[flintstone]

If your cdp has 2v output and it takes 2.2v to drive your amp to full power, would the 6db gain option be a good idea?. Speakers are on the low (87db sensitivity) side.

CDP-Pioneer PD-65@2v output
Krell Ksa-250@ 47,000 ohms input impedance/2.2v for full output
Thiel 3.6@87db sensitivity and impedance of 2-4 ohms

Does the 6 db gain impact sound quality in any way? Will this system have fair-good volume and impact with these speakers?

Thanks for any help
Dave

[John Chapman]

Hello!

I think with those modest (and lower than typical these days) sensitivity speakers I'd put the +6db switch in as a just in 'case' measure. Most all the time you'd not engage the switch I'd guess.

I don't think it really impacts the sound to add the switch but I am a 'min path' kinda guy so most of the time I leave out the switch if it appears that the system has lots of gain. An easy test is to plug your cd player right into your amp and play a selection that builds very slowly (or you may get hit with a speaker cone!). This level would be the 0db level and +6 would be louder. This will give you a sense of the max volume you'd get with a passive using that source, amp, and speakers.  For the times you need to go to '11' the +6 db switch would be there.

The tx102 does not measure quite as well when used in +6db mode but I have to confess when I have tested pre-amps with the switch here I have a hard time telling when it is engaged - it is very close in sound.



Thansk!

John Chapman
www.bentaudio.com

[flintstone]

If I understand you John, Do you mean that as long as you do not engage the switch..it has no effect on the signal (sound). For those times when it would be used it would (could) have a small effect? If this is the case then that would seem to be the safe way to go in this system.

The reason for my asking is, I got an e-mail from a guy from the Audiogon forum asking for advice..I don't know the guy but he took a look at my posted system on that forum. I have a Bent TVC and I also have the Krell Ksa-250 amp..my speakers however are 91db sen. My Sony cdp is also 2v output.

My system plays plenty loud for me but I have different speakers so I was not sure if he might have a volume problem.

Dave

[John Chapman]

Hello!

When the +6db switch is not engaged it still adds a switch contact to the signal path and I am sure has some small effect on the sound - as everything does. That's why I leave the switch out whenever we are sure that there will be lots of gain. If there is some concern then it is worth putting it in.  The cd player direct test should pretty much answer the max volume issue. Just be sure he does not do the test with the telarc 1812 or he's likely to get beened in the head with a speaker cone! Another way to guess the level is that In rough numbers the level you get when you are 2 steps down from the top level is the level he'd get with the volume right at the top (without the +6 db gain). Also with +6 his system would go louder than yours would with the level control all the way up. Just out of interest - What is the loudest level you'd listen at?  

Thanks!

John

[flintstone]

My speakers are Vmps Supertowers (4 ohm and 91db), these are large 200lb. each 8 driver system.  My room is 27X23 and 90% of my listening is between 10 and 2 on the dial. My cables are Harmonic Tech truth-links, 1 meter single-ended between Cdp and Bent/2 meter balanced run between Bent and Amp.

I sent an e-mail asking for his room size and volume level he listens at most of the time.

Thanks, Dave

[flintstone]

I should have added that I sometimes go to three O'Clock for loud rock type music.

Dave