[RWP] USB audio device into Reaper

[Indigo]

I'm trying to connect my TC Helicon Play vocal pedal into Reaper, by 
USB; so I can plug a microphone into my eMu preAmp, instead of plugging 
the microphone directly into the vocal pedal.
I can only get the Helicon pedal to show up in Reaper's audio device 
dialog if I change the driver from eMu Asio; which the eMu preAmp 
requires; to Direct sound as the driver.
Luckily, the eMu preAmp's output section still shows up in audio device; 
after choosing Direct Sound; so I can set it as the audio input device; 
and also set the Helicon vocal pedal as the default audio output device.
With that setting, I can plug the mike into the eMu preAmp and hear it 
from the vocal pedal's headphone output.
Unfortunately, Direct Sound seems to cause huge latency, compared to asio.
I really don't understand why this Helicon vocal pedal just doesn't show 
up in the list of audio devices; along with the eMu interface.
The vocal pedal has its own USB driver internally, and Window's New 
Hardware Wizard installed it automatically, and said the device was 
ready to use.
So why the heck do I need to choose any driver for the vocal pedal in 
Reaper's audio devices?
Did anyone here ever try to run both a P S I E interface; like my eMu 
interface; plus a USB audio interface; like the Helicon vocal pedal, 
simultaneously; either in Reaper or in Sonar
Can it be done?

Plugging this vocal pedal into USB should be exactly like using a USB 
microphone.
It seems to me that I should be able to both run my P C I E eMu 
interface on its usual asio;  and also plug a USB microphone straight 
into a USB port on the computer.

I think every USB microphone has its own USB driver internally, and 
doesn't require choosing another driver in the audio device dialog of 
any daw.
The same should apply to this vocal pedal; when plugged into USB.
Any clues, anyone?
Thanks,
Indigo L