An experiment in amplification

[Mikeandvan]

If it sounds good. Leave the bloody thing alone.

S.

An extra power supply at least?

[Haselsh1]

Question: What if the gain controls on the two Crown amps are input attenuators..? What if they attenuate the signal coming in..? If that was the case then it should be possible in theory to connect the CD player directly and adjust the input level via those two controls..? Not ideal maybe as I would prefer to have a preamp but possible..?

[Haselsh1]

The input sensitivity is set to 1.4 V on each amp with both amps set to bridge mode. The gain controls are currently turned down about five clicks each. I appreciate Martin's comments about a passive preamp and other's comments about attenuators. At the moment I rather like my PrimaLuna preamp due to the possibility of using remaining vinyl at some point but at least I have a few options to follow. Thanks you guys.

[Macca]

Question: What if the gain controls on the two Crown amps are input attenuators..? What if they attenuate the signal coming in..? If that was the case then it should be possible in theory to connect the CD player directly and adjust the input level via those two controls..? Not ideal maybe as I would prefer to have a preamp but possible..?

Yes you could do this but two caveats - first the direct connection may have an issue with impedance matching. So it will sound crap. That's always been my experience with connecting directly to a power amp with variable gain but it is worth a try. Second it may be that the power amp only gives best performance WRT distortion if the variable output is set to full - as with the Behringer A100 for example.

[Haselsh1]

Yes you could do this but two caveats - first the direct connection may have an issue with impedance matching. So it will sound crap. That's always been my experience with connecting directly to a power amp with variable gain but it is worth a try. Second it may be that the power amp only gives best performance WRT distortion if the variable output is set to full - as with the Behringer A100 for example.

Martin, I tried a Behringer years ago and it was so bad it was unusable in my system. I'm not going to try my suggestion as I prefer to use a preamp to be honest. Also, the current amps are not at full output anyway otherwise they sound overloaded. Backed off as they are they sound better. For an outlay of 38 quid I am going to buy a pair of RCA attenuators by Rothwell to see how I get along. If that fails it'll be a passive preamp.

[Macca]

Martin, I tried a Behringer years ago and it was so bad it was unusable in my system. I'm not going to try my suggestion as I prefer to use a preamp to be honest. Also, the current amps are not at full output anyway otherwise they sound overloaded. Backed off as they are they sound better. For an outlay of 38 quid I am going to buy a pair of RCA attenuators by Rothwell to see how I get along. If that fails it'll be a passive preamp.

Good plan. I had a brace of the Behringers a few years back, used with a Croft pre-amp they sounded diabolical. Some sort of overload issue. Used with a passive pre - perfectly acceptable, although not world-shattering.

[Haselsh1]

Good plan. I had a brace of the Behringers a few years back, used with a Croft pre-amp they sounded diabolical. Some sort of overload issue. Used with a passive pre - perfectly acceptable, although not world-shattering.

No but then I'm guessing they didn't cost 'World shattering' money..?

My current Crown amps sound very coarse and grainy in the upper mid/lower treble but then they are very cheap amplifiers. I have noticed though that if I get close to the KEF's Uni-Q driver the sound appears overloaded and compressed but this is dependant on the source material. On loud guitar and synth 'Ozrics' type material it is over exaggerated and coarse but with very high quality production the sound is pretty good.

I'm going to have to think a bit about this.

[Macca]

Similar Crown amp to yours tested here https://www.audiosciencereview.com/f...-review.10627/

Gets a recommended. Quite a bit of harmonic distortion but not enough to be audible, apparently. I reckon your problem is poor matching with your pre-amp.

[Haselsh1]

Similar Crown amp to yours tested here https://www.audiosciencereview.com/f...-review.10627/

Gets a recommended. Quite a bit of harmonic distortion but not enough to be audible, apparently. I reckon your problem is poor matching with your pre-amp.

I think you're right Martin

[Macca]

Passive here for £44.44 delivered. Cheap way to test the concept. https://www.ebay.co.uk/itm/193061024...&hlpv=1&cond=1