rowemeister said:
AndrewT said:
Hi.
The RA advert is really 'snake oil' to solve a proble which is not there !!!
How many modern amps/pre-amps have an Aux / CD input with a sensitivity of 150mV ?? Even my long-departed Quad33 had adjustable sensitivity.
I agree entirely with AndrewT.
If there is an input/output mismatch, you will never get good sound.
Andy
Edit :- I use an Alps Blue to control the volume of my system.
OK for the moment but will probably replace when funds permit with a stepped attenuator. Rebuilding the Garage/workshop takes priority.
Re: cd6000 not so good anymore
Hi.
I am sure nobody was deliberately ignoring your pleas for help. I go away for a day and there are so many new posts, it is easy to overlook one.
I have repaired a couple of CD6000s. The HF board under the CDM causes a lot of problems - chip failure.
There is no way to adjust the laser but as you have a CD67, you could swap over the mechs to see if the situation improves (obviously not the HF boards) Also check the HF connector for a good contact - swap ends.
EDIT :- Also clean all the grease off the rails of the CDM. It sometimes goes a little hard and 'sticky' preventing free movement of the mech. Do not regrease.
Andy
Luke said:
Hi.
I am sure nobody was deliberately ignoring your pleas for help. I go away for a day and there are so many new posts, it is easy to overlook one.
I have repaired a couple of CD6000s. The HF board under the CDM causes a lot of problems - chip failure.
There is no way to adjust the laser but as you have a CD67, you could swap over the mechs to see if the situation improves (obviously not the HF boards) Also check the HF connector for a good contact - swap ends.
EDIT :- Also clean all the grease off the rails of the CDM. It sometimes goes a little hard and 'sticky' preventing free movement of the mech. Do not regrease.
Andy
1) My Marantz KI amp is 150mV (my nad at work is 165mV)
2) I do have better sound with the attenuator fitted. Much more dynamic and open with no loss from the sound I had previous (if it did it would be removed)
3) I am also experimenting with the correct values to use (lowest res value without affecting the cd output)
4) Try it!
Brent
2) I do have better sound with the attenuator fitted. Much more dynamic and open with no loss from the sound I had previous (if it did it would be removed)
3) I am also experimenting with the correct values to use (lowest res value without affecting the cd output)
4) Try it!
Brent
Will said:
Hi Will,
No I have not tried one, yet. I have often heard it's one of the best ways to go, so I am curious, but put off by the cost.
AndrewT said:
Hi Andrew,
Yes, I'm aware that you need a buffer, which is virtually a preamp anyway, just with a little gain! It's still an extra stage to pass the signal through. I do not use loads of gain, but I also need the preamp/gain functionality for at least one other input (soundcard).
I believe it stands for Transformer Volume Control, but I could be mistaken! I think the advantage is that it takes care of impedances without introducing additional stages ie. it gives the best of "both" worlds.
Simon
SimontY said:
Hi Simon,
It's not that expensive if you purchase from here:
http://www.promitheusaudio.com/tvc.htm
Trust me, it's one of the things you won't regret. I have 1 and it is a revelation. This TVC has killed many so called hi-end preamps.
Hi Andrew,
Yes it's short for Transformer Volume Control. Basically it minimises losses in energy unlike resistive based volume control. Reduction in voltage gains are converted to current, so even though at low volumes, there is still a considerable amount of body in the music - instead of being thin.
cheers..
Will said:
Will,
Thanks for the link, it looks like a product born out of a love of music. I don't really want a whole product though, I'd like to make my own "preamp". I will be looking into a TVC at some point down the road. I don't need any more convincing
Back to the topic at hand, isn't it interesting that Audiocom's top CD63KI mods package comes with output transformers??
SimontY said:
Will,
Thanks for the link, it looks like a product born out of a love of music. I don't really want a whole product though, I'd like to make my own "preamp". I will be looking into a TVC at some point down the road. I don't need any more convincing
Back to the topic at hand, isn't it interesting that Audiocom's top CD63KI mods package comes with output transformers??
I need convincing.
transformers can be wound fairly tolorance.
specially made for specific tolarances to match certain impedances at very high prices.
change the input(source) or output(amp)
and the transformer is just a hunk of iron.
allan
Hi Rowe,
Source impedance is one of the main factors in screwing up the carefully selected filters built into most amplifiers.
Similarly, unbuffered volume controls also screw up the impedance matches needed for those input filters, but even worse than a high source resistance.
Can I suggest you try just the Lpad and tell us which suits your system/ears.
I am surprised you came to this conclusion.
Source impedance is one of the main factors in screwing up the carefully selected filters built into most amplifiers.
Similarly, unbuffered volume controls also screw up the impedance matches needed for those input filters, but even worse than a high source resistance.
Can I suggest you try just the Lpad and tell us which suits your system/ears.
awpagan said:
Actually, I might never get to try this, as I'm going to be going a bit active soon and I don't think a TVC fits into these plans very neatly.
Allan, have you heard a TVC?
poynton said:
Hi Andy, it's old. They called it the Tenzing mod iirc, advertised on Ebay. It looked like it might sound very good, almost half as good as mine even
Simon
A while back I mentioned I was in discussions with a bloke and we were designing a low noise voltage regulator.
Well I have a batch here to test out and can conclude they are sonically better than the audiocom super reg, this was heard by only swapping the main 5V reg in a standard CD63 with both regs.
To be honest they should be better as we designed them to be, using lower noise components.
The chip cap at the bottom of the reg (next to the voltage ref component) is 10uF.
Rowegulators LOL
I'll post the specs soon. Just a few details I need to check up on.
Brent
Well I have a batch here to test out and can conclude they are sonically better than the audiocom super reg, this was heard by only swapping the main 5V reg in a standard CD63 with both regs.
To be honest they should be better as we designed them to be, using lower noise components.
The chip cap at the bottom of the reg (next to the voltage ref component) is 10uF.
Rowegulators LOL
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I'll post the specs soon. Just a few details I need to check up on.
Brent
poynton said:
They (to start with) are for doing our upgrade mods, but yes retailing them is a very big posibility. They are all RoHS too.
The pcb is designed to be a swap for the standard regs and also bolt to an heatsink. On a good heatsink the FET is capable of 8 amps.
I also have the negative version.
Brent
SimontY said:
Well, first of all, thank goodness I haven't got limp, lifeless sound! But no, I don't like it. My player goes through a selector switch and a stepped attenuator, then straight on to the power amp. So I have a few contacts and two resistors in the signalpath, and no limpness at all. If it's better with a preamp, which means more electronics in the pathway (so that's contradictive), there must be something wrong with the way the player matches with the amp. Because less stuff most of the times sounds better. Did you try a better/different interconnect? I noticed the previous one I had was rather thin in the low-end, so cables can make a lot of difference.
Ray
avr300 said:
Glenn2 said:
Thanks guys. C5 and C6 are supposed to be inductors, but I was too lazy to draw a shape, so I used electrolytics with the same outline
.And yes, i'm going to make some PCB's myself, but I don't know how much. If there's enough interest maybe a real batch can be made?
Ray
6h5c said:
Happy to hear it Ray! I didn't think for a moment you'd suffer much inadequacy in your sound
My experience gave me mixed feelings and I wouldn't say I'd never go back and try things at least once more before closing the door on such an idea. The sound I got wasn't gutsy enough, it didn't have the dynamic grip and vigour I was after. It was, however, very fluid and detailed, with very low grain. The quality getting better yet worse was very obvious in adding a preamp to the signal path. The next step is to reduce the impact of this as much as possible (low gain, good op-amp, good wiring, single stage etc.)
My interconnect was the Kimber Crystal Cu, an expensive wire.
My power amp was and is DIY using the National LM3886 non inverted with a gain of 34.