Valve Mic Pre comp kit wish list & discussion

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Valve Mic Pre comp kit wish list & discussion

Post by Joe Malone »

SMPS TUBE POWER.jpg
REDBACK.jpg
TAIPAN.jpg
This is a general thread to discuss the coming soon Aussie Dangerous animals tube mic pres & compressors & SMPS tube power supply.

So far testing is going well for our REDBACK 47 type mic pre and Taipan Pultec MB1 type mic pre running on our SMPS tube power. These 3 kits will be the first to be released.

First Sound Samples at the link below
https://soundcloud.com/jlmaudio/sets/re ... re-samples

I am looking for ideas on any other in and out transformers users would like the PCBs to take and any other features users would want. So other tube mic pres and compressors that users are wanting

So far REDBACK and TAIPAN PCB can take

Input transformers
JLM1:4
OEP A262A3C, A262A2E, A262A3E, A262A6E, A262A7E.
Vigortronix VTX-102-001, VTX-102-002, VTX-102-003, VTX-102-006, VTX-102-007
Lundahl LL1538, LL1538XL, LL1576, LL1577, LL1578XL.
Jensen JT-11K8-APC, JT-110K-HPC, JT-115-EPC, JT-MB-CPCA .
Beyer 8mm threaded bolt types.
Cinemag CM-75101APC, CMMI-8-PCA.
API Classic EA2622.
Sowter 9970 Size J Style e (9.5mm hole mount)

Output transformers
Cinemag CM-2810, CM-2820, CM-2830, CM-2840, CM-27101 in either PCB mount or frame mount.
Sowter 9980 Size J Style e (9.5mm hole mount)
Edcor WSM15K/600 frame mount
*Trying to add Jensen JT-10k61-1m frame mount

I have started PCB designs for
Gates M2515 & M2515A mic pre.
Altec / RS Mu compressor.
Fairchild 670 audio path with separate sidechain pcb.

Wish List
175 Mu comp
V72 Mic Pre
610 Mic Pre
Altec 458a
Ampex 351 Mic pre
V76 Mic pre
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Joe :-)
JLM Audio
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mylesgm
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Re: Valve Mic Pre comp kit wish list & discussion

Post by mylesgm »

These look so cool!

I'd love to be able to use trimax transformers for I/O though I expect that's possible but off board mounted.

Compwise it'd be cool to see something outside the more common options, a 175 maybe?
And what about inserting a passive eq into the circuit, a baxandall or a more complex style?

With the SMPS can it do +24v and +130v?

Joekkel
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Re: Valve Mic Pre comp kit wish list & discussion

Post by Joekkel »

wow! count me in for a stereo 47 and mu compressors! your support has always been top notch!

PeterBregman
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Re: Valve Mic Pre comp kit wish list & discussion

Post by PeterBregman »

These look awesome. What's the story with the toroidal OT's you're using in the prototypes?

If you're looking for other ideas for tube circuits, it would be great to see another option for a V72-style preamp, or a take on the original Putnam 610. I'm also very interested in a stereo Altec/RS Mu compressor, so it's great to see that you're working on boards for that. :D

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Re: Valve Mic Pre comp kit wish list & discussion

Post by Joe Malone »

mylesgm wrote:These look so cool!

I'd love to be able to use trimax transformers for I/O though I expect that's possible but off board mounted.

Compwise it'd be cool to see something outside the more common options, a 175 maybe?
And what about inserting a passive eq into the circuit, a baxandall or a more complex style?

With the SMPS can it do +24v and +130v?
175 added to wish list. Yes trimax transformers will no fit.

SMPS power supply standard has +12.6v, 0v, 12.6v, 70v, 125v, 180v, 235v, 290v, 345v but can easily be turned up of down several volts.

If you cut one 0v track you could make it 0v, 12v, 24v, 73.5v, 130v easily. Or just change one 12.6v SMPS to 24v type.
Joe :-)
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Re: Valve Mic Pre comp kit wish list & discussion

Post by Joe Malone »

Joekkel wrote:wow! count me in for a stereo 47 and mu compressors! your support has always been top notch!


:D 8)
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Re: Valve Mic Pre comp kit wish list & discussion

Post by Joe Malone »

PeterBregman wrote:These look awesome. What's the story with the toroidal OT's you're using in the prototypes?

If you're looking for other ideas for tube circuits, it would be great to see another option for a V72-style preamp, or a take on the original Putnam 610. I'm also very interested in a stereo Altec/RS Mu compressor, so it's great to see that you're working on boards for that. :D
V72 & 610 added to wish list

Toroids are just experiments at the moment but working very flat 20hz to 20khz but low ratio one has a peak at about 100khz which I am trying to fix. High ratio one is flat to 100khz. They have a spare feedback winding which would work good for some of the UA and other tube pre designs.
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Danbonefinger
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Re: Valve Mic Pre comp kit wish list & discussion

Post by Danbonefinger »

What about an Altec 458a?

This is all really cool!

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Re: Valve Mic Pre comp kit wish list & discussion

Post by Joe Malone »

Danbonefinger wrote:What about an Altec 458a?

This is all really cool!
458a is more like a low gain balanced booster but I will do some computer simulating to see how much gain to could be made to do.

458a added to wish list.
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Jrasia
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Re: Valve Mic Pre comp kit wish list & discussion

Post by Jrasia »

Ampex 351?

leitmo
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Re: Valve Mic Pre comp kit wish list & discussion

Post by leitmo »

Hi Joe,

I'm in for a couple of RS Mu compressors.
- stereo linking would be a feasible option?
- attack/release?
- sidechain filter? Not only HPF but some MF/HF boost like API2500
- I'm not into MS compression but it'd be easy to add an encode/decode interface

I'm very curious about that 670 signal path with separate sidechain PCB? it's a compressor? Just a line level processor modeled after 670?

mdmitch2
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Re: Valve Mic Pre comp kit wish list & discussion

Post by mdmitch2 »

Can you tell us a bit about the gates m2515? Either my googling skills have gone downhill or it's a pretty obscure piece of gear. :)

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Re: Valve Mic Pre comp kit wish list & discussion

Post by Joe Malone »

Jrasia wrote:Ampex 351?
Ampex 351 added to list
Joe :-)
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Re: Valve Mic Pre comp kit wish list & discussion

Post by Joe Malone »

leitmo wrote:Hi Joe,

I'm in for a couple of RS Mu compressors.
- stereo linking would be a feasible option?
- attack/release?
- sidechain filter? Not only HPF but some MF/HF boost like API2500
- I'm not into MS compression but it'd be easy to add an encode/decode interface

I'm very curious about that 670 signal path with separate sidechain PCB? it's a compressor? Just a line level processor modeled after 670?
Ok your list above it very similar to my thinking as I don't make any clone unless it can be way better than the real thing with many more options and improved signal to noise etc.

The 670 audio path pcb will take 4 x 6386 or 8 x 6BA6 tube and in and out transformers and M/S in and out relay switching.

Sidechain will be solid state with insert but will have step up output transformer so attack and release and bias adjust work as original.
Joe :-)
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Re: Valve Mic Pre comp kit wish list & discussion

Post by Joe Malone »

mdmitch2 wrote:Can you tell us a bit about the gates m2515? Either my googling skills have gone downhill or it's a pretty obscure piece of gear. :)
Gates M2515 / A is similar a Gates SA-70 but with miniature 9 pin tubes.

SA-70 uses octal 6J7 pentode and 6C5 triode but both are used as triodes

M2515 uses 2 x 5879 pentodes as pentode input and triode output

M2515A uses 2 x EF86 pentodes as pentode input and triode output

Idea would be to be able to switch from pentode to triode input circuit (M2515 to SA-70) and use 5879 or EF86 tubes.
Joe :-)
JLM Audio
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