Paradise Builders

Jump to Latest
#2,023
Thanks to the generosity of pdul, I _think_ I now have enough transistors for a decent match. Let me know if these numbers will work:

Front end (for both channels):
20pcs NPN 520-539
20pcs PNP 560-579

Mirrors (for both channels):
10pcs NPN 410-429
10pcs PNP 410-429

Thanks!
 
#2,025
Speaking of organs...

This Telarc Michael Murray / Bach / Great Organ at Methuen is a good one.
 

Attachments

  • lenco_bach.jpg
    lenco_bach.jpg
    109.2 KB · Views: 379
#2,029
#2,032
hesener said:
thank you , looks great! I was looking at the cartridgeman "conductor" arm, doesnt have VTA adjustment though, and is more expensive....

The Cartridge Man Conductor Air Bearing Tonearm
Click to expand...

Thanks. That is a nice arm. I was fairly deep in my build when a used MG-1 became available with two arms, so I stuck an armboard at left rear of table. My initial plan was for a 12” Moerch DP6 I have.

Have you looked at the Trans-Fi Audio Terminator? The T3Pro sells for 770 GBP or $1175US. It has VTA.

Terminator Tonearm - Trans-Fi Audio

David over at Lenco Heaven likes it a bit better than the MG-1.

http://www.lencoheaven.net/forum/index.php?topic=2805.0
 
#2,034
For all those paradise builders out there - PLEASE REMEMBER TO ADJUST THE INPUT OFFSET with the trimpot right next to the input pins. You can do this with open input (just the DMM connected), and it will not be very stable, but you should be able to get it to below 100mV, and then you connect a 10k resistor and just move it a little bit to get it to zero.

Tried it yesterday, it makes a HUGE HUGE difference in terms of clarity, sound quality and sheer enjoyment.

In fact, my own (beta) paradise does not have input offset adjustment, and I was kind of getting used to the not so great sound apparently, but that experiment was a true eye-opener....
 
#2,038
Benedetto said:
Hi Alfred,
is there any news on the "oscillators" ?
Click to expand...

Please check out the updated assembly guides (links in my signature), these now have instructions on the amplifiers oscillating, the RIAA values, and the input offset trim.

Remember, only 1 (!) verified case of amplifiers oscillating... This should only be done when you really measure signals in the 70...100MHz range (and they are not coming from the radio station next door 😀 )
 
#2,039
hesener said:
For all those paradise builders out there - PLEASE REMEMBER TO ADJUST THE INPUT OFFSET with the trimpot right next to the input pins. You can do this with open input (just the DMM connected), and it will not be very stable, but you should be able to get it to below 100mV, and then you connect a 10k resistor and just move it a little bit to get it to zero.

Tried it yesterday, it makes a HUGE HUGE difference in terms of clarity, sound quality and sheer enjoyment.

In fact, my own (beta) paradise does not have input offset adjustment, and I was kind of getting used to the not so great sound apparently, but that experiment was a true eye-opener....
Click to expand...


Folks

Alfred talks about my boards. You are remember my problems:
Originally Posted by hesener
Hi Werner, can you confirm that the input voltage (measured at the input pins) is +2.5V, and the output voltage is +15V? How about VCASCH and VCASCL, and the voltages across the 6800uF caps?

Hi Alfred, I have just measured (Fluke 787)
UPLUS = -18,13
UMINUS= +18,13
INPUT = +2,48
OUTPUT= +15,23
VCASCH= +14,49
VCASCL= -14,56
Across the 6800 uF caps plus side +1,73
Across the 6800 uF caps minus side -3.16
EXI RIAA= +15,23

Alfred ask me to send the boards over to him for a check and he found
that I have forgot to adjust THE INPUT OFFSET . My fault😱. He adjust
it for me, measured all importend things, and told me that everything it
perfect now!!!
When I have the boards back in Ireland and Peters power supply is finished I will give same sound impressions.🙂🙂🙂
Alfred thanks a million you do a grand job and thanks to all other lads for help
 
You must log in or register to reply here.
Top Bottom