xindak attenuation for using with leak stereo 20 help please
ive recently been given a xindak xa3200 mk11 and was wanting to use it with my leak stereo 20 but i can hardly get the volume on without it being very loud is it possible to attenate the lead from the pre to power without altering the sound quality and if so any advice would be great ie resistor values .ps i tried a 20 k pot but it seemed to alter the sound cheers again
ive recently been given a xindak xa3200 mk11 and was wanting to use it with my leak stereo 20 but i can hardly get the volume on without it being very loud is it possible to attenate the lead from the pre to power without altering the sound quality and if so any advice would be great ie resistor values .ps i tried a 20 k pot but it seemed to alter the sound cheers again
What is a xindak xa3200 mk11? If it's a CDP, build attenuation into the RCA plugs at the Leak's I/P jacks. Use 1/8 W. 1% metal film parts. It's the good old resistive voltage divider technique. 6.8 KOhm and 3.4 KOhm parts will give you 9.5 dB. of attenuation. That should provide some relief from the "hair trigger" volume control you're experiencing.
OK, the xindak is a line stage, not a CDP. That makes things more difficult.
The problem is too much gain, end to end. You can try a guitar amp trick. Please notice in the Leak schematic that the 2 sections of a 12AX7 are shared between both channels at the I/Ps of the amp. The amplification factor (mu) of a 'X7 section is 100. Other than a mu of 40, the characteristics of the 12AY7 are very similar to the characteristics of the 12AX7. Pull V1 and insert a 12AY7 in the socket. Use an inexpensive tube initially to get a feel for the effect on system volume and tone. If the effect is to your liking, buy a nice BVA made CV2650.
BTW, inserting a 20 KOhm pot. in the "hot" line is improper technique. The "ends" of a 50 or 100 KOhm pot. are connected across the "hot" and "cold" wires. The wiper gets connected to the "hot" center pin of the RCA plug. "Cold" is common everywhere. The inline attenuators should be placed very close to the power amp I/P jacks. The fixed resistance value ratio I previously provided will work, if you scale the values up to make the total resistance come in at approx. 100 KOhms.
The problem is too much gain, end to end. You can try a guitar amp trick. Please notice in the Leak schematic that the 2 sections of a 12AX7 are shared between both channels at the I/Ps of the amp. The amplification factor (mu) of a 'X7 section is 100. Other than a mu of 40, the characteristics of the 12AY7 are very similar to the characteristics of the 12AX7. Pull V1 and insert a 12AY7 in the socket. Use an inexpensive tube initially to get a feel for the effect on system volume and tone. If the effect is to your liking, buy a nice BVA made CV2650.
BTW, inserting a 20 KOhm pot. in the "hot" line is improper technique. The "ends" of a 50 or 100 KOhm pot. are connected across the "hot" and "cold" wires. The wiper gets connected to the "hot" center pin of the RCA plug. "Cold" is common everywhere. The inline attenuators should be placed very close to the power amp I/P jacks. The fixed resistance value ratio I previously provided will work, if you scale the values up to make the total resistance come in at approx. 100 KOhms.
Camperman, you have far too much gain. A CD player produces 2V, but the Leak only needs 120mV and you have added a pre-amplifier to make it even more sensitive. A 100k resistor in series with the input of the Leak, plus a 4k7 down to ground will solve the problem.
PS. Please use the "shift" key when posting on the forum. Posts without correct capitalization look poor and deter others from helping you. Thank you.
PS. Please use the "shift" key when posting on the forum. Posts without correct capitalization look poor and deter others from helping you. Thank you.
Thanks for that , ive now fit the resistors and its worked a treat ,i was wondering if you know what values to use when attenuating a cd input similar to russ andrews leads.I think its normally about 10 to 20 dbs of cut i would really appreciate your advice and im very greatful for your help so far .I would like to add the xindak pre amp was given to me by my best freinds wife he was killed in march in a motorbike accident so really am greatful for your help as i wouldnt have been able to use it without your advice cheers again 
Ive noticed that when i turn the volume up from 12 oclock[halfway] to full it hardly alters is this because the attenuation is to high .I have used 100k inline and 4k7 to earth in the plugs at the power amp end.Im guessing i need to alter the resistor to ground but to which value, sorry for the long delay but i dont usually play at this level of volume so ive only just noticed cheers again for your advice 
Thanks for that ive tried those values and it works but its not enough i can only get to about 9 oclock [ the volume starts at about 7 oclock ].Could do with something in between the two values if thats possible cheers. ps can you get phono plugs that you can plug another plug into the back of and put the resistors inside it ,and any ideas were from thanks for all your advice
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