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Loss of quality sound pre to pre to integrated amp (signal loop)

Hififriend

Hififriend

pfm Member
Hello.
So I could not stand or bare to change pull out the RCA's when changing the source as there is only one Line Input at my beloved Sudgen headphone amplifier I now use as a preamplifier. So I had the idea to add a second preamplifier to have additional source inputs. (I hope it is clear)
So I connected a Rotel preamplifier RC-990 Bx (no current turned off not even mains in the socket)
which from Tape 1 Out goes into my headphone preamplifier Sudgen HA-4 (only 1 RCA input). From the Sudgen Pre-Out the signal goes in the Main In of a Rotel integrated amplifier RA-980 BX.

So now, instead of 1 source connected to the Sudgen (I like its sound), I have 3 sources: 1. Naim Nat 02 Tuner, 2. Turntable (Naim Stage Line N (phono preamplifier) to Hicap (power supply) in CD and 3. all the inputs from the Rotel RA-980 connected by Tape 1 OUT (Rotel integrated side) to the Aux IN (Rotel preamp).

It works fine but I wonder how much sound quality is suffering for example. Rotel CD player connected to CD input of the Rotel integrated amp RA-980 BX --> signal from Tape 1 OUT --> Rotel Preamplifier Turned completely off (Aux in) --> Sudgen preamplifier PRE OUT--> Main IN of the Rotel RA-980 BX

So instead that the signal goes: from CD --> (CD IN) Rotel RA-980 BX --> speakers, it goes
CD --> (CD in) RA-980 BX (Tape 1 OUT) --> (AUX IN) RC-990 BX (Tape 1 OUT) --> (Line INPUT) Sudgen HA-4 (PRE OUT) --> (MAIN IN) RA-980 BX --> speakers

1. How much sound quality loss ?
2. Why I can't connect a 4rd source in TAPE 1 IN at the Rotel preamplifier RC-990 BX ?

Manual says: Tape 2 out to Tape 1 in = ok (Tape 1 as a recorder)
Tape 1 out to Tape 2 in = NOT OK does not work (Tape 2 as a recorder)

Both Rotel preamp and integrated have no more influence, no more volume control- Integrated record selector has to be on CD (CD input) and Rotel Preamp record selector has to be on AUX (as Tape 1 out (int) goes to Aux in (preamp).

Recording selector shows only TAPE 1 and not Tape 2
But why there is nop sound when I connect a tape deck to Tape 1 in at the Rotel preamplifier RC-990 BX ???

Thanks a lot.
Only discovered yesterday that a signal passes through even when the gear is turned off, quite amazed by this. Looking forward for technical explanation. Signal loop etc

Kind regards.
 
Most (not all) amps simply switch whichever source is selected to "Tape Out", hence this is how it works here without power applied. problems with Tape inputs etc prob due to tape monitor facility. Keep vol at zero on unpowered amp for best results.
 
A lot of the rotel amps use a passive preamp just a volume control so it won't matter if its off, the phono stage is active obvously.


Pete
 
On amps that don't have a passive pre there could be issues.... my comment about keep vol at zero assumes a passive pre and was made for just this reason.
 
Hello.
So I just listened to turntable and it needs the preamp to be switched on, yes that's logic.
And the volume level is much lower if I connect the turntable with phono preamp and Hicap combo to the Aux in at the Rotel preamp compared to when I directly connect the turntable into the Phono entry (with Rotel phono stage) of the Rotel preamp. All other Rotel preamp inputs have an identical high level. Isupposed the Naim phono pre and the Hicap would level up the signal near to all the other line level inputs. But it's such a low level. Astonishing

For long listening turntable periods, I will definately connect the turntable - Stage line - Hicap combo directly into the Sudgen preamp.
Thanks for your answers but why the Tape 1 input on the Rotel preamp does not work, is it because of the Loop ? About passive preamplifiers, I do not even know if mine are active or passive, that is too technical for me.
 
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