Real opinions on Coldamp - Page 3 - diyAudio
Go Back   Home > Forums > Amplifiers > Class D

Class D Switching Power Amplifiers and Power D/A conversion

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 6th February 2008, 11:05 PM   #21
diyAudio Member
 
Join Date: Aug 2004
Location: Uppsala,Sweden
Ian ,
last summer I made some "research" about high quality PA amps.
The ones I found most interesting was from this German Manufacturer. POWERSOFT DIGAM.
They seems to have a good reputation for very good quality of sound and of reliability as well. Expensive as a new item but maybe a used one? The K-10 is capable of 2x4000W (which ones?) into 4 ohms or 6000 W into 2 ohms and weighs
12 kg. Bridge them for 12000W into 4 ohms. Nice....Definitely Class D and SMPS. Some knowledge has gone into them I think.

There are some models to choose from and sorry I have not found any English version for the text...

http://www.thomann.de/de/powersoft_digam_k10.htm

Swedish, but there is a picture of a K-amp without the lid:
http://www.crafton.se/crafton/pdf/we...owersoft06.pdf
__________________
Without wonderment,no life.
  Reply With Quote
Old 7th February 2008, 01:55 AM   #22
diyAudio Member
 
Join Date: Jul 2004
Location: Seattle USA
Quote:
Originally posted by The golden mean
Here we go again. Lightweight amplification isnīt too hard to find these days!

Mackie FRS series:

http://www.mackie.com/products/frsseries/splash.html
Mackie FRS aren't class-d, the lower power ones are class-ab and higher are class-h. With SMPS. Why not class-d? They don't know how to make them yet.

Now these look interesting:
http://vestax.com/v/products/active/vda1000.html
switchable power output setting and any kind of input you can think of.
Street price seems to be $550 US
  Reply With Quote
Old 7th February 2008, 09:02 AM   #23
iand is offline iand  United Kingdom
diyAudio Member
 
Join Date: Feb 2007
Location: London
Quote:
Originally posted by The golden mean
Ian ,
last summer I made some "research" about high quality PA amps.
The ones I found most interesting was from this German Manufacturer. POWERSOFT DIGAM.
They seems to have a good reputation for very good quality of sound and of reliability as well. Expensive as a new item but maybe a used one? The K-10 is capable of 2x4000W (which ones?) into 4 ohms or 6000 W into 2 ohms and weighs
12 kg. Bridge them for 12000W into 4 ohms. Nice....Definitely Class D and SMPS. Some knowledge has gone into them I think.

There are some models to choose from and sorry I have not found any English version for the text...

http://www.thomann.de/de/powersoft_digam_k10.htm

Swedish, but there is a picture of a K-amp without the lid:
http://www.crafton.se/crafton/pdf/we...owersoft06.pdf
I've been following Powersoft's progress for several years, and they have some extremely impressive stuff (the K20 is 20,000W with PFC in 1U!!!) at equally impressive prices (7000 euros for the K20) -- though when you write that as 350euros/kW it looks positively cheap :-)

Their Digimod3000PFC would be ideal if they'd sell them to me... :-(

Ian
  Reply With Quote
Old 7th February 2008, 03:47 PM   #24
diyAudio Member
 
Join Date: Aug 2004
Location: Uppsala,Sweden
Thereīs a lot of stuff on this German site about the differences between certain PA amps.
http://www.paforum.de/phpBB/viewtopi...r=asc&start=30

Sorry, I read German so and so and is not prepared to translate the extensive text to English, but what is indeed interesting is that people have compared amps in a live context.

They evaluate bass performance for instance, and while the conclusions may be subjective I prefer this to no evaluation at all!

For my part I seek a replacement for the $ 10.000 amp I use for the bass drivers. Iīm going to triamp so the expensive amp may do its duty in mid frequencies territory(Accuton C 200 and 2x C79 per channel). I donīt care so much about weight. The Class A amp weighs 100 lbs and the current bass amp 60 lbs. Speakers will weigh about 400 lbs/ each if they ever will be finished.

By no means a PA-system!
__________________
Without wonderment,no life.
  Reply With Quote
Old 7th February 2008, 08:03 PM   #25
diyAudio Member
 
Join Date: Aug 2004
Location: Uppsala,Sweden
For use with subs I think the (unfortunately discontinued) Crown K2 is hard to beat. Bridge them and you get 2500 W from each . Sorry they arenīt the most lightweight at about 38 pounds.
No fan but may pollute the mains to some extent....

http://home.earthlink.net/~mixthat/par/crownk2.html

A bit frustrating that you can buy them second hand in the US for about $ 600-700 or new for twice of that.

I saw a used one at www.audiomarkt.de for 1800 Euro. A bit too much I think.
__________________
Without wonderment,no life.
  Reply With Quote
Old 7th February 2008, 09:31 PM   #26
diyAudio Member
 
Join Date: Jul 2004
Location: Mountain View, CA
Not pro, but Wyred4sound and D-sonic sell multichannel amps using the ICE 1000ASP modules.

http://www.wyred4sound.com/ICE_CUBE_...TICHANNEL.html

http://www.d-sonic.net/
__________________
-----------------------------------------
Noah
  Reply With Quote
Old 8th February 2008, 11:25 AM   #27
diyAudio Member
 
Join Date: Feb 2006
Location: east coast
Default Returning to the subject of the thread...

I have used the Coldamp SPS80 in an implementation of the UcD400HG's. They were powered by the Hypex 1KVA toroid and the Hypex HG power supply before I moved them to a new case and installed the SPS80.

I have had no trouble at all with the Coldamp product, it works and sounds great. I don't hear any difference between it and the linear supply. The weight, part count reduction, wiring simplicity, and foot-print savings alone were worth the replacement.

I wasn't too thrilled that I had to alter it (minor soldering) to accomodate my US 110 mains voltage but it was easy and I guess not worth the time for Coldamp to manufacture a version based on such a minor change to what is already a DIY product.

In short, and to the point, in my personal experience their product works as advertised and their service was good. I would use them again without hesitation.

Regards,
Tom
  Reply With Quote
Old 8th February 2008, 10:32 PM   #28
iand is offline iand  United Kingdom
diyAudio Member
 
Join Date: Feb 2007
Location: London
Thanks everyone -- it seems like the main issue with Coldamp is related to how they were educated in the art of class-D rather than any problem with the products.

Ian
  Reply With Quote
Old 9th February 2008, 12:51 AM   #29
Eva is offline Eva  Spain
diyAudio Member
 
Eva's Avatar
 
Join Date: Oct 2003
Location: Near the sea
Send a message via MSN to Eva
Be very careful with SPS80 because at least the first batch of them were unsafe in terms of mains isolation and would not pass any safety agency approval. This was because the designer didn't allow proper PCB spacing between primary and secondary sides and he did choose an unsafe way to mount the primary side switching transistors to the heatsink. Some customer complained about a ticking noise too, which is a sign of bad control loop design. A switching mode power supply may be malfunctioning and unreliable in several ways and still not burst in smoke within a reasonable period of time.

The main problem is not how a designer gathers the knowledge, it's the fact that it's completely unfair to advertise and sell your very first prototypes as if they were state-of-the-art class D and SMPS, when they are full of hidden pitfallas that you don't know how to solve or don't know about at all because you have still a lot to learn.


Coldamp is like that:

Hey, I'm selling class D modules at $150 a piece but they produce a big turn-on thump that I don't know how to remove. I will disguise myself as a naive DIYer and I will ask some helpful forum member to fix my commercial product.

Hey, I want to implement post-filter feedback in my $150 commercial class-D module but I don't have a clue about how to do it. I will disguise myself again as a naive DIYer and I will ask some experienced forum member to design a good feedback loop for me.

Hey, I don't know how to do the transformer and capacitor calculations for my commercial $300 SMPS. I will disguise myself again as a naive DIYer and I will ask some guru at DIYaudio to do the math for me.
__________________
I use to feel like the small child in The Emperor's New Clothes tale
  Reply With Quote
Old 9th February 2008, 03:40 AM   #30
diyAudio Member
 
Join Date: Feb 2006
Location: east coast
Default EVA, now you have me worried...

EVA, now you have me worried. My implementation mounts the SPS80 directly to my metal equipment chassis which is grounded to the mains.

I have been confident (up till now) that any isolation failure of the SPS80 would be handled by this chassis ground.

I am no engineer and, believe me, if you are worried then so am I! Am I missing something dangerous?

Regards,
Tom
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Coldamp Bgt Class D 67 11th April 2012 08:16 AM
New coldamp toy Pierre Class D 4 29th December 2009 02:31 PM
Whistling Coldamp SimonInd Class D 8 1st August 2007 09:31 AM


New To Site? Need Help?

All times are GMT. The time now is 12:12 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright Đ1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2