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DORROUGH DAP 310

S

Steve-E

Guest
Anyone have a manual for one of these? A copy would be fine.
Also, if anyone has any thoughts on these 70's vintage boxes, I'd like to hear them.
 
> Anyone have a manual for one of these? A copy would be
> fine.
> Also, if anyone has any thoughts on these 70's vintage
> boxes, I'd like to hear them.
>
Go to your friendly garden store and buy a nice flowering tree.

Dig a large hole.

Put the DAP in the bottom.

Then the tree's root ball on top of the DAP.

Add dirt. ;-)
 
> > Anyone have a manual for one of these? A copy would be
> > fine.
> > Also, if anyone has any thoughts on these 70's vintage
> > boxes, I'd like to hear them.
> >
> Go to your friendly garden store and buy a nice flowering
> tree.
>
> Dig a large hole.
>
> Put the DAP in the bottom.
>
> Then the tree's root ball on top of the DAP.
>
> Add dirt. ;-)
>
No No No.....don't treat that poor littl' ol' DAP that way!
You must not be old enough to remember when the 310 first came out. The world was awash in LevelDevils and Volumax's, with most major market stations cascading anywhere from 3 to 10 units with progressively faster attack/release times. Usually drug the audio across a couple of diodes after that, followed by a crude RC filter. But then, half the AM stations in the USA couldn't modulate positives above 70%, so who noticed.
The times were cool but the waves were square!!
The DAP was an amazing "contraption" and sounded awesome! It quickly became the industry standard in the 70's. AM solid state also came out with real positive peak capability.....decent AM audio performance was in reach!
It needed to be tweaked every year or so....once you knew the routine it was easy to keep it sounding good. The clipper was very "soft" and was not very good....same for the assymmetry circuit. There were a million replacement clipper boards for the DAP....practically everyone built one.
You had to keep an eraser for the circuit board edge connectors......
I still know of a station, owned by an old engineer, who uses a DAP. In his rack is a brand new 9200. He swears the DAP sounds better....
 
> Go to your friendly garden store and buy a nice flowering
> tree.
>
> Dig a large hole.
>
> Put the DAP in the bottom.
>
> Then the tree's root ball on top of the DAP.
>
> Add dirt. ;-)
>

God no! The DAP was a great processor and today, tweaked with the right airchain, can sound great on AM. NOT a processor to "give away" if it still works. I think Dorrough still services them.
 
They aren't bad to as other than air chain processing. Run your phone interface through it. It does a nice job keeping the tonal quality of your phone calls consistant. I don't know if they are using one, but listen to the quality of the phone calls on the Hanity show. That nice low end on the caller sounds great!

Not bad to run a comrex through if you want your remotes to sound closer to your studio mic/mic processing.

There are uses for these. Make sure you re-cap them and make sure it's all working right.

> > > Anyone have a manual for one of these? A copy would be
> > > fine.
> > > Also, if anyone has any thoughts on these 70's vintage
> > > boxes, I'd like to hear them.
> > >
> > Go to your friendly garden store and buy a nice flowering
> > tree.
> >
> > Dig a large hole.
> >
> > Put the DAP in the bottom.
> >
> > Then the tree's root ball on top of the DAP.
> >
> > Add dirt. ;-)
> >
> No No No.....don't treat that poor littl' ol' DAP that way!
> You must not be old enough to remember when the 310 first
> came out. The world was awash in LevelDevils and Volumax's,
> with most major market stations cascading anywhere from 3 to
> 10 units with progressively faster attack/release times.
> Usually drug the audio across a couple of diodes after that,
> followed by a crude RC filter. But then, half the AM
> stations in the USA couldn't modulate positives above 70%,
> so who noticed.
> The times were cool but the waves were square!!
> The DAP was an amazing "contraption" and sounded awesome! It
> quickly became the industry standard in the 70's. AM solid
> state also came out with real positive peak
> capability.....decent AM audio performance was in reach!
> It needed to be tweaked every year or so....once you knew
> the routine it was easy to keep it sounding good. The
> clipper was very "soft" and was not very good....same for
> the assymmetry circuit. There were a million replacement
> clipper boards for the DAP....practically everyone built
> one.
> You had to keep an eraser for the circuit board edge
> connectors......
> I still know of a station, owned by an old engineer, who
> uses a DAP. In his rack is a brand new 9200. He swears the
> DAP sounds better....
>
 
I have a manual. I'd be glad to run off a copy and send it to you if you still need one. Just tell me where to send it.

Allen


> Anyone have a manual for one of these? A copy would be
> fine.
> Also, if anyone has any thoughts on these 70's vintage
> boxes, I'd like to hear them.
>
<P ID="signature">______________
Consolidated Corporate Radio S U C K S !!!!!!</P>
 
Comment for Steve re: DAP 310. I know something about them. The DAP 310 is an FM tri-band limiter and uses a clipper for overmodulation peak control. It can be used for AM but back the signal down from the clipper and follow the unit with a good dynamic peak limiter. You might be able to pull the limiter board and replace it with the limiter board from an AM dap limiter. Something to check out. It is a good sounding limiter if used properly. We had one at a station at which I was the engineer. I backed off the clipper and followed it with another good quality FET limiter. The station sounded great.

For you guys in the peanut gallery, whats all that crap about corporate #%*& __? Any station corporate owned or not needs a good limiter to keep the modulation under control or it will sound like crap! The DAP is about as good as any, although some of the new state of the art stuff is considerably better. But I'll take a DAP 310 any day.

Jackson326
 
Take the book, get it going properly, and you'll be impressed. It's still a good box... whan it was introduced, it was a phenominal box. It was one of the first commercial multiband processors. There is almost as much lore floating around about hotrodding the DAP as there is for the Volumax/Audimax chain. As ar as I know, Mike Dorrough is still around making Loudness meters. You might give him a call and ask about the DAP. Back in the days of Katz Broadcasting (Katz - The Best) he spoke to the engioneers assembled over dinner at an NAB show. Very impressive gentleman. Check his website.
 
I used to repair and calibrate them and still have some spare parts. (Don't ask for meter bezels. They're not to be found.)

The problem with many units today is that they have been modified. I have one in my work room from which some person removed the expander cards. Some units I saw had the FETs replaced. Unfortunately, the units were very particular about their FETs. Some parts with exactly the same number (J112?) would not work correctly. God knows how many people modified the equalizer cards.

There was a power supply modification that replaced a zener diode with an LM342 regulator. The mod helped to improve the stability and drift.

Tuned up and left alone, the Dorrough 310 was a wonderful box. Many people wanted to know my secret for AM audio processing. When I told them the truth (a very clean audio chain and a single box -- the 310), they often didn't believe me.

Mike and Kaye Dorrough are two of the finest people you will ever meet. They are honest, ethical, and caring business people. It is unfortunate that we have not been in touch for quite a few years.
 
The DAP 310 was a killer box for the time and can still be a nice thing on a station. I wanted to pick up a few for the high school radio station I'm building but they don't have a ton of budget, so I've been using what I can get donated to the district. I had a 310 in of one of the school's TV studios and it sounded great. The sad thing was when I went to reclaim the gear at the old abandoned studio the 310 was nowhere to be found - I suppose the former A/V guy had other ideas for it.

I just sent some loudness meters back to Dorrough for repair and recently got them back. Mike is enjoying retirement, but Kay is still involved with the day to day business. They seem to be pretty busy, which I'm glad - they make a great product and I love those meters.

Out of all the things I still have squirreled away, I have this card which you plug into the left most slot when looking at the front panel on a 310 (after removing the dummy card). Made by a third party, it was a pink noise generator that could be left inside and switched on to do the alignment of the 310. Neat little card. I think it kept it always hoping I could find a few 310's to use it in. The hard thing to find seems to be units with the AM Limiter cards, as it seems I've always seen the ones that were used on FM.
 
Mike Phillips said:
Mike and Kaye Dorrough are two of the finest people you will ever meet. They are honest, ethical, and caring business people. It is unfortunate that we have not been in touch for quite a few years.
Click to expand...

Probably some of the truest and sincere words spoken on this forum in years.

I met Mike when he was selling DAPs out of the trunk of his car. Best investment I made at a small market station was getting one of his units.
 
Go to your friendly garden store and buy a nice flowering tree.

Dig a large hole.

Put the DAP in the bottom.

Then the tree's root ball on top of the DAP.

Add dirt. ;-)
Click to expand...
Nice try, really, take your old DAP, pack it in a nice box ............. I'll send you my FedEx number.

Best box on the planet in it's day, made me alot of money, and made me sound gooood.
 
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