Cinemags

[analag]

I find the Cinemag line of transformers to be of good quality and reasonable cost, so much so that I designed this tube pre around two of their offering. CMMI-5C for input and CM9589 for output.
Gain is fixed but can altered by making R13 adjustable e.g. as in a potentiometer.

Analag

 

[rafafredd]

WOW. Looks amazing. A tube opamp!

 

[Bauman]

I'm in love with Cinemag transformers... good price and amazing sound quality and finishing....

cheers!
FAbio

 

[soundguy]

and a small family run business worthy of doing business with. Made in america too. Dont understand why anyone buys jensen, many jensen transformers are cinemag designs in the first place and jensens QC is less than impressive IMO.

dave

 

[SSLtech]

[quote author="soundguy"]Dont understand why anyone buys jensen[/quote]

and they drink gas like crazy...

Keef

 

[FredForssell]

Are you sure about that output stage topology?

 

[rafafredd]

Yeah... Wouldn´t a regular White cathode follower be better?

 

[AMZ-FX]

Were the Cinemag prices previously online? They don't seem to be available now (or I'm blind, which is possible) :grin:

regards, Jack

 

[NewYorkDave]

The open-loop gain is very low. The bottom triode in the output stage is just acting as a glorified cathode resistor. The same tubes could be rearranged into two cascaded stages with a White cathode follower for much more gain and output drive capability. But that's theory--how does it sound?

 

[analag]

Fred I have been a White Cathode Follower (push pull) user for many years until I tried this design, the beauty is in the PSU grunge nulling capability. I can say it gives a blacker background, a more lifelike feeling.
BTW I have two of these cathode followers in my JFET/tube input transformerless mic pre, one per phase. Both lower tube grids tied together and fed by the same nulling network.

Dave you are correct...theory and sound don't correlate well at all. It has enough gain for my mics, my needs if it didn't I would have given it more gain without the need to cascade stages.

I wouldn't want to waste the forum users time with mediocre sounding circuits.

Analag

 

[edanderson]

jack-

i've not seen cinemag prices online in the past 3 years that i've been buying from them. also, they have some designs that aren't listed on the website, but that they will happily sell, so it is worth contacting them with your needs. they have recently updated their site with a few more designs which is most welcome.

ed

 

[Dan Kennedy]

Just out of a sort of vacuum state denseness, what is R18 doing?

 

[analag]

R17, R18 is used to set the null signal level. In some cases U4 is amplifying enough to flip the phase of the PSU noise appearing at C4, what I want to do is null it as much as possible. So level setting is essential.

Analag

 

[nacho459]

I've never heard the Cinimags before, but It looks like they used to have something to do with Altec? Do you just order directly from them?

 

[analag]

Just send an email regarding the transformer you are interested in and they will send you pricing and shipping info...if you choose to buy they will send you a link to the paypal invoice...pay it and you're all set. Email response is prompt from my experience with them. Had no need to make a phone call.

 

[soundguy]

[quote author="nacho459"]I've never heard the Cinimags before, but It looks like they used to have something to do with Altec? Do you just order directly from them?[/quote]

cinemag is run by reichenbach's son, Tom. They have all the old designs on file. Jensen started licensing designs from reichenbach.... In several cases both companies sell the SAME transfomers. Calling them is worth the trouble, youd be hard pressed to find two guys more eager to please. I have all reichenbach transformers on my console and tom was more than excited to dig through the dust to find the old info on the part numbers I provided and wind me new transfomers to match, in this day and age, thats unbelievable service. Amazing guys and the transformers Ive heard from them, then and now are insane sounding. All the old quad eight stuff I think was all reichenbach.

dave

 

[analag]

I used a high head room circuit that lets the transformers sing without getting in the way too much, but as gain increases headroom decreases and all this can be controlled by making R13 adjustable.

the transformers Ive heard from them, then and now are insane sounding. All the old quad eight stuff I think was all reichenbach.

Enough said

 

[NewYorkDave]

[quote author="analag"]
Dave you are correct...theory and sound don't correlate well at all. [/quote]

I didn't say that. There usually is some correlation between good design and good sound. I'm not counting deliberately nonlinear stuff like guitar amps. Theory will tell you if the circuit will work, even if it cannot usually predict subtleties of sound. A wise designer learns and knows the theory--it's a vehicle to get him to his goal more efficiently--but also knows to trust his ears in the final analysis.

 

[Rossi]

Dave, you're an inexhaustable source for cool avatars :thumb: :thumb: :thumb:

 

[analag]

Ok Dave, in this case your theory

The bottom triode in the output stage is just acting as a glorified cathode resistor.

don't correlate well with the sound of this particular preamp.