Hello folks, to add to my reputation of not knowing what I'm talking about, here is another dumb question.
I think I already know the answer to this one but here goes anyway just in case.
I have a pair of Cambridge Audio P500 Power-Amps driving my stereo speakers. They each have a pair of inputs. I also have a Yamaha DSP E800 add-on AV processor that feeds line level signal to the Pre-amp for the stereo speakers and has it's own built in amplifiers for the centre and rear speakers.
If I connect the Yamaha directly to the inputs of the power-amps I get very little sound. Is there any way of fitting a gain control to one set of the power-amps inputs to increase the input signal? I'm guessing this would require incorporating a signal booster of some description (pre-amp).
The reason for wanting to do this is to make operation simpler for the family. At present they have to turn the whole stereo on and wind the volume up to half to balance the levels so I'm guessing the output from the Yamaha is pretty low level. If I could boost the signal to the power amps to a sufficient level to be able to bypass the pre-amp then it's one less thing to worry about and greatly reduces the risk of accidents (such as leaving the volume wound up to half and switching the input over to CD etc...).
Thanks for any help, if I don't ask I might miss out on a simple solution.
Cheers.
I think I already know the answer to this one but here goes anyway just in case.
I have a pair of Cambridge Audio P500 Power-Amps driving my stereo speakers. They each have a pair of inputs. I also have a Yamaha DSP E800 add-on AV processor that feeds line level signal to the Pre-amp for the stereo speakers and has it's own built in amplifiers for the centre and rear speakers.
If I connect the Yamaha directly to the inputs of the power-amps I get very little sound. Is there any way of fitting a gain control to one set of the power-amps inputs to increase the input signal? I'm guessing this would require incorporating a signal booster of some description (pre-amp).
The reason for wanting to do this is to make operation simpler for the family. At present they have to turn the whole stereo on and wind the volume up to half to balance the levels so I'm guessing the output from the Yamaha is pretty low level. If I could boost the signal to the power amps to a sufficient level to be able to bypass the pre-amp then it's one less thing to worry about and greatly reduces the risk of accidents (such as leaving the volume wound up to half and switching the input over to CD etc...).
Thanks for any help, if I don't ask I might miss out on a simple solution.
Cheers.
Autotat. If there is not enough signal from the Yammy you would need an additional active pre-amp. This would then be your Yammy gain control. The P500 has two sets of inputs and you can still have the output from the main pre-amp going into the P500s.
I assume that there are no other line-outs that have more gain?
Rob.
I assume that there are no other line-outs that have more gain?
Rob.
Hi Rob,
Thanks or the speedy reply, I thought that would be the case. There are only one set of line-outs for each signal path.
I'll do a search to see if I can find a small dedicated pre-amp to do the job.
Many thanks for taking time to reply.
Simon.
Thanks or the speedy reply, I thought that would be the case. There are only one set of line-outs for each signal path.
I'll do a search to see if I can find a small dedicated pre-amp to do the job.
Many thanks for taking time to reply.
Simon.
I already have that for main stereo duties.
I was hoping to find some way of plumbing the AV amp directly into the power-amps. I have seen small phono stage pre-amps on amazon that would discretely hide behind the Hi-Fi so if I could perhaps look at building something similar. The AV amp has a power socket built in as with many japanese products so if I plug it into that it will automatically switch on when I turn the AV amp on.
I was hoping to find some way of plumbing the AV amp directly into the power-amps. I have seen small phono stage pre-amps on amazon that would discretely hide behind the Hi-Fi so if I could perhaps look at building something similar. The AV amp has a power socket built in as with many japanese products so if I plug it into that it will automatically switch on when I turn the AV amp on.
OK, I wasn't aware that you were intending a DIY option. I assumed that as you had a C500 that another would match.
I built a SOAP (Simple Op-Amp Pre) details are on this forum, however it is unlikely that there are any PCBs still available.
http://www.diyaudio.com/forums/chip-amps/122639-soap-mkiii-simple-opamp-pre-onboard-psu.html
You could use one of these.
http://www.ebay.com/itm/STEREO-NE55..._Audio_Amplifiers_Preamps&hash=item23099c3ce4
I built a SOAP (Simple Op-Amp Pre) details are on this forum, however it is unlikely that there are any PCBs still available.
http://www.diyaudio.com/forums/chip-amps/122639-soap-mkiii-simple-opamp-pre-onboard-psu.html
You could use one of these.
http://www.ebay.com/itm/STEREO-NE55..._Audio_Amplifiers_Preamps&hash=item23099c3ce4
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Ah, sorry, you meant have a second C500 purely for the Yamaha's signal. I don't have the space for another full size box and the wife wouldn't go with it either.
I'm looking for something small that can live out of sight behind the rack. I have seen numerous Phono Pre-Amps on amazon that re bot the right sie but they have no gain control and I don't know if a phono amp is even suitable?
I don't mind trying DIY if that's the only way to get what I'm after.
I'm looking for something small that can live out of sight behind the rack. I have seen numerous Phono Pre-Amps on amazon that re bot the right sie but they have no gain control and I don't know if a phono amp is even suitable?
I don't mind trying DIY if that's the only way to get what I'm after.
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Be careful. A Phono Pre-Amp is normally the term for a step-up stage for a turntable and is at a fixed level, hence no volume pot.
Other than a lack of volume pot and so a fixed output, are there any other differences to a normal pre-amp?
Well as they are normally used with the very low output from a TT cartridge the gain may well be too much and you cannot turn it down. You will probably have your current problem in reverse.
I wonder if I could add a couple of pots to a phono amp? They are around the £30 mark on Amazon so might be worth a punt.
Hi,
A phono amp won't work, it has the RIAA response curve. A mic amp might.
AFAICT your setting for the levels of the centre and rears is too high and
overall main level too low, set up properly you shouldn't need a preamp.
Make sure main level is Normal, not -10dB.
rgds, sreten.
A phono amp won't work, it has the RIAA response curve. A mic amp might.
AFAICT your setting for the levels of the centre and rears is too high and
overall main level too low, set up properly you shouldn't need a preamp.
Make sure main level is Normal, not -10dB.
rgds, sreten.
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Sreten. The manual says that when connecting a 2 channel amp to the Main Out phonos, set the volume control of the external amplifier to -16 to -18dB.
Autotat. I am 30 mins from Basingstoke, so an hour from Andover?
Rob.
Autotat. I am 30 mins from Basingstoke, so an hour from Andover?
Rob.
I didn't think a phono amp would be any good.
The AV processor doesn't have any adjustment for the line level outputs to the stereo amp. The surround speakers where all set to there lowest values. The manual simply instructs you to adjust the volume control on the stereo amp whilst using the built in test sound until the volumes from all five speakers match. Thinking about it, my volume control is, as stated previously, set to the half way mark which is blumin high for a line level input on that amp. Maybe the Yamaha has been carrying a fault all this time?
Puffin, I'm about ten minutes west of Andover, so not too far in the grand scheme of things.
The AV processor doesn't have any adjustment for the line level outputs to the stereo amp. The surround speakers where all set to there lowest values. The manual simply instructs you to adjust the volume control on the stereo amp whilst using the built in test sound until the volumes from all five speakers match. Thinking about it, my volume control is, as stated previously, set to the half way mark which is blumin high for a line level input on that amp. Maybe the Yamaha has been carrying a fault all this time?
Puffin, I'm about ten minutes west of Andover, so not too far in the grand scheme of things.
The AV processor doesn't have any adjustment for the line level outputs to the stereo amp.
Hi,
It does. Normal (default) and -10dB. Make sure its not set at -10dB.
rgds, sreten.
Hi,
Your power amplifiers do not have 2 sets of inputs. They have 1
input and a daisy chain output for paralleling amplifiers for passive
bi or tri amping or driving a subwoofer line input. A||C, B||D.
You can't connect the Yahama directly to the power amps as well
as your Cambridge C500 pre-amp, it has to be one or the other.
rgds, sreten.
Your power amplifiers do not have 2 sets of inputs. They have 1
input and a daisy chain output for paralleling amplifiers for passive
bi or tri amping or driving a subwoofer line input. A||C, B||D.
You can't connect the Yahama directly to the power amps as well
as your Cambridge C500 pre-amp, it has to be one or the other.
rgds, sreten.
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You can't connect the Yahama directly to the power amps as well
as your Cambridge C500 pre-amp, it has to be one or the other.
Didn't think he was trying to do that, was he?
My suggestion was that he fed the Yamaha into another gain stage. Both this and the C500 could be connected to the P500s as long as they were not both on together. He wants to avoid having to put the C500 on for AV duties to the main speakers.
Puffin, I'm about ten minutes west of Andover, so not too far in the grand scheme of things.
I asked where you were because I have made friends with several members of this and other fora and it's good to have another pair of eyes/hands/support if you are doing DIY. So, if you go the DIY route to solve your problem I might be able to help, if you needed it.
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