UcD400 and high level sub input

[chrisb03]

Sorry if this has already been asked, I did a search but could not find a answer to my question.

I have build a Ucd400 two channel amp in the past. They currently drive a pair of Sonus Faber Concerto. I have a cd player supplying spdif to a P3A DAC which then goes to the amp via a passive volume pot.

I bought my self a sub today and trying to work out the best way to setup.

Can the UcD400 drive the Concerto's and also supply high level signal to the high level sub inputs? Is the UcD ouput stage ok for this kind of setup?

I would prefer to run an active cross over but can't afford one, unless there is a nice high quality kit available.

Chris

 

[kASD]

Why donot you use Line level inputs of Sub???

 

[chrisb03]

I don't have any outputs on dac. Are you saying I should parrallel the line level outputs from the DAC to go to both the UcD and Sub?

 

[kASD]

I don't have any outputs on dac. Are you saying I should parrallel the line level outputs from the DAC to go to both the UcD and Sub?

Yes you could parallel....what is the output impedance of your dac

 

[chrisb03]

Output impedance is 100 ohms, but I have the passive volume pot on the output. I would be parralleling after the pot. I can't remember what size pot I have, it's about 10K

 

[kASD]

Parallel before pot and adjust the sub level accordingly....

 

[chrisb03]

That would mean I would have to adjust the sub volume at the same time I adjust the passive pot volume. That doesn't make sense.

 

[kASD]

hahaaa, ok then what is the input impedance of your UCD and sub...

 

[chrisb03]

ummmmmm... don't know.

Am I missing something here. I'm not sure I understand. Are you saying depending on input impedance of ucd and sub that the signal going to sub will adjust linearly with the pot even though it's connected before the pot?

 

[kASD]

No you misunderstood....

Ok, if you have access to say 1K-5K pot then you could able to connect both UCD and SUB after the pot....

 

[chrisb03]

Just pull it apart, it's a 10K pot.

 

[kASD]

Could you get a 1K or 5K pot.....

 

[kASD]

Are you using a single or dual pot?

 

[chrisb03]

Single pot, why does it need to be 1k-5k?

Sorry for the stupid questions, I built this amp a long time ago and I have forgotten the research I did to figure out size of passive pot.

 

[kASD]

I love tinkering with newbies...
No need for 1K-5K pot if its single....
You can connect a dual pot and use each half pot for sub and another one for ucd, but you have to use 2 dual pots or a single 4 gang pot for stereo....to control the volume from one knob...

 

[chrisb03]

I love tinkering with newbies...

No need for 1K-5K pot if its single....
You can connect a dual pot and use each half pot for sub and another one for ucd, but you have to use 2 dual pots or a single 4 gang pot for stereo....to control the volume from one knob...

I need to draw a circuit to understand.

 

[kASD]

I need to draw a circuit to understand.

ok draw the circuit.....

 

[chrisb03]

Does it matter what size the pots are now?

 

[kASD]

Does it matter what size the pots are now?

Good Connections.....

10K maximum

 

[chrisb03]

I haven't checked lately but a high qaulity 4 gang pot probably cost me over $60 australian, for $180 aus I can get one of these

http://www.behringer.com/02_products/prodindex.cfm?id=CX2310&lang=ENG&CFID=13429