Digital Amp mojo....

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Kevin P

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Digital Amp mojo....
« on: 23 Oct 2004, 12:44 am »
Ok... round two.  

Here is the latest and greatest digital amp kit.  We have teamed up with Adire who imports the Hypex gear in North America and we are going to offer the Hypex UcD 180 in kit form with our Exodus Chassis.  

Price for a complete two-channel kit should be in the $500 range.   I've been testing this guy since RMAF and it seems to be rock solid.   Not a noise, hiss or zip during fire-up or shut down.   The protection circuit works without a hitch and I've yet to be able to blow one even when trying.   :o    The gain is a more traditional 26db and it has a 10K input impedance.  



http://www.hypex.nl"target="_blank">http://www.diycable.com/main/images/inside.jpg"hspace="3" vspace="3" border="0">

Harmon

Digital Amp
« Reply #1 on: 23 Oct 2004, 12:59 am »
I am not an engineer but it seems there is not much soldering to be done.

Kevin P

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Digital Amp mojo....
« Reply #2 on: 23 Oct 2004, 02:38 pm »
There will be some soldering required but not on the PCB.   All the connectors are slip-on so there is no worries about damaging sensitive surface mount devices on the board.

The soldering points are at the power supply caps, speaker binding post & the RCA inputs.    None of these parts are heat sensitive so as a beginner you don't have to worry about damaging them.

Dmason

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Digital Amp mojo....
« Reply #3 on: 23 Oct 2004, 04:29 pm »
Fine looking workmanship Kevin, have you done this before? :lol:

Perhaps you could describe what you hear with the Hypex design. Inquiring minds wish to know.

Kevin P

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Digital Amp mojo....
« Reply #4 on: 23 Oct 2004, 04:46 pm »
Yes... I've been down this road before but I'm not laughing.  :roll:

Inquiring minds are going to have to keep inquiring.   I'm not going to comment about subjetive things because I sell it and it is entirely too easy to cross the line of stretching the truth when you have a financial interest involved.

I'm sure someone will step-up to the plate and build an amp and then they can comment about subjective things.

guest1632

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Digital Amp mojo....
« Reply #5 on: 27 Oct 2004, 06:36 am »
Quote from: Kevin P
Yes... I've been down this road before but I'm not laughing.  :roll:

Inquiring minds are going to have to keep inquiring.   I'm not going to comment about subjetive things because I sell it and it is entirely too easy to cross the line of stretching the truth when you have a financial interest involved.

I'm sure someone will step-up to the plate and build an amp and then they can comment about subjective things.

Kevin P

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Digital Amp mojo....
« Reply #6 on: 27 Oct 2004, 02:05 pm »
Ray,

There are some sensitive issues I'm crossing here....

I'd prefer to stay out of it for the moment and I don't have enough listening time with the Hypex amps to venture a comment yet.

Grover

Digital Amp mojo....
« Reply #7 on: 27 Oct 2004, 04:14 pm »
Kevin:

What's the power rating for the amp and is there any problem with 4 ohm speakers?

I've got the Basie preamp - do you have an opinion or any listening tests on how well this tube pre might mate with the digital amp?

Thanks

Kevin P

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Digital Amp mojo....
« Reply #8 on: 27 Oct 2004, 04:43 pm »
There is zero problems with 4 Ohm loads.   The input impedance is 10K which is lower than most tube amps but it doesn't present a problem with the Basie.

The gain of the amp is probably just about perfect for most active line stages.

guest1632

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Digital Amp mojo....
« Reply #9 on: 28 Oct 2004, 12:39 am »
Quote from: Kevin P
Ray,

There are some sensitive issues I'm crossing here....

I'd prefer to stay out of it for the moment and I don't have enough listening time with the Hypex amps to venture a comment yet.

Kevin P

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Digital Amp mojo....
« Reply #10 on: 28 Oct 2004, 01:32 pm »
Ray,

We have two projects involving amplifiers that we are working on.

#1.   Digital amps using the Hypex Modules.   These should be available soon as all parts are on the way.   We have some diagrams and instructions to finish but these are on fast track and the Hypex based complete amplifier should be available within the next 3 weeks.

#2.   An LM4780 based amplifier (often called a gainclone or chipamp) which uses a similiar chassis as the digital amp.   These will be available before the end of the year if all goes well but there are many more things we have to source before the kits officially become available.  

The LM4780 based amps are going to be our value line amplifiers with a complete 2-channel amplifier package coming in around $300 complete.    All of our amplifiers will be very flexible in design.  Options for multichannel, integrated and other features will make them very modular for the DIYer.   They will not look like kits when finished as we have sourced VERY high quality chassis and parts.

Harmon

Amp Kits
« Reply #11 on: 27 Nov 2004, 03:03 am »
What are the specifications of the Hypex and the LM4780 kits?

Kevin P

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Digital Amp mojo....
« Reply #12 on: 27 Nov 2004, 02:28 pm »
Sure... the information on the Hypex stuff is best found at the Hypex site.  The quick & dirty is that the base module is 120W @ 8Ohms & 180W @ 4 Ohms.    They have a new module that is 200W @ 8 Ohms but they are short on supply at the moment.

www.hypex.nl

The information on the LM4780 is best found direct from National Semiconductor's tech notes on the device.   The version we have designed isn't too far from the National Semiconductor tech notes so all the measurements and specs should just about match up with the measurements they have listed.  The quick & dirty is 60W @ 8 Ohms stereo or bridge the modules for 120W.

www.national.com

Then do a search for "4780"

guest1632

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Digital Amp mojo....
« Reply #13 on: 27 Nov 2004, 02:33 pm »
Quote from: Kevin P
Sure... the information on the Hypex stuff is best found at the Hypex site.  The quick & dirty is that the base module is 120W @ 8Ohms & 180W @ 4 Ohms.    They have a new module that is 200W @ 8 Ohms but they are short on supply at the moment.

www.hypex.nl

The information on the LM4780 is best found direct from National Semiconductor's tech notes on the device.   The version we have designed isn't too far from the National Semiconductor tech notes so all the measurements and specs should just about ma ...

Kevin P

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Digital Amp mojo....
« Reply #14 on: 27 Nov 2004, 06:45 pm »
Just waiting on Hypex to deliver modules at this point.   Once we have more modules we will be working on instructions and then they will go on the site.

The LC Audio units just didn't work out for us.

MarinRider

Digital Amp mojo....
« Reply #15 on: 28 Nov 2004, 07:56 pm »
What sort of grounding scheme is used in the amp in the picture?

JLM

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Digital Amp mojo....
« Reply #16 on: 28 Nov 2004, 08:41 pm »
Kevin,

How much for the digital kit?

How big are the transformers on each?

How much to assemble each?

Would assembled amps include a warrantee?

$300 for the 60 wpc chip amp seems very reasonable if everything is included.

thanks

Kevin P

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Digital Amp mojo....
« Reply #17 on: 29 Nov 2004, 02:11 pm »
Quote from: MarinRider
What sort of grounding scheme is used in the amp in the picture?


The amp PS is floating from the chassis ground on this one.   Other than that it is the same PS as shown on the Hypex documentation notes.  

I'd experiment with running a ground from between the 10,000uF caps to the chassis ground but you can often introduce noise from the safety ground.  Floating it is dead quite and the chassis is still safety grounded via the IEC ground.

Kevin P

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Digital Amp mojo....
« Reply #18 on: 29 Nov 2004, 02:45 pm »
Quote from: JLM
Kevin,

How much for the digital kit?



Don't know yet..... should be in the $500-$600 range but Hypex is changing prices by swapping an opamp on the input an the exchange rate is not exactly favorable at the moment so I'm not sure exactly where the price will land.

Quote from: JLM

How big are the transformers on each?


In the UCD 180 version shown uses 250VA transformer.   It only needs about 100VA per channel.   The UCD400 will use a 500VA transformer.   Both 250VA & 500VA are more than enough if you use a quality transformer.  

Quote from: JLM

How much to assemble each?


They are a kit.  All of them will be kits as I'm not getting into the finished amplifier business.  We will continue to focus on very easy to build kits that introduce more people to the joy of DIY.

It isn't real labor intensive so figure 3-6 hours depending on how fast you work, tools available & experience.





Quote from: JLM

Would assembled amps include a warrantee?


The kits come with a parts warrantee just like all of our kits.  
 
Quote from: JLM

$300 for the 60 wpc chip amp seems very reasonable if everything is included.


It is very reasonable as my parts cost on just the amplifier chassis, Cardas inputs & speaker post etc... is about half that amount.  The goal is to have one inexpensive entry level unit to get new people involved in DIY.   I think Doc B has done a great job of introducing new people to kit building by offering the Foreplay at such a low price that people are willing to take the leap of faith and build it because they are not out much money if it goes bad.    Same idea with the $300 LM4780 amplifier.   For $300 I'm hoping a lot of people will take the leap and build their first project.