Equipment that used Langevins or Davens

[Phrazemaster]

Not sure where to post this. I still think the new magnetics sub forum should be generic to components.

I’m trying to source a pair of Langevin attenuators for an authentic build: Langevin AT 601 to be precise. It’s a T attenuator 600/600.

I rarely ever see any Langevins come up on eBay. So I thought maybe if I could find some old equipmen5 that used them that might be the way to go.

How do I find out what old equipment used these?

I could also use a Daven T. Although these are more numerous it’s still hard to find exact parts. I would look for a T-257-g or a T-520-g.

Thx for your insights.

Mike

I rarely

 

[emrr]

You would have to study the manuals of all old equipments to find that particular answer.

It would help if you would spell out the specs of the ones you seek, and tell us what you will be doing with them.  Then we could maybe help you avoid 'literalism' if it's unnecessary, or if it's necessary, tell us why. 

 

[Phrazemaster]

You would have to study the manuals of all old equipments to find that particular answer.

It would help if you would spell out the specs of the ones you seek, and tell us what you will be doing with them.  Then we could maybe help you avoid 'literalism' if it's unnecessary, or if it's necessary, tell us why.

Thanks Doug, I was afraid of that.

I’m looking for the exact parts used in the 176 compressor, so close enough is not what I’m after. I just like authenticity in my builds when possible.

So the specs for one are: unbalanced ladder 600/600, 40db attenuation over 20 steps, no infinity cutoff in last step, detents, and bushing installation.

The other is the same specs but in a bridged T.

I know I can use modern equivalents but I’m really after the exact parts if poss.

Thanks much

Mike

 

[emrr]

Hmm, Daven LA-353-G shown on that schemo for both. 

There are 176, 176-T (1) and 176-TT (2) variations according to the catalog.  Sounds like you want the additional +6 on the output side.

It might matter to me personally if I were going 'full counterfeit', even then there are variations.  If they were like a lot of companies, they probably used multiple things.  They used multiple transformer types from multiple companies too. 

So.....temper that with the question of do you have original transformers?

I know I have RMX-601 and RMXD-601, probably a later name change, and D probably the version with a cue position. 

 

[Phrazemaster]

Hmm, Daven LA-353-G shown on that schemo for both. 

There are 176, 176-T (1) and 176-TT (2) variations according to the catalog.  Sounds like you want the additional +6 on the output side.

It might matter to me personally if I were going 'full counterfeit', even then there are variations.  If they were like a lot of companies, they probably used multiple things.  They used multiple transformer types from multiple companies too. 

So.....temper that with the question of do you have original transformers?

I know I have RMX-601 and RMXD-601, probably a later name change, and D probably the version with a cue position.

All true - I’ve heard of variations on a lot of the components. I do have orig output xformers.

The RMX601s are almost exactly right, but they have an infinity cutoff on the last step. Original did not; 20th step was 40th dB attenuation.

From the manual it appears an AT 601 was the specified replacement. I bet an RAT601 would also work but I’m not sure.

Doug you have an encyclopedic knowledge of this stuff and I’m grateful for your contributions.

 

[jslstudio]

Not sure where to post this. I still think the new magnetics sub forum should be generic to components.

I’m trying to source a pair of Langevin attenuators for an authentic build: Langevin AT 601 to be precise. It’s a T attenuator 600/600.

I rarely ever see any Langevins come up on eBay. So I thought maybe if I could find some old equipmen5 that used them that might be the way to go.

How do I find out what old equipment used these?

I could also use a Daven T. Although these are more numerous it’s still hard to find exact parts. I would look for a T-257-g or a T-520-g.

Thx for your insights.

Mike

I rarely

In the manual it says use AT 601 If you desire 6 db more on the output. Many old 600/600 stepped or not stepped will work. Also as an option the 176 listed NON stepped as an option also...
Did you ever finish your build?
John

 

[Phrazemaster]

Hi John,

I had Daven (now Shallco) custom-remake the Daven part for me.

No, haven't done the build yet sadly. Life got in the way and I'm now in England - but with all the parts sitting silently waiting for my attention.

By the way I used the special GM blue that you recommended, and WOW did they come out beautifully!!!

I'll post back when I get the build done, but probably sooner when I run into questions.

Thanks,

Mike

 

[Phrazemaster]

Hi John,

I had Daven custom-remake the Dave part for me.

No, haven't done the build yet sadly. Life got in the way and I'm now in England - but with all the parts sitting silently waiting for my attention.

By the way I used the special GM blue that you recommended, and WOW did they come out beautifully!!!

I'll post back when I get the build done, but probably sooner when I run into questions.

Thanks,

Mike

Just for general reference, when I contacted Shallco to have the Daven part made, this was the data:



So I opted for the T-257-G, which Shallco told me was replaced with the T-322-G.

Hopefully this part number info will be helpful to someone.

Thanks,

Mike