phase faking capacitor to approximate the second phase to run the motor.  
 
BTW this means the quadrature angle will change with controller frequency making it unlikely to be correct at any frequency (and wildly off at 45 RPM).  
 
To avoid this effect by removing the faking cap you would need a two phase supply. The only commercial unit I can think of off the top of my head is the Basis (anyone know any others?)"  
 
 
Of course, I have no idea what this "quadrature angle will change " means, and how would it affect the sound!  
 
thekong
13-04-09
14:51:25
回覆 (2273): Calm before the Storm !
tried a Duelund yet ? @@  
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duelund is great but unfortunately they all have prostate problems.
drwkng
13-04-09
14:46:18
回覆 (2273): Calm before the Storm !
Sorry to learn about that lor! Tell your freind to go visit 1pk la! He would not have done such move if he has been active at 1pk lor! We can offer plenty of info for him.  
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I think he has learnt his lesson and went out and got one these !! yes he is the owner of Twin EMT 927 !!! @@  
 
daiwok
13-04-09
14:44:34
回覆 (2273): Calm before the Storm !
Too large for my handle, I have small hands!
bobui
13-04-09
14:43:31
回覆 (2272): Calm before the Storm !
And the answer is YES. Different phase caps do have an effect on the sound.  
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tried a Duelund yet ? @@  
 
daiwok
13-04-09
14:41:24
回覆 (2271): Calm before the Storm !
why talk about Belt drives ! puny motors ? @@  
 
Now for the big boys !! 16 inch !!  
 
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Yes size matters !!!  
 
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You got to have the whole family !!! 8^)
daiwok
13-04-09
14:39:10
回覆 (2271): Calm before the Storm !
To prove your point, Kong. One of the many playful thing I recently did to my Heybrook/Terminator when having it set up last week was phase cap changing.  
 
And the answer is YES. Different phase caps do have an effect on the sound. Probably speed stablity and lead to sound quality. I dont understand the full story behind but one thing I am sure of is ..........it actually is "FUN" to mess around with all the finest details in a turntable system provided if you dont get too hooked on it.
bobui
13-04-09
14:36:35
回覆 (2270): Calm before the Storm !
Yes Mr Holmes
bobui
13-04-09
14:29:12
回覆 (2269): Calm before the Storm !
Yes: If matching caps is so essential to the overall operational quality and sound and is no easy task. Then why on earth anyone want to build a two phase power supply when one can do with an add in cap between the red and blue!  
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my dear watson, money! money! money!
drwkng
13-04-09
14:22:14
回覆 (2268): Calm before the Storm !
was told that the phase cap has to match  
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Yes and No!  
 
No: Take Linn LP12 motor as an example. OK! The motor require 110V and there are three wires, red, blue and grey(two connected togther). The red is the hot which is connected to to the 110V ouput from let say a Valhalla. There is one cap of 0.22uf connect between the red and blue which is the phase cap. The grey wire is the return leg to the power supply.  
 
Yes: If matching caps is so essential to the overall operational quality and sound and is no easy task. Then why on earth anyone want to build a two phase power supply when one can do with an add in cap between the red and blue!  
 
Sometimes, "Less is more"!
bobui
13-04-09
14:19:34
回覆 (2267): Calm before the Storm !
 
>……also try out various phase caps to make improvement. <  
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I was told that the phase cap has to match (I am not sure whether it was the capacitance, or resistance, or something else) with the Hz for best performance. So it is a compromise with the normal single phase motor controller driving the same phase cap with different Hz for 33 and 45.  
 
That is one of the main reasons why a 2 phase controller is superior!  
 
thekong
13-04-09
13:51:41
回覆 (2267): Calm before the Storm !
I had a friend using the VPI SDS to drive his Thorens TD 124 ..... after about a month or so the VPI SDS died ! @@  
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Sorry to learn about that lor! Tell your freind to go visit 1pk la! He would not have done such move if he has been active at 1pk lor! We can offer plenty of info for him.  
 
Most 80s and 90s turntables were built around using a 24 poles AC motor of the Philips type or similar. These motors are small and only consume around 10W of power. Whereas in older type transcription turntables that were designed before the 70s mostly used much larger motors of 30W or above power consumption.  
 
There is a big difference between an 8 oz steak and a 32 oz Prime rib lor!
bobui
13-04-09
13:51:20
回覆 (2266): Calm before the Storm !
Nice, very nice looking turntable. Only wish I have more space at my den lor!  
 
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The Alphason has a pot to tune.  
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Yes, one trim pot to adjust the Hz (motor speed). The other one is for the output voltage. Lower voltage means less motor vibration. High voltage means high torque which some say can result into greater dynamic.  
 
 
Alphason Atlas is one of the very few that has a trim for Hz adjustment.  
 
To reduce vibration in any AC motor transcription turntables, you can lower the 240 or 110 V supply voltage by placing in a series of resistors and zeners. Because transcription turntables were originally used in studio or broadcasting where fast pick up speed is most desirable. The users didnt want to see a droping in speed when changing a record. So, the motors were mostly build like a tank with execss drive voltage to stablise the speed.  
 
For home useage, you can try to lower the voltage a bit and also try out various phase caps to make improvement.  
 
bobui
13-04-09
13:29:35
回覆 (2265): Calm before the Storm !
Simply Gorgeous !!  
 
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Let there be LIGHT !!!  
 
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and it spins !!!  
 
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daiwok
13-04-09
13:02:13
回覆 (2264): Calm before the Storm !
Warning ! do not look if you prefer to listen to music using a computer or touch screen. The images you are about to see require you to turn knobs and get your sorry ass off the chair to lift the needle up and down to change tracks and manually remove the and place the software ! this is not kids stuff !!!  
 
MINT CONDITION !!! @@  
 
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High Grade cable !! @@ what you find in old style rice cookers and steam irons !! 8^)  
 
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WARNINGS ON KNOBS !!!  
 
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so what is this ? @@  
 
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daiwok
13-04-09
12:59:54
回覆 (2262): Calm before the Storm !
 
I suppose he meant 2 phase (or is it 3 phase) motor controller!  
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i guess that much. it will be 2 phase to start with. adding a third phase would be simple enough. i'm going to use one chip amp to drive one phase. if it is not powerful enough, i can always parallel more chip amps.
drwkng
13-04-09
12:54:45
回覆 (2263): Calm before the Storm !
This is an older SME 20 power supply, the current flag ship SME 30 has a 3 Phase motor. Not sure about fine tuning as I guess must have a pot inside to tune. The Alphason has a pot to tune.  
 
I had a friend using the VPI SDS to drive his Thorens TD 124 ..... after about a month or so the VPI SDS died ! @@
daiwok
13-04-09
12:54:12
回覆 (2262): Calm before the Storm !
 
I suppose the SME 20 has a small motor, as the power supply is only 5 watt. The 30W VPI SDS failed to drive the Rockport motor!  
 
The SME brochure mentioned the speed could be find tuned, but I don't see any dial / trim pot on the power supply, so is it done inside the box?  
 
thekong
13-04-09
12:50:15
回覆 (2261): Calm before the Storm !
>Does it have 2 power supplies ?  
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what does it mean?<  
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I suppose he meant 2 phase (or is it 3 phase) motor controller!  
 
thekong
13-04-09
12:44:34
回覆 (2260): Calm before the Storm !
Does it have 2 power supplies ?  
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what does it mean?
drwkng
13-04-09
12:20:35
回覆 (2259): Calm before the Storm !
forget about this. just hold your breath for my superduper motor controller^-^  
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Does it have 2 power supplies ? BTW - we have a number of idler wheels which need around 100W power amp to provide sufficient AC to our motors.  
 
Your Lenco is still at my home .... and price is still rising Good Doctor !!!
daiwok
13-04-09
12:08:23
回覆 (2258): Calm before the Storm !
forget about this. just hold your breath for my superduper motor controller^-^
drwkng
13-04-09
12:00:39
回覆 (2257): Calm before the Storm !
Should be 50Hz on 33rpm
bobui
13-04-09
11:50:32
回覆 (2256): Calm before the Storm !
The Alphason has two motors. Not likely a problem for the SME as the philips motor current consumption is very low.  
 
1. Do you have a Hz measure. If so please see if the SME output is in 50Hz?  
 
2. Also please measure the voltage, Should be in the range of 80 to 110V. AC  
 
bobui
13-04-09
11:48:47
回覆 (2257): Calm before the Storm !
don't you love LP playback !! notice the direction of the arrow ! 8^)
daiwok
13-04-09
11:25:13
回覆 (2256): Calm before the Storm !
A new unit of current is born. this must be chinese clone^-^
drwkng
13-04-09
11:23:10