Help choosing compressor pedal

[buildafriend]

I need one with a medium compression that is very transparent. Advice please? What would you build. Its for a guitarist in a prog rock band.

[Mark Hammer]

What does he need it to do for him?  Is he looking to hold notes forever?  Looking to thrash around on rhythm and not overshadow the singer?  Different compressors are good at different things.

[JebemMajke]

I would like the one with notes forever please.

[buildafriend]

I gave him the whole list of pedals that are available in the schematics section on here, he is trusting my advice. I am a builder and recording engineer, not a guitarist. All he said is he wants transparency and that its for progressive rock. He knows less than I do which pedal is best for him. All I really know is what he is describing( transparent and medium compression that is flexible). If i talk to him further he will probably change his mind. I can sort of sense it. I would rather make a few bucks for the build than batter him with questions and technical advice.

[Mark Hammer]

You could fill up a truck with the posts that bat around the term "transparent".  So, I don't wish to disparage your friend or your own fairly straightforward objectives, but "transparent" doesn't really point in any direction.

The only thing I can think of is that many guitar players whine about the loss of top-end bite when using a compressor, not realizing that it's a bit like saying "I want a swept bandpass filter...but one that doesn't lose any bottom"; i.e., it comes with the territory.

If your own goal is to get in and out quickly, the cobble together an Orange Squeezer.  A stock unit has a fairly fast gain recovery, such that it operates a little more like a limiter and less like a compressor to many ears.  Since you're a recording engineer, you'll understand that faster gain recovery allows a flurry of notes to retain a fair amount of their original snap, without being dragged down by the gain reduction elicited by that first picked note.  Many "famous" guitarists over the years have described the OS as more "transparent", so maybe that's what you want.

I whipped up a modded OS some years ago that I frivolously named a "Tangerine Peeler".   One of the members here took it up a notch and produced a very thoughtful version of what I had suggested.  You can find it in this thread:  http://www.diystompboxes.com/smfforum/index.php?topic=70771.0   I think there's your winner.

[Philippe]

I need one with a medium compression that is very transparent.

I am a builder and recording engineer....All I really know is what he is describing( transparent and medium compression that is flexible).

You could fill up a truck with the posts that bat around the term "transparent".

If your own goal is to get in and out quickly, the cobble together an Orange Squeezer.... Many "famous" guitarists over the years have described the OS as more "transparent", so maybe that's what you want.

Being a recording engineer you are probably familiar with the Joe Meek rack compressor. It is also available as an external 'stompbox' (the Joe Meek Floor Q Optical Compressor) for around $250.00. It's about as 'transparent' as one can get although I've never seen a DIY version.

The OS is also a terrific compressor. It's a relatively simple build & depending on how one 'trims'  it (bias adjustment), you can get an operational range that runs from noticeable squashing to mild overdrive (with less compression/squashing effect). In full compression mode it can take a fading/decaying note & give it a 'blooming swell' (for lack of a better description) with an attack emphasis on the leading note. To some (myself included), the OS is more of an 'effect' than a conventional guitar compressor. It has a personailty all its own which differs it from others (i.e. Ross/DynaComp etc.).

For more of an 'invisible hand' the Joe Meek will probably be the most neutral & transparent providing it is adjusted properly.

[petemoore]

  Dyna, or Ross, I like this with almost none of the HF filtering at the end, can be quick to almost too slow for rock, can be further slowed before the ramp starts 'laying-1/2 stuck along the bottom of the gain sweep'. Pretty effective sweep/range control using the transductance amp.
   Any other one except OS, unless the OS-mod circuit for heavier comp sound acheives 'medium compression', I like the OS for it's transparent comp-ness and barely-distorting, 'silky' nature.
  The thing about photocells is they're photocells so it either makes it easy [in that they smooth ramping naturally, and the design seemed straightforeward to me] or hard [in terms of whether your'e able to get the ramp/range close to what you want.
   They're different in ways that tend to include the universal truths of what 'compression' application includes:
  More attenuation/gain sweep = volume gets to cranking the noise up with no input.
   The rest is subjective really, about ramp rates and frequency response [IMO, if the actual circuit sounds good.
  Asfaras which chip to reduce noise with, it's hard for me to imagine how any chip noise could exceed the inherent noise created when applying compression to guitar pickup/cable source.
   

[ayayay!]

I'm not one to pimp anything but DIY stuff,  () but you might have him check out the Aphex Punch Factory.  It's optical based, and is ridiculously quiet.  A modified CS-3 can easily be made to be quite transparent. 

You said prog, so I'm thinking prog like Petrucci, Morse, Yes, etc...

[buildafriend]

I need one with a medium compression that is very transparent.

I am a builder and recording engineer....All I really know is what he is describing( transparent and medium compression that is flexible).

You could fill up a truck with the posts that bat around the term "transparent".

If your own goal is to get in and out quickly, the cobble together an Orange Squeezer.... Many "famous" guitarists over the years have described the OS as more "transparent", so maybe that's what you want.

Being a recording engineer you are probably familiar with the Joe Meek rack compressor. It is also available as an external 'stompbox' (the Joe Meek Floor Q Optical Compressor) for around $250.00. It's about as 'transparent' as one can get although I've never seen a DIY version.

The OS is also a terrific compressor. It's a relatively simple build & depending on how one 'trims'  it (bias adjustment), you can get an operational range that runs from noticeable squashing to mild overdrive (with less compression/squashing effect). In full compression mode it can take a fading/decaying note & give it a 'blooming swell' (for lack of a better description) with an attack emphasis on the leading note. To some (myself included), the OS is more of an 'effect' than a conventional guitar compressor. It has a personailty all its own which differs it from others (i.e. Ross/DynaComp etc.).

For more of an 'invisible hand' the Joe Meek will probably be the most neutral & transparent providing it is adjusted properly.

Weird the Joe Meek stuff is usually cheap.

[Philippe]

Weird the Joe Meek stuff is usually cheap.

If money is no object, then you can always opt for something along the lines of a Manley Stereo Variable MU Limiter Compressor...only $4K (as compared to $275.00 for a Meek rackmount) although it probably won't fit into a Hammond 1590BB enclosure.

the factory details...
The Manley Stereo Variable Mu Limiter Compressor has been Manley's best selling product for many years. It is one of the very few compressors that has become a real standard in Mastering studios and contributed to most hit records over the last decade and probably the next. "Mu" is tube-speak for gain, and Variable Mu is our registered trademark for this limiter compressor. It works by using the "remote cut-off" or re-biasing of a vacuum tube to achieve compression. The precious vintage Fairchild 670 also uses this technique and is one of few all-tube compressor to do so, that we know of. Even the side-chain has glowing rectifier bottles. How's it work? The unique 5670 dual triode is at the center of the peak-reducing and compression action constantly being re-biased by the vacuum tube rectified side-chain control voltages which cause this tube to smoothly change its gain. Just like that.

The COMPRESS mode is soft-knee 1.5 to 1 ratio while the sharper knee LIMIT mode starts at 4 to 1 and moves to a more dramatic ratio of 20 to 1 when limiting over 12dB. Interestingly, the knee actually softens as more limiting is used. Distortion can be creatively used by turning up the Input and turning down the Output while using very little or no compression.

You might notice that the Variable Mu Limiter Compressor has a ganged input control, but do not jump to conclusions that it is mono-unfriendly. Track away! There are separate threshold and output controls to make compensations with plus you can always adjust your individual source levels elsewhere, right? The advantage of the stereo input control becomes dramatically clear when you switch to LINK mode, and that's what our Variable Mu Limiter Compressor does better than anything else: final mix, 2-track, or mastering limiting and compression. Like one reviewer put it: "It's like pouring a bowl of sweet cream over the mix." Mmmmmm. Yummy. Give your music a big hug.

The High Pass Side Chain is included and controlled by two switches to the front panel, one for each channel, so that when engaged, the side chain will not respond to frequencies lower than 100Hz. Manley standardly use 100Hz as the -3dB point. This HP SC can be used with music with heavy bass lines or bass-heavy mixes where you don't want the bass driving the whole action of the compressor.

The filter is a very gentle 6db per octave 1 pole filter, and will typically be down 1-3db at 100 Hz, and down 4-6db at 50Hz. As you decrease the frequency the amount of limiting will decrease also. At the extreme LF (<20hz) there should be very little gain reduction going on. The whole intent of the filter was to keep very LF stuff (like a heavy kick drum) from activating the compression/limiting so that the overall level didn't duck with every drumbeat.

Manley Stereo Variable MU Limiter Compressor Features & Specs
•MANLEY input & output transformers with nickel laminations in mu-metal cases with flat frequency response from 20Hz-25KHz
•BALANCED INPUTS & OUTPUTS (600 ohms)
•Fully differential ALL-TUBE circuitry using one each 5670, 5751, 7044 or 5687, & 12AL5 per channel
•Independently regulated B+ and Heater supplies
•Hard-wire BYPASS switch
•Silent conductive plastic dual INPUT attenuator
•RECOVERY 5 steps: 0.2s, 0.4s, 0.6s, 4sec., 8sec.
•Variable ATTACK: 25msec-70msec
•Continuously variable THRESHOLD
•LIMIT (4:1 to 20:1) or COMPRESS (1.5 to 1)
•Large ILLUMINATED Sifam METERS (older units before serial number MSLC61642 shipped before 12/2003 use: 26V 1.2W FESTOON LAMPS; Manley's Part Number: VAR016B) Order spare bulbs using our parts order form. (newest units after serial number MSLC61642 shipped after 12/2003 use white LED lighting)
•STEREO LINK SWITCH
•Several units can be linked for Surround (custom order )
•Maximum gain: 35dB
•Max. output: +30dBu (26Vrms) 26dB Headroom
•<0.1% THD @ 1KHz Noise floor: -85dB typical
•Power Consumption (120/240VAC): 80 watts
•Unit is factory set for 100V, 120V or 220-240VAC operation for original destination country's mains voltage.
•Operating Mains Voltage changeable with power transformer changeover switch and fuse value change.
•Mains Voltage Frequency: 50~ 60Hz
•Dimensions: 19" x 3 1/2" x 10" (chassis occupies 2u) Power transformer protrudes 3.5" out the back of the chassis.
•Shipping Weight: 23 lbs.
Manley Stereo Variable MU Limiter Compressor Mod Options
MS Mod
Manley offer a Mid/Side mod upgrade (aka. Vertical/Lateral or Sum/Difference) to the Variable Mu Limiter Compressor, which opens the door to stereo encoding and decoding as well as exciting image enhancement processing capabilities. For instance, setting to compress only the in-phase information allows the augmentation of the stereo image as the out-of-phase content is left untouched. Or, conversely, if you need a "more-mono" mix for broadcast, or vinyl-cutting for instance, you can set it to kill off more of the out-of-phase info which leaves more in-phase material in the final result.

Note: There is no space to have both M-S and the HP SC mods, so you have to pick one or the other.

T-Bar Mod
Newer Manley Variable Mu Compressors use the 5670 tube instead of the 6386. In terms of sound, up to about 6db of limiting it's about the same for these two tube types. After that point, the 5670 version tends to sound more "squashed" than the original 6386 version. Some like it better, some don't-- depends on what you're trying to do. To solve all these problems, Paul at Manley came up with a really good solution: The T-Bar Mod.

The T-Bar Mod uses a pair of 6BA6 pentodes wired as single triodes to replace each dual triode 5670 (or 6386). the 6BA6 TBAR Mod is the preferred system to use in the Manley Variable Mu for reasons of ability to perfectly match each phase-halve section and each stereo set, ability to select for lo-noise and lo-microphonic sets for a low cost, and because the action of the 6BA6's so closely resemble the smooth 6386 limiting curves. In other words, the T-Bar Mod converts later 5670 units to have the same limiting characteristics of the original 6386 for smoother operation.

[Jazznoise]

Can I ask why people insist upon "transparent" compression when compression is an intention alteration of the sound? If you want more sustain but don't want compression surely a volume pedal is the way to go? If you're looking for a player to keep his levels pretty consistent I might direct you to his right hand.

In styles like funk it's that clacky compression that makes the sound, if you got the compression but not the "bite" to the pick attack it'd be an errand in futility. Compression, when done right, adds character to a sound. It is a form of distortion after all.

As an audio engineer you should also know that if you have a fixed threshold and ratio compressor (Like alot of the old ones) then you vary your amount of compression by varying the input volume! Since most guitar compressors have 2-3 knobs I'd try varying the input signal and see if there's a point where you like how much it's squishing the signal. Some guitars are hotter than others and asuch an Orange Squeezer might smash a Warrick with active humbuckers but barely touch a Strat with old pickups.