vari-mu - which one and diferences?

[Kingston]

If we're talking about the real thing, I'd disagree.  Transparent is not a word I'd use to describe a 670 and it's definitely far from the most transparent.

I meant the compression performance itself is very transparent. You can't tell its there when it's used as intended shaving peaks in vinyl mastering or gently doing the automatic fader ride on spoken word material.

Today it's different because who in their right mind after spending 30 grand wouldn't want to underline the fact they are using a Fairchild 670 and hence slam it to death. "guys we have two more weeks before a 2-grand retube. if you're gonna use it, make it count!"

 

[ruairioflaherty]

I meant the compression performance itself is very transparent. You can't tell its there when it's used as intended shaving peaks in vinyl mastering or gently doing the automatic fader ride on spoken word material.

I think we have different ideas of what transparent is, I'm a mastering guy so I guess my threshold for transparent is a lot higher.  I really like 670s when they are working but even at moderate gain reduction they have quite a strong effect on the audio.  Just a perspective and we all hear things differently.

 

[Kingston]

I think you may be talking about the overall signal path. More than 1% IMD can be a bit grainy and mushy, sure. And those transformers.

I was referring to control voltage shape/speed (as in compression performance) and the way it's working to a very soft knee. In fact the softest knee you can probably get. Very few equals.

Today it should be done with a chipamp or a light weight power amp into good quality vari-mu tubes. It's a bit strange no one jumped on that boat. I know only a few DIY folk who did that.

 

[mikeyB]

I think you may be talking about the overall signal path. More than 1% IMD can be a bit grainy and mushy, sure. And those transformers.

I was referring to control voltage shape/speed (as in compression performance) and the way it's working to a very soft knee. In fact the softest knee you can probably get. Very few equals.

Today it should be done with a chipamp or a light weight power amp into good quality vari-mu tubes. It's a bit strange no one jumped on that boat. I know only a few DIY folk who did that.

Hi Kinston - yeah thats the route to go i reckon with solid sidechain poweramp  and lots of flexibility with filtering!
Would love to try a gyraf 10 - thats ss sidechain. About to repair a manley varimu and intersted to see how that sounds! (yeah - i know thats NOT SS sidechain)

Like the M670 thread! - good on you!
I too got 2 PM670 kits but didn't like the thought of tackling it having seen the problems! Now there may be chance i'll finally do it using your model!
Finally getting round to sorting 3 (expensive!) chiswick clone kits i was left hanging with when it all went sour with the Tat saga!

I'll PM you re the M670 progression - i do pcb layout!

 

[shot]

I've been reading through this topic and got interested in Altec p2p build!
Where can the documentation be found?
I searched through forum and only Drip's and pcb version is mentioned.

 

[geoff004]

I've been reading through this topic and got interested in Altec p2p build!
Where can the documentation be found?
I searched through forum and only Drip's and pcb version is mentioned.

I actually found some good schematics and documentation over on drip's forum.  I think you can find his build manual too which is good for a parts list.