Valve phonostage build
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- Shed dweller
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#16 Re: Valve phonostage build
Looks to be the same cct as the WD phono2/3 and the MJ one. Should sound good. Responds well to a good PSU and CCS on the front end.
Only the Sith deal in absolutes.
- pre65
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#18 Re: Valve phonostage build
The only thing necessary for the triumph of evil is for good men to do nothing.
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
#20 Re: Valve phonostage build
This might be a daft question but forgive my naivety. I am new to this.
Is using a square wave the best way to judge and alter the RIAA equalisation? I also hope that makes sense
Is using a square wave the best way to judge and alter the RIAA equalisation? I also hope that makes sense
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#21 Re: Valve phonostage build
Nick will know but I would have thought a better way is to use a reverse RIAA board/test setup to check the response...
https://hagerman-audio-labs.myshopify.c ... iaa-filter
https://hagerman-audio-labs.myshopify.c ... iaa-filter
Only the Sith deal in absolutes.
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#22 Re: Valve phonostage build
Seems you can use a Square Wave in conjunction with a Reverse RIAA stage
http://hifisonix.com/wordpress/wp-conte ... e-RIAA.pdf
Page 6 and 7
http://hifisonix.com/wordpress/wp-conte ... e-RIAA.pdf
Page 6 and 7
Only the Sith deal in absolutes.
#23 Re: Valve phonostage build
Yes, a square wave and inverse RIAA is a good way, but will only get you so close. Also remember you need to limit the rise time of the input square wave else the inverse riaa will try and turn them into very very large spikes that will distract you.
After that a frequency and phase sweep with the inverse riaa is the next step.
After that a frequency and phase sweep with the inverse riaa is the next step.
Whenever an honest man discovers that he's mistaken, he will either cease to be mistaken or he will cease to be honest.
#24 Re: Valve phonostage build
Hi guys
A little late in reply but ended up haven't to make a few modifications to get the sound where I wanted it. The phonostage is in a case and up and running. Sounding very acceptable but with a little bit of noise from the transformer. I've had a JFET input fitted as I just couldn't find an affordable SUT or HA that I liked.
Further mods to be done are to remove the Transformer from the case as I'm getting a mechanical buzz and some noise and then on to the RIAA.
The Square wave is ok, a little rise at the right of the wave, which to my ears is boosting the bass a fair bit. Obviously, it's going to need a bit more fettling.
The iRIAA kit looks interesting, I'll have a look at that.
Thanks for the responses and advice. It's appreciated.
A little late in reply but ended up haven't to make a few modifications to get the sound where I wanted it. The phonostage is in a case and up and running. Sounding very acceptable but with a little bit of noise from the transformer. I've had a JFET input fitted as I just couldn't find an affordable SUT or HA that I liked.
Further mods to be done are to remove the Transformer from the case as I'm getting a mechanical buzz and some noise and then on to the RIAA.
The Square wave is ok, a little rise at the right of the wave, which to my ears is boosting the bass a fair bit. Obviously, it's going to need a bit more fettling.
The iRIAA kit looks interesting, I'll have a look at that.
Thanks for the responses and advice. It's appreciated.
- izzy wizzy
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