Mic pre with switchable doa's

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pucho812

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Discuss pro's and cons to a 312 style  mic pre that has a switch allowing the operator to switch between 2 different doa's so that you are using one of the two for your mic. Worth it?
 
I really don't think a DOA has THAT much influence on the freq response. I have six 312's with 5 new 2520's and 1 Studio Systems Division(ancient) 2520. No real big difference in how they sound...other than the new ones seem to have a bit more output.  :eek:

I'm thinking that if it were something that really had an effect on the sound, like for example; a transformer, then it probably would've been done by now. And, imo, there's far more important things to consider when tracking a 'song.

The less things to distract from the important stuff....the better.
 
thw switching transformer thing has been done. I as as I saw a mic pre at namm today that had switchable output transformers and switchable doa's. I didn't get into much of the doa part. When I refer to 312 style I mean single doa with in and out transformers. So the DOA switching would go from like a 2520  and 990, pick one to use. I am not convinced it's that much of a wow factor other then to the sluts. 
 
pucho812 said:
So the DOA switching would go from like a 2520  and 990, pick one to use.

That's what i was understanding from your post. Might be a market for it......just make sure it has nice knobs and it'll sell.  :)

Maybe something that's switchable between two different circuits/topologies...say DOA and Germanium? Something that would make a significant difference to the sound...but still remain practical and usable.
 
pucho812 said:
thw switching transformer thing has been done. I as as I saw a mic pre at namm today that had switchable output transformers and switchable doa's. I didn't get into much of the doa part. When I refer to 312 style I mean single doa with in and out transformers. So the DOA switching would go from like a 2520  and 990, pick one to use. I am not convinced it's that much of a wow factor other then to the sluts.

the matter is that only using trasparent trasformers you can hear important differences between two different DOA's. The 312 pre very often has not so trasparent trasformers. Moreover, the pre's circuit is important too, 312 is not so trasparent design. Something like M1 is good. 
 
Well the same unit also had switchable output transformers like you would find on shadow hills units. If you ask me all that switching is pointless. I figure instead of options just give people something that sounds good.

 
pucho812 said:
Well the same unit also had switchable output transformers like you would find on shadow hills units. If you ask me all that switching is pointless. I figure instead of options just give people something that sounds good.
In my opinion the out options should be 4:

1.  all steel trasformer
2.  50% nickel transformer
3.  80% nickel transformer
4.  transformerless.
 
keefaz said:
Maybe switchable loads could be cool, I mean switchable resistors at doa output to load it more or less hard ?

good,

so adding a pot should be better
 
pucho812 said:
Well the same unit also had switchable output transformers...

At that point I'd rather just have two channels of preamp. Seems a waste to have almost an entire second channel worth of components sitting dormant in the box at all times.
 
adeptusmajor said:
pucho812 said:
Well the same unit also had switchable output transformers...

At that point I'd rather just have two channels of preamp. Seems a waste to have almost an entire second channel worth of components sitting dormant in the box at all times.

ok, yes it is right, but two different normal pres do not give the same command on sound.

The shadow hill pres infact cost a bit more than the others for this reason, in the sense that the major cost of the 2nd transformer inside it is accepted for the greater ability that this pres offer to customers to handle sound. 







 
The engineers at Abbey Road and Trident didn't need elaborate, endless features in order to make excellent sounding records. I don't know why it would be required now.

http://www.youtube.com/watch?v=SYXAq-cnXRw
 
Decadent usage , and I'm guessing not worth the effort  , but wonder if you'd hear
the charactor by putting two in parallel ?
 
Could be cool. But if you have multiple sets of Opamps and transformers, one begs the question...why not build more pres?

For a commercial type product it would be really cool to have 2 sonic flavors in one box, Though 2 different discrete opamps might not give very noticeable difference, a dirty discrete opamp (think early quad 8) and maybe a monolithic super clean opamp would. Just keep good in/out iron, like say jensen and i'm sure people would love it.
 
desol said:
The engineers at Abbey Road and Trident didn't need elaborate, endless features in order to make excellent sounding records. I don't know why it would be required now.

http://www.youtube.com/watch?v=SYXAq-cnXRw

OK, I agree with you,  is not needed a multiple out trasformers preamp to make nice sound, there are  many good pres with only one out trasformer in the market, and i think that a recording studio should have mainly these ones  but it do not exclude to have in the market preamps with switchable out trasformers, or DOAs, for who want have a multiconfigurable pre.
 
desol said:
Gotta keep the economy going somehow, right?  ???

yes, it is, marketing is important,  ;D but i think that this type of pre has its function.  8)

I personally just two days ago I have thought to make a preamp with the holes for 3 out trasformers.
I make some trasparent DOAs so I could offer a preamp with the sound of its trasformers. 
 
Years ago I made a mic pre that had switchable 2520 and 990 style doa's with one set of tranformers. It had dual rev log pot and couple of relays for switching. It works fine but it's true that the difference in sound is actually pretty small. I rarely use the 990 because the 2520 has little more appropriate color with the api type transformers that I used.
 
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