FRM really nice Compressor vs THAT4301 Pico Compressor

[mediatechnology]

I'm just glad the OP got his question answered...

[JohnRoberts]

Hi and welcome to the fun house.

I appreciate you and Roger sharing your experience and expertise here, especially in response to specific questions.

JR

[theblotted]

so how do these PICO fair with the GSSL's?

[mediatechnology]

They are really two different animals and tools. Three including the SSL.

The Pico is a feed-forward rms compressor. The stereo unit uses true power summing.

There's an article about true power summing here: Pico Compressor Audio Design Forum • View topic - A Discussion About True Power Summing for Stereo Compressors

The GSSL uses algebraic summing (mono sum) at the input to the single sidechain. It is a feedback limiter with a single surrogate sidechain driving both VCAs. The GSSL's detector only "hears" the L+R mono component. The sidechain is sensitive to polarity and phase of the L and R inputs.

The SSL compressor uses two sidechains with their peak detectors combined. This can be characterized as a "greater of two" peak detector. It is also a feedback limiter with the combined detectors driving both VCAs. The SSL acts on the highest peak whether it's in the left or right channel. Because combination occurs after detection it is polarity and phase insensitive. SSLTech's Turbo mod does this for a GSSL.

There's an article on the differences between the GSSL and SSL here:
Pico Compressor Audio Design Forum • View topic - Why A GSSL and SSL Compressor Aren't Exactly the Same

I have never heard a GSSL so I can't comment on it. I used to service and commission SSLs but it's probably been about ten years since I've used one. Both of those are peak responding and well-suited to peak level control.

The Pico, being rms, more closely resembles the auditory response for loudness as it responds to level over time more than peak. It's better suited to increase loudness density.

An optimum combination would be an rms followed by peak. This allows both density improvement and peak level control.

I hope you didn't expect a short answer.

Wayne

[theblotted]

Originally Posted by mediatechnology

They are really two different animals and tools. Three including the SSL.

The Pico is a feed-forward rms compressor. The stereo unit uses true power summing.

There's an article about true power summing here: Pico Compressor Audio Design Forum • View topic - A Discussion About True Power Summing for Stereo Compressors

The GSSL uses algebraic summing (mono sum) at the input to the single sidechain. It is a feedback limiter with a single surrogate sidechain driving both VCAs. The GSSL's detector only "hears" the L+R mono component. The sidechain is sensitive to polarity and phase of the L and R inputs.

The SSL compressor uses two sidechains with their peak detectors combined. This can be characterized as a "greater of two" peak detector. It is also a feedback limiter with the combined detectors driving both VCAs. The SSL acts on the highest peak whether it's in the left or right channel. Because combination occurs after detection it is polarity and phase insensitive. SSLTech's Turbo mod does this for a GSSL.

There's an article on the differences between the GSSL and SSL here:
Pico Compressor Audio Design Forum • View topic - Why A GSSL and SSL Compressor Aren't Exactly the Same

I have never heard a GSSL so I can't comment on it. I used to service and commission SSLs but it's probably been about ten years since I've used one. Both of those are peak responding and well-suited to peak level control.

The Pico, being rms, more closely resembles the auditory response for loudness as it responds to level over time more than peak. It's better suited to increase loudness density.

An optimum combination would be an rms followed by peak. This allows both density improvement and peak level control.

I hope you didn't expect a short answer.

Wayne

no, in fact i was hoping a longer one. thanks for a very simplified explanation, detailed but easy to understand.

i'm about the build a GSSL with the Oxford mod, and the Pico piqued my curiosity.

[mediatechnology]

i'm about the build a GSSL with the Oxford mod, and the Pico piqued my curiosity.

Cool. Kinda wished it had been named the Stonesfield mod since that where the first one was born.

[theblotted]

Originally Posted by mediatechnology

Cool. Kinda wished it had been named the Stonesfield mod since that where the first one was born.

never too late to PM Purusha...

[eskatonic]

Originally Posted by synap2012

FRM really nice Compressor vs THAT4301 Pico Compressor

Hey I have herd the FMR before it sound pretty good, is the Pico compressor in the same ball park as the FMR compressor. or are they two totally different beasts.

Thanks

Hey synap2012,

I just finished build a stereo pico compressor (thanks again for the help Roger) and had a chance to run a drum submix through it this evening. I have also built a couple of GSSLs and do have a FRM compressor - This thread got me curious and wanted to compare the comps doing some drum duty. After running the pico for an hour or so I took it back to the bench and added a pair of Cinemag output transformers I had left over from a project which never materialized. The difference with iron is subtle but it definitely adds some body (not sure what else to call it - the sound is thicker - imagine separating a pair of twins at birth and give them nearly identical lives except you feed one steak-n-corn and the other a traditional San Franciscan vegan diet - The vegan is cool, she's got a great smile but I want her sister with the big ol' booty) to its output. To your question - I would not say one is better than the other but they are absoutely different beasts. I have had plenty of fun creating new sounds/textures with the RNC but I would never strap it across a drum submix (but can be very useful when crushing down room mics to be blended back in). For this particular application the pico is a much better tool.

Sorry Roger - My sense of humor never really evolved beyond elementary school. I tend to replace "Gain" with "Balls" at every available opportunity. This particular setting had no balls at all.

[RogerFoote]

Hi eskatonic

Lookin' good! Thanks for the post.

Roger

[gm5k]

Originally Posted by eskatonic

Sorry Roger - My sense of humor never really evolved beyond elementary school. I tend to replace "Gain" with "Balls" at every available opportunity. This particular setting had no balls at all.

LOL that's hilarious.

[gearaddict]

I cant understand why companies that sell diy kits cant just say...ok this is what you need it costs $xxx..instead of...$3.95 for x, $45.00 for x...and you end up needing all of it anyway!! Just tell me what it costs..yes with the box to hold the boards!

[emrr]

Roger was selling complete kit versions for awhile, and guess what; people get sticker shock when you do that. That's why people sell incomplete packages; it's all that really sells. You can call it stupid all day long, and it doesn't change what people actually spend $ on. There's generally too many variations with most DIY to do a complete kit that will make everyone happy, so almost no one buys them, or they complain about the parts choices, or the color, or the price of the chosen parts, etc etc etc. You could make 10 different price lists for any project, what with specific parts cost and location variables. Never mind the price of all metals has been shooting up constantly for the last 5 years. every time I order from Mouser the online prices are significantly higher than the current print catalog lists, all due to supplier increases. So a total cost is hard to quote as example since it's almost immediately obsoleted.

[anguswoodhead]

So where do I find out info about the Pico 500.
I am not interested in building a kit.
But I could be keen on buying a pre-built Pico 500 for my API rack.
Not interested in the Pico forum - seems to be mainly about the kits.
Is there a website with pricing etc.?

[Drone]

Originally Posted by anguswoodhead

So where do I find out info about the Pico 500.
I am not interested in building a kit.
But I could be keen on buying a pre-built Pico 500 for my API rack.
Not interested in the Pico forum - seems to be mainly about the kits.
Is there a website with pricing etc.?

I had the same problem. -No time to build kits & the forum was all DIY.
Send him an email. I'll pm the address to you.

[anguswoodhead]

Originally Posted by Drone

I had the same problem. -No time to build kits & the forum was all DIY.
Send him an email. I'll pm the address to you.

Got it - e-mail sent.
Cheers.

[RogerFoote]

Originally Posted by gearaddict

I cant understand why companies that sell diy kits cant just say...ok this is what you need it costs $xxx..instead of...$3.95 for x, $45.00 for x...and you end up needing all of it anyway!! Just tell me what it costs..yes with the box to hold the boards!

Your point?

That is exactly what we were doing, complete kits at a single price and also various permutations without panels or other parts to keep cost lower.

We sold 10 kits to 2 very adept builders and that was a pleasure...
We want to extend every support to those adepts and it became clear that if we had kits going out en-masse our support time could easily outweigh the time it takes me to build said item, and also bog down our support response which is without complaint at this juncture.

Also, the Pico forum does have a lot of DIY info but has always been where I introduce new products as I design them.

The Pico 500 was just released, just. We haven't had time to build the website or any of that yet, but it is being worked on very hard and will be there soon. Our main problem is that sales are so strong that we barely can keep up.

Not being a "big corporation" means that there are a couple of human beings bulding, calibrating, testing, packaging and shipping the products and only 24 hours in a day. The Pico 500 is a hand built piece of gear and every unit gets my personal scrutiny, so your patience and support are greatly appreciated!

Very best regards

Roger Foote

Foote Control Systems

[mediatechnology]

I cant understand why companies that sell diy kits cant just say...ok this is what you need it costs $xxx..instead of...$3.95 for x, $45.00 for x...and you end up needing all of it anyway!! Just tell me what it costs..yes with the box to hold the boards!

Heathkit did that R.I.P. There aren't many left that do.

On the DIY equation:

I find that most people would rather not pay me to count out 1% resistors for them. If anyone would like to give me that job I'll be glad to do it: My rate is $75/hr.

LED or analog? Some people want different meters or already have a power supply. Maybe they can't use the switchboard because they're building it into something else where it won't fit. Some people already have their THAT ICs.

The volumes just aren't there to buy the kind of quantities of "stuff" from Mouser to get pricing that the average kit builder would think is a better deal when they could just buy them directly.

Some people don't want to spend all the money at once because they can't afford it. So they buy the boards, ICs and passives, build it, listen, and then buy the case later.

DIY is a build your own burger bar.

As to the 500 I put it on the DIY forum so people could at least see it. As I write this I'm waiting for UPS to deliver the first ones...

[mediatechnology]

By the way Angus thank you for contacting Roger and me.

Wayne

[JohnRoberts]

I ran a kit business back in the '70s when it was IMO a good business model. Heathkit was at one time doing a $100M gross annual sales. The bottom fell out of that market when automation lowered the labor cost fraction of new product cost. So now kit businesses are far less economically advantaged.

I suspect Roger's efforts are more a labor of love than an out right commercial venture.

JR

PS: Wayne.. A few stories about counting out resistors... when I did my first kit in '76 it had something like 50 resistors in each kit... I recall it talking a long ass time for me to kit up my first hundred kits... I later came up with the method of covering a table top with say 50-100 plastic cups, and dropping the resistors (or whatever) into the plastic cups. Then later transferring the cups total contents into plastic bags in a single step.

Heathkit in their later days were actually using automation sequencing machines to generate resistors on a tape and reel format. These machines are actually part one of a two step process used in one early form of machine insertion. First a machine sequences the axial components onto a reel, then a second machine takes those parts from the reel and inserts them... (modern machines just load tens of different components and pulls them as needed to insert/place). Heathkit cleverly used the first machine to kit up their axial parts.. But they were still toast due to the compromised economic model... RIP.

I bet somebody today could buy one of those obsolete sequencing machines pretty cheap... hmmm. However be warned the machines were huge to hold a lot of values IIRC 10-15' long.

[mediatechnology]

PS: Wayne.. A few stories about counting out resistors... when I did my first kit in '76 it had something like 50 resistors in each kit... I recall it talking a long ass time for me to kit up my first hundred kits... I later came up with the method of covering a table top with say 50-100 plastic cups, and dropping the resistors (or whatever) into the plastic cups. Then later transferring the cups total contents into plastic bags in a single step.

Thanks John. I've done that in the past too. Now if I can just find someone to pay me the hourly rate...Or for that matter see them w/o eyestrain.

I've put a disgronificated (to prevent spam) e-mail link in the 500 "Build" post over at the Pico Compressor Forum so people can just e-mail me. Like RF said we haven't had time to do a proper web page for them.

[mediatechnology]

UPS just delivered them to me.

Pico Compressor Audio Design Forum • View topic - Limited Qty Assembled Pico 500 Units Now Available

I've put an e-mail link into that post for those wish to contact me.