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Sum Comparison (folcrom makeup gain) 500 Series Preamps
Old 14th September 2011
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rhythminmind's Avatar

Sum Comparison (folcrom makeup gain)

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Got my hands on a pair of JCF LEVRs. I wanted to see how they compare to my usual “go to” API 312 for makeup gain after the folcrom. After a week of pulling my hair out trying to get the LEVRs to play nice with my setup, (more on that later) they do have a nice presence that sets them apart.

For this comparison I mixed a quick ITB drum mix. Then sent the individual drum channels (16) to the FOLCROM/One of the listed makeup gain amplifiers.
What do you prefer out of the group?



LEVR via input Transformers

API 312 pre

As I said it was a bitch getting the LEVRs setup properly. I noticed severe distortions when the LEVR received signals for most of my converters/outboard. LOOONG story short LEVRs with the transformer output option need to see “symmetrical balanced” signals. Many balanced devices only send signal down the + leg. This for some unknown reason really makes the LEVR with the output transformer unhappy. Thanks to the help of Bill Whitlock & my curiosity I found two solutions.
  1. Add transformers before the LEVR. Bill recommend the JT-MB-CA
  2. Disable the output transformer.
I’ve tried both & opted for solution 2.
Old 9th April 2013
Gear Head

Very interesting shootout, many thanks for taking the time to do it and posting it.

However, levels were a bit hotter on both JCF files, that explains your choices.

Once you match levels the differences are almost negligible. I picked the API a few more times then the others when i did blind tests (with levels matched), but it wasn't a very consistent pick anyways.
Old 15th April 2013
Gear Head
Fishnmusician's Avatar

You might try some SL2520 Red Dot op amps in the 312's. Not sure which 312 you are using. I put red dot's in my 212's and sent the JCF w/tran back.
I liked everything about the Levr except the sound, even after 24hr burn in.
The 212 with stock modern day op amp's where unusable in my Folcrom. What a big surprise with Red Dot's, amazing depth and detail.
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