Reduce line levels of Uphorik and Klimax DS

[dvdr]

Hi - I have a wonderful vintage tube-amp from Unison and a vintage Revox tape, which I want to connect to a Uphorik and KDS. But: line levels are too hot. As per Linn docs:

Uphorik: Maximum output voltage 12 V RMS, 17 V Peak, +21.6 dBv (measured signal to screen)
Output Impedance: 600 Ω

KDS: Analogue Output; 4 V RMS
Output Impedance: 300 Ω“

Unison’s volume control at below 8 o’clock already is way too loud and the Revox also seems to be close to overloading the inputs. As per datasheet, the latter has an input sensitivity of5

50 mV @ 100kOhm;
Max. input level 2,5 V

So I will build a simple “voltage divider” using high quality Vishay resistors. But I need the proper values for this -20dB attenuation that properly matches both the output impedance of the Uphorik/KDS as well as the input impedance of the Unison (which I don’t know, guessing it to be in the 47k - 100k range) and the Revox as well as having no considerable interaction with the capacity of the Linn cables.

I found way too many suggestions for these kind of attenuators on the web ranging from 1k/100 Ohms to 100k/10k - all claim some “matching reason” for it and say, the other examples are wrong.

Thanks for helping!

 

[Nopiano]

Can you not reduce your KDS’ output at line level using your Linn account?  It may be in Konfig too, but I rarely look at that. My Akurate details on the web Linn account look like this screenshot.  

The unbalanced outputs are typically 2 volts maximum, aren’t they?  The 4 volts is for balanced.  

 

[dvdr]

Can you not reduce your KDS’ output at line level

No, not possible with the KDS/1, neither with the Linn account nor in Konfig. It’s fixed unity gain (which I need) or digital volume control. 
So I need classic passive attenuation -   RCA outputs go to my Klimax Kontrol/Klimax320a, balanced outputs of Uphorik/KDS will be adapted to RCA and go to the Unison/Revox. Btw.: even unbalanced RCA outputs of the Uphorik would be “too hot” for the Unison (like the Revox seems to be classic 0.775V design).

 

[Nopiano]

No, not possible with the KDS/1, neither with the Linn account nor in Konfig. It’s fixed unity gain (which I need) or digital volume control. 
So I need classic passive attenuation -   RCA outputs go to my Klimax Kontrol/Klimax320a, balanced outputs of Uphorik/KDS will be adapted to RCA and go to the Unison/Revox. Btw.: even unbalanced RCA outputs of the Uphorik would be “too hot” for the Unison (like the Revox seems to be classic 0.775V design).

Oh, I’d thought the DS models were all similar. Even my old Sneaky could adjust the line out!  I’ve no expertise in the values you’d need to make your own ‘voltage divider’.  All I’d do is ring up Rothwell, who are experts in attenuation. 
 

However, on the main forum, a number of Wammers build their own kit, so somebody might be able to help.  Here’s the DIY section…

https://www.hifiwigwam.com/forum/forum/19-diy/