Christmas offering.... Fairchild Valve EQ ..... ez627

[Slenderchap]

https://www.youtube.com/watch?v=y4kYXYMtX44

 

[Beau]

Build this kit a few weeks ago. Waiting for the last tube to arrive as I accidentally ordered a 6e5GT which I thought was the same as a 6e5C but the pin-out is different after all. Should have a 6e5 coming in early next week tho

Can anyone that has build these kits shed some light on wether they need any calibration? The circuit does have a trim pot but I'm unaware of its purpose.

 

[Beau]

Got the last tube in today and assembled the unit in it's chassis. One small thing that I hope here someone can tell me if thats fine or  problematic; I measure 241vdc at testpoint 10. Any reason for concern or fine as is?

If anyone else has some hints as how to check the unit for proper operation, happy to hear! Leaving it on for some hours now to see if no smoke arrises and then will test it later this week with some audio passing trough

 

[Beau]

I also inquired with Colin from AML on these subjects, I'll share it here in case people run into the same questions;

You can set the HV voltage with R41 (it is SOT ... select on test)... personally I would not bother... it is within 10% anyway... and it will change with different valves.

The only adjustment we do is the trimmer which sets the sensitivity of the magic eye tube.

 

[Majestic12]

I've just finished my ez627 kit

 

[rock soderstrom]

Wow, ultra clean built! I like the magic eye, of course!

 

[echoplex]

I love the magic eye too! Hope to see this more on DIY kits and projects

is this kit/project still available? PCBs somewhere?

 

[Majestic12]

is this kit/project still available? PCBs somewhere?

Sure, you can buy a kit at the Audio Maintenance Limited online store.

 

[TillM]

Markus I’m always impressed from your work desk. 
Nice to see this equalizer.

PS: your package arrived 

 

[jensenmann]

Congrats, Markus! So how does it sound?

 

[Majestic12]

Congrats, Markus! So how does it sound?

It is superb on kick and bass. Much tighter than a Pultec and it allows you to distort the frequency bands you are going to boost.

 

[petermontg]

Sure, you can buy a kit at the Audio Maintenance Limited online store.

. 

Hi majestic

Where do you pick up your Mu shielding.

Best
Peter

 

[Majestic12]

. 

Hi majestic

Where do you pick up your Mu shielding.

Best
Peter

I don't understand. Which Mu shielding?
Do you mean the shielding box around the power supply section ? It's part of the kit from AML.

 

[SKJGProject]

Where do you guys get the valves for this eq?

 

[Beeswax]

It is superb on kick and bass. Much tighter than a Pultec and it allows you to distort the frequency bands you are going to boost.

You touched on one of my questions. Can you comment further on how it compares/contrasts to a Pultec? Wondering which of these projects to build and given the supply chain issues I'm inclined to go with a pre-prepare kit.

 

[Beeswax]

I´ve built this unit in one very pleasant evening and have to say, this is by far the best kit I have ever seen. Also, it was one of the best and most satisfying evenings I´ve ever had cause it culminated in adding a very nice unit to my studio.

Everything is hasslefree, superbly organized and very thought through designed.

It holds ups to the highest standards.

Also, it sounds incredible. I spent a lot on nice tubes. Might be experimenting with different Input and Output Irons though, there is plenty of space left in the case, even though it will mess up the neat inner parts.

I'm a little in the dark on tubes. Can you recommend the ones you like for this build?

 

[soapy_goat]

I'm a little in the dark on tubes. Can you recommend the ones you like for this build?

Hello Beeswax,

hopefully, this is still relevant at least to future readers...

I used the cheapest tubes I could source for V1, V2, V5. I spent about 5$ each and turned out to be NOS assorted GE, RCA, military types. that's cool I guess according to the "hifi scholars"? I guess not a huge demand for those types.

V3 and V4 (the 6SN7s) I spent a bit more. I used Tung-Sol Russian reissues (about 40$ each). My thought was... NOS "nice" tubes can still be found down the line if I hear something terrible! I haven't heard anything terrible! This circuit will probably sound awesome with almost any type of new or old NOS tube in it. My non-electrical engineer brain thought the 4 6SN7s (total for my stereo pair, I have 2 627s now...) should be similar to each other, as they are probably most characterizing the audio. if I wanted 4 of the same """" hifi scholarly recommended nice"""" NOS Sylvania, RCA, KEN-RAD... oof that's nearly the cost of the kit!

For the magic eye, I recommend checking ebay for a NOS Toyo 6E5, they're nice and bright! Buy it from the guy in NY!

I am here to make rock n roll! No more time for a tube tangent!

 

[Beeswax]

Hello Beeswax,

hopefully, this is still relevant at least to future readers...

I used the cheapest tubes I could source for V1, V2, V5. I spent about 5$ each and turned out to be NOS assorted GE, RCA, military types. that's cool I guess according to the "hifi scholars"? I guess not a huge demand for those types.

V3 and V4 (the 6SN7s) I spent a bit more. I used Tung-Sol Russian reissues (about 40$ each). My thought was... NOS "nice" tubes can still be found down the line if I hear something terrible! I haven't heard anything terrible! This circuit will probably sound awesome with almost any type of new or old NOS tube in it. My non-electrical engineer brain thought the 4 6SN7s (total for my stereo pair, I have 2 627s now...) should be similar to each other, as they are probably most characterizing the audio. if I wanted 4 of the same """" hifi scholarly recommended nice"""" NOS Sylvania, RCA, KEN-RAD... oof that's nearly the cost of the kit!

For the magic eye, I recommend checking ebay for a NOS Toyo 6E5, they're nice and bright! Buy it from the guy in NY!

I am here to make rock n roll! No more time for a tube tangent!

Thanks for the details. I'll build it eventually.

 

[axcell]

Hi, I completed a pair of ez627 recently and I'm currently at the assembly step. I decided to try and fire it up on one of my units to make sure everything is alright, but without having the pots/attenuators plugged in, which resulted in magic smoke...
I was wondering if the cause could have surely been the lack of plugged pots/attenuators, or if it could have been something else?

 

[Undos]

Hi, I completed a pair of ez627 recently and I'm currently at the assembly step. I decided to try and fire it up on one of my units to make sure everything is alright, but without having the pots/attenuators plugged in, which resulted in magic smoke...
I was wondering if the cause could have surely been the lack of plugged pots/attenuators, or if it could have been something else?

Not much in there. Do you know where the smoke came from? I’m not familiar with the unit but have you visually double checked the orientation of the components ? Be careful because of the high voltage inside the device (even unplugged for several minutes there could remain lethal voltage) better unload the caps.