• Get involved.
    We want your input!
    Apply for Membership and join the conversations about everything related to broadcasting.

    After we receive your registration, a moderator will review it. After your registration is approved, you will be permitted to post.
    If you use a disposable or false email address, your registration will be rejected.

    After your membership is approved, please take a minute to tell us a little bit about yourself.
    https://www.radiodiscussions.com/forums/introduce-yourself.1088/

    Thanks in advance and have fun!
    RadioDiscussions Administrators

Breakaway Broadcast Processor

I'm certain that with enough adjustment (more range, more power, more speed than I run) it would have perfect control on B & W.

I did try to run that way when I first began using BBP, but found the sound too "dry" for my tastes.
The ART adds a wetness, that can only be distortion, but to me it makes the radio sound like a hot, muggy summer night in 1966.

I admit it's distortion, but as long as it sounds like the giant AM Rock-n-Roll powerhouses of yesteryear, I'm happy.
No grunge, no gristle or bristle, just sweet and wet with a sharp bite like an old fashioned ice-cold cane sugar Coca-Cola from a glass bottle.
It's been maybe 9 or 10 months now, and it just keeps running with no burps or hiccups.
There is no longer any reason for me to fiddle with anything. Everything sounds good from symphonic music to punk, and everywhere in between.

There's no fatigue, no temptation to tweak. The 150% asymmetric modulation is nothing short of KICK-A**.

I was "happy enough" with the ART for outright level control, but it does nothing for mulitband level control, so when BBP hands a well-balanced
signal to the ART, its job is a LOT easier, and there's no hiding of musical details in the result.

The song I find shows off good or bad control is "I Hear You Knocking" by Dave Edmunds.
The first few notes have enough wide range to flummox any cheap processing, and makes them sound like like a drunk looks when taking a wild swing at someone's jaw and missing completely, and falling over to the floor in a mess, wondering what happened.

BBP sounds outstanding on this cut, I can't say enough good about it. And I'm a "hardware" kinda guy.
 
I'm moving closer and closer to getting BBP on the air...just have to finish this pesky sports automation crap for our AM.. Leave it to Learfield Sports to not stick to their format - has caused me all kinds of hell.
 
I put BBP on the air tonight, seems to be working great so far, only quirk is I need to put a 6db pad in line with the input, audio is just a bit on the hot side I would prefer more headroom. Any advice on just where I should shoot for the input level to be? I'm thinking around -12db which is right where I've seen it recommended to run the input on the DSPXTRA and Omnia One.

As it is, it sounds great just a slight bit hot on some spots. peak control is great as well. I'll report back more soon, I'm still trying to find a good copy of Black & White to try out, I wasn't able to find it on the onair PC, Most of the files on there are not tagged, the owner knows what most of them are by the file number, I do not. He is supposed to find it for me.
 
Hi guys!

Looks like I need to visit more often, can't believe I missed this thread. Thanks for all the great comments!

Bob, I have finally tested Three Dog Night - Black and white, and you know what -- I see the problem!

The original audio contains subsonic material in the form of an asymmetric bass waveform.

The clipper itself has no problem with this, and does its job perfectly. Clipping itself may also add subsonic material, but usually not enough to cause problems. The problem happens later in the chain -- The capacitors in the sound card do their best to *remove* the subsonic components of the audio, and when they're removed, the whole waveform can actually shift!

Check out this video. BBP ASIO, EMU 0202 (Tilt +4, Coeff -30), Twente preset (worst case! No adaptive bass clipper in this preset), Final Drive +1.0, Bass Boost +25, HPF *OFF*. I ran it in mono mode for clarity, so that you clearly see the clipped edge.

Watch the edges carefully, and compare to the grid lines.

http://bredband.leif.cx/browse/bbp_hpf/hpf_off.mpg


We were asking the hardware to do the impossible. As the capacitor after the output dac pulls the waveform in one direction, the tilt correction algorithm pushes the audio in the other direction to compensate. This works well for audio frequencies, but when there's subsonic in the audio, it's just impossible -- we don't have infinite headroom, and we really would need an infinite amount of power at infinitely low frequencies!


There is good news though. See what it looks like with HPF at 30 hz!

http://bredband.leif.cx/browse/bbp_hpf/hpf_30hz.mpg

By removing subsonic from the original audio, the tilt correction now only has to deal with clipper-induced subsonic, which is much less.



Although, even with HPF off, I didn't see 20% of overshoot, I saw less than 10%. I believe a waveform like this is tough for ANY equipment, so it's *possible* that the exciter or the mod monitor are exascerbating the problem. The BW PLL+ 1W exciter has exemplary low frequency response though (it's flat down to a single hz as measured with a scope hooked up to a belar wizard.. amazing), so it definitely wouldn't be my first suspect.


So, in conclusion:
I need to modify the software to disable and grey out the tilt control slider when HPF is set to Off, as it's obviously instilling a false sense of security. Basically, to run HPF Off, you're going to have to use a DC straight sound card. This wasn't clear before.

Thank you very much for bringing this to my attention, Bob! It's incredibly heartwarming and reassuring that people are actually paying attention :).

Best regards,
///Leif
 
Well...after some encouragement from Leif, I took the plunge & purchased a DC coupled sound card...the Marian Trace Alpha. The word WOW somehow falls short as a descriptor. BBP is a product that's brutal when applied to non-DC coupled sound cards & exciters with poor low frequency response. The Marian card into the Broadcast Warehouse exciter has peak control that is nothing shy of amazing. Even with the LPF turned off & the torture test song Three Dog Night - Black And White played with a full +50 bass boost (absolutely no one wants that much bass...but just in case, it's there) produced a whopping 2% overshoot. I knew that BBP was a killer product, but until I ran it with a DC coupled sound card, it's excellent design was not being fully revealed. And if that isn't enough, the clip level can be run nearly 1db higher without audible distortion. If you're running this on an LPFM, you may not be able to justify the cost of the card. But for the record, the right sound card takes BBP from a great LPFM contender to one that is truly ready to play with the big boys. Sorry if I sound like I'm writing a review, but I am genuinely impressed at what I'm hearing & seeing.

http://www.marian.de/en/products/trace_alpha
 
I'm glad you're excited. Although, armed with the right test gear and a very proper way to look at total modulation...I would disagree with your view that BBP is limited to just lpfm use...its an extremely powerful package in its own right.

Heck, if the suits didn't think using a computer as an on air processor was somehow a bad thing, I would have bbp on all of my stations! Using a high quality card and components of course.

On my first critical listen, it was obvious that it just sounds better than other boxes.

Its time will come eventually.
 
I see no problem with using a PC as the processor, of course with high quality components and a solid state drive. I see no reason it would be any less reliable than a "hardware" processor thats nothing more than a custom computer running software.


I never got past some initial testing with a trial version of BBP ASIO, station owner decided there was no advantage to replacing the $5k box that's out there now.. when I do it over again i'm going to get that marian card, m-audio audiophile 192 was not quite as good as i had seen it described even with additional caps on the inputs and outputs.
 
BobOnTheJob said:
Well...after some encouragement from Leif, I took the plunge & purchased a DC coupled sound card...the Marian Trace Alpha.
Do I understand correctly that the Trace Alpha's output is just as straight as the Trace 8? So no need for Tilt Compensation and PEQ (as far as the soundcard is concerned)???
 
richard.vanderveen said:
BobOnTheJob said:
Well...after some encouragement from Leif, I took the plunge & purchased a DC coupled sound card...the Marian Trace Alpha.
Do I understand correctly that the Trace Alpha's output is just as straight as the Trace 8? So no need for Tilt Compensation and PEQ (as far as the soundcard is concerned)???
Correct. I asked Marian more than once to confirm that the Trace Alpha had the same DC Coupled Output as the Trace 8. Each time, I got the same answer. When running the 60hz Square Wave on BBP, the Tilt Compensation is best at zero and the modulation meter dips into the low 70's. It's indeed the real deal and available for 139 euros.
 
Now I am thinking about another computer to run the musicserver and BBP low-latency on.
Nothing else. I have been very happy with how a laptop has worked with power burps, but can't
very well just stick another sound card in a laptop.
I have an "idle but on the network" 2006 built-like a tank steel Japanese industrial OEM desktop now with a steam-engine processor and W2000, but a nice built-in UPS. Audio and BBP run on an old IBM Thinkpad with a broken LCD backlight (impossible to use, I control it on a remote desktop application, IntelliAdmin).
Should I put in a new processor card and the DC-coupled audio card, or consider a cheap new Dell desktop system?
There are "some" issues with the built-in UPS switching mode noise, or some kind of heterodyning RF getting into the audio, but not too bad. Way down but audible.
I didn't want to go Vista, but now that that's not necessary, I'm open to sugestions.
It's been years since I switched out PC cards a la carte. At least this box has the newer "small" edge connectors, and is full depth.
I'd love to hear recommendations.
 
Sgeirk said:
I'm glad you're excited. Although, armed with the right test gear and a very proper way to look at total modulation...I would disagree with your view that BBP is limited to just lpfm use...its an extremely powerful package in its own right.
Let me clarify my comment about BBP being suited for LPFM use : In the USA, FM peaks of frequent recurrence can not exceed 100%. With a non-DC coupled sound card, playing the song Black And White by Three Dog Night results in well over 120% modulation (there are also other songs that aren't quite as over the top). As a result, to be safe & legal using a non-DC coupled sound card, it's my belief that BBP's average modulation would need to be set to about 75%. That condition pretty well removes BBP from use in all but the least competitive situations. Make no mistake, BBP sounds better than the Omnia's & Orban's. The 75% issue is through no fault of BBP other than the fact that it's capable of operating with sound cards you can buy new on eBay for $30. Like driving a Ferrari over a rickety old country bridge...you're not going to be able to max it out. It's a shame that DC Coupled sound cards are such a rarity. The other side of the coin is that the brains of the processor are less costly than the preferred sound card...and that is a powerful testament to BBP's value.
 
If you mean that LPFM's don't have any way to possibly measure audio on a scope or have a calibrated mod monitor, then, you're right.

Otherwise, it's easy to set tilt for the card on a basic scope. It really has little to do with the soundcard and everything to do with just having appropriate gear.
 
Sgeirk said:
If you mean that LPFM's don't have any way to possibly measure audio on a scope or have a calibrated mod monitor, then, you're right.

Otherwise, it's easy to set tilt for the card on a basic scope. It really has little to do with the soundcard and everything to do with just having appropriate gear.
True on most songs, but as Leif noted, the song in question has asymmetrical sub audible bass that the tilt compensation is ineffective for. The entire waveform shifts resulting in negative over modulation while the positive peaks are unaffected. Even using a constantly repeating loop of the offending piece while observing the negative overshoot on a scope while adjusting the Tilt compensation results in zero improvement. I've challenged others on here using a non-DC coupled sound card to play Black & White with a +50 bass boost and watch the negative peaks go well past 120%. With the exception of Leif, no one tried it. Leif observed what I was observing & convinced me that the only cure was a DC Coupled sound card...he was dead on.
 
Status
This thread has been closed due to inactivity. You can create a new thread to discuss this topic.


Back
Top Bottom