rowemeister said:Hi all.
I have done a mod which many of you will just laugh at 🙁
And its no where near has complex as the tube mod, but I am keeping an open mind.
The LED mod
I will test this fully to see if there is any difference.
Wooow, ----pimp my player----
I know a fellow-DIY'er that put green LED's in his player and told me the bass had improved considerably. He also uses the greem marker on the edges of his cd's. I haven't had the chance to hear the differences, but if you detect any, i'm going to try it too 😀.
Ray.
awpagan said:
Hi Allan,
I managed to fix my scanner bug, and I have the board lay-out for you. It's a bit too big to post here, if you drop me a PM I will send it to you.
Ray.
poynton said:
Hi.
Another day .....had to repair the power supply this morning - somehow the Tx developed a primary short. Luckily I had a New TX to hand so I could repair it.
Worth the wait though !!!!!!!!!
Now using one of the minature tubes ( 6BF7W ).
Really excellent sound - possibly a little lighter on the bass than the E88CC but only a RCH !
B+ is incredible - it does not seem to distort (audibly) until B+ goes down to 3.5v - Correct 3.5v !! then it cuts off anyway ! I will keep it at B+ = 25v - audible performance does not seem to improve above this.
Heater is running a bit bright for my liking and gets HOT. I will try on 5v regulated supply rather than 6.3v AC
Andy
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6h5c said:
Hi Ray,
Do you still have the hiss??
I have been playing with the latest incarnation with interesting results!
Refering to Thorsten's circuit...
I used a probe connected to my amp at various points.
I could only detect significant hiss at the input at the junction of the choke and the DAC output ( where you would expect - no filtering whatsoever).
The interesting part is that after the choke, some hiss, slight buzz - and perfectly acceptable music !
Have I just found the ultimate minimalist mod?? straight off the DAC with a filter - no op amps, tubes etc??
Try it.
Andy
Hi Andy!
Nice results! Especially at this low voltage.
Did you use a current sink for the kathodes, or a resistor?
You really got me going on this!
I went to the dump-store this afternoon, and I picked up some 5672 and 6418 pencil-tubes. They are low-voltage direct-heated penthodes that use 1,25V heater supply! I don't know if they're any good, but one of them has got very nice triode characteristics!
As soon as I have the passive part finished i'm going to try them.
Regards,
Ray.
Nice results! Especially at this low voltage.
Did you use a current sink for the kathodes, or a resistor?
You really got me going on this!
I went to the dump-store this afternoon, and I picked up some 5672 and 6418 pencil-tubes. They are low-voltage direct-heated penthodes that use 1,25V heater supply! I don't know if they're any good, but one of them has got very nice triode characteristics!
As soon as I have the passive part finished i'm going to try them.
Regards,
Ray.
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poynton said:
Yes, it is still there. But it is not audible with music playing. I only noticed it when I turned the volume of my amp to 100%, to see if the tubestage was humming/making noise. But my CD63, which uses the standard opamps + filter also produces the same hiss. So I THINK it is a HF residue caused by the DAC. It was about 22mV in amplitude, and Brent also measured it. Did you check with a scope yet?
poynton said:
Ehm, a shop with lots of junk, where they sell old army stuff and surplus parts, I don't know the exact word in english. They have at least two boxes full of these, they only cost me € 1,00 each! So I bought four of both types.
Ray.
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The connector on my main pcb to the transport pcb is playing up.
Its defo connector as I have changed the ribbon.
Will it be worth wiring this connection out with silver wire?
Or silver wire for just the RF out?
Its defo connector as I have changed the ribbon.
Will it be worth wiring this connection out with silver wire?
Or silver wire for just the RF out?
Hi Brent,
I don't know if silver will add anything there. It's mostly servo signals going though. I'd rather go for a shielded connection, like a piece of shielded ribbon. Maybe a separate coax for HF??
Any big sound-changes detected yet, with the blue LED's?
Ray.
I don't know if silver will add anything there. It's mostly servo signals going though. I'd rather go for a shielded connection, like a piece of shielded ribbon. Maybe a separate coax for HF??
Any big sound-changes detected yet, with the blue LED's?
Ray.
This, for example:
http://www.military-tubes.com/index_en.html
When you have good luck, you find sometimes under the label "sub-micro tubes" 250g tubes for 5 Euro!
I ordered 500gr and got more than 160 tubes:
Many 6021, 6111, 6112 double triodes. And many 5702, 5636 and some other pentodes, and Diodes, Regulators and so on.
Franz
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Hi.
I wish we had places like this in the UK. Maybe we do but I know of none!
Franz - what a bargain. Sadly it's not available now.
Andy
I wish we had places like this in the UK. Maybe we do but I know of none!
Franz - what a bargain. Sadly it's not available now.
Andy
Hi Franz,
Cool site! I love those places.
I'm very glad I have a place like that about half an hour driving from where I live. It's called "BACO". I go there like once in a month to check if they have new things. They have a (dutch) website too: http://www.baco-army-goods.nl/
This is my tube-collection so far. About half of it (and the boxed ones) comes from the dump-store, and the other half is old TV tubes (PL series).
Ray.
Cool site! I love those places.
I'm very glad I have a place like that about half an hour driving from where I live. It's called "BACO". I go there like once in a month to check if they have new things. They have a (dutch) website too: http://www.baco-army-goods.nl/
This is my tube-collection so far. About half of it (and the boxed ones) comes from the dump-store, and the other half is old TV tubes (PL series).
Ray.
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ray
got the pdf with the pcb layout
awesome! thank you very much😀
something to investigate while i'm waiting for the tent clock.
rowemeister
HF signal - Data Signals, how about cat5?
andy
"Have I just found the ultimate minimalist mod?? straight off the DAC with a filter - no op amps, tubes etc??"
Internal dac filter?
now back to work
allan
got the pdf with the pcb layout
awesome! thank you very much😀
something to investigate while i'm waiting for the tent clock.
rowemeister
HF signal - Data Signals, how about cat5?
andy
"Have I just found the ultimate minimalist mod?? straight off the DAC with a filter - no op amps, tubes etc??"
Internal dac filter?
now back to work
allan
rowemeister said:
Cat5(e) is network cable. (e) i think
supposed to be designed for insulated 100Mhz+ data transfer
at the frequency we need should not pickup to much noise
cleaner data transfer?
a couple of posts somewhere in the diy forum were looking at it
don't remember the outcome or where i saw it.
I see if i can find it.
allan
just did search
lots of ref to cat5e
some were using for interconnect cable
will try to narrow it down
rowemeister said:
I was looking for info on i2s data transfer and the cat5 seemed like the easiest idea.
bit more data
http://www.diyaudio.com/forums/showthread.php?s=&postid=166115&highlight=#post166115
jocko's in good form
allan
