Subwoofer - Going to external amplification

[haraldo]

Plate amps for subwoofers are bears, I am having tons of issues and thinking to just rip out the amps and go with external amplification. The Audio Physic Rhea II is excellent subwoofers but there is too much of known issues with the plate amps and Chinese built amplifiers willingly breaking. I am having 4 subs so, external amps for all of them

So here we go my friends

Has anyone here done anything with Labgruppen? experiences?

I'm thinking specifically of PDX3000 or PD3000
The difference between these two is that the PDX3000 has various DSP controls, while the PD3000 does not

These seem to be pretty hefty, more than enough power for my needs; seem to be well built solid pro-class d amplifiers, and Labgruppen semmingly have rock-solid reputation for being unbreakable ....

So: Use Case is external amplifiers for subwoofers = knocking out troubled plate amplifiers and running external amplification

Input anyonw?

 

[lovinthehd]

I remember several diy sub guys posted about the chinese labgruppen clones to save money, but not too many used the actual thing that I remember. I just looked at pricing on this model, much more reasonable now than the last time I looked. I've seen some snark since Behringer / Music Tribe took it over. You might want to check for fan noise, tho. DSP may be nice to have if the original amp was customized with such. If you do remove the plate amp, how/what will you fill the void with? I'd just figure out a way to connect the external amp with it in place....

 

[TLS Guy]

Plate amps for subwoofers are bears, I am having tons of issues and thinking to just rip out the amps and go with external amplification. The Audio Physic Rhea II is excellent subwoofers but there is too much of known issues with the plate amps and Chinese built amplifiers willingly breaking. I am having 4 subs so, external amps for all of them

So here we go my friends

Has anyone here done anything with Labgruppen? experiences?

I'm thinking specifically of PDX3000 or PD3000
The difference between these two is that the PDX3000 has various DSP controls, while the PD3000 does not

These seem to be pretty hefty, more than enough power for my needs; seem to be well built solid pro-class d amplifiers, and Labgruppen semmingly have rock-solid reputation for being unbreakable ....

So: Use Case is external amplifiers for subwoofers = knocking out troubled plate amplifiers and running external amplification

Input anyonw?

View attachment 64768

That looks like a sealed sub. If that is the case it will need EQ below the native F3 and a high pass at driver xmax to prevent driver damage.
So you will need an accurate model of that driver in that box.

If it is a ported sub then it is a straightforward proposition, but not if it is a sealed sub. So if you get an external amp, then you need an amp and equalizer.

There are plate amps with equalizers for DIY sealed subs, which might be a solution. You might be further ahead buying new subs though. May be one Arendal could replace all your subs and you would be further ahead. They are in your part of the world.

 

[TLS Guy]

Plate amps for subwoofers are bears, I am having tons of issues and thinking to just rip out the amps and go with external amplification. The Audio Physic Rhea II is excellent subwoofers but there is too much of known issues with the plate amps and Chinese built amplifiers willingly breaking. I am having 4 subs so, external amps for all of them

So here we go my friends

Has anyone here done anything with Labgruppen? experiences?

I'm thinking specifically of PDX3000 or PD3000
The difference between these two is that the PDX3000 has various DSP controls, while the PD3000 does not

These seem to be pretty hefty, more than enough power for my needs; seem to be well built solid pro-class d amplifiers, and Labgruppen semmingly have rock-solid reputation for being unbreakable ....

So: Use Case is external amplifiers for subwoofers = knocking out troubled plate amplifiers and running external amplification

Input anyonw?

View attachment 64768

I have searched for specs and the design of that unit and come up empty. In the instruction manual there are zero specs. I can find no meaningful specs and no mention of the design. I did find reports of people servicing the unit on the DIY forum, as failures seem to be their hallmark. As you mentioned poor quality Chinese construction is mentioned by those who have worked on it.

One impression I have formed, is that these units are grossly overpriced.

I note that the units are German, which is another red flag. In the audio arena Germans have distinguished themselves for producing some of the worst speakers on the planet over the years.

So, unless I see evidence to the contrary, those units are not worth a cent of further investment, but in need of deep sixing.

 

[haraldo]

Germans have distinguished themselves for producing some of the worst speakers on the planet over the years.

Thanks for your input

The Rhea II is with a driver on each side, active / passive .....

I strongly suggest the bad speaker situation is not the case for Joachim Gerhard designs, these are extremely well designed products, also the subwoofers, where as the Audio Physic Minos ranks really high, for my use case the Rhea II is excellent, with a very solid build quality of the cabinet, well performing drivers, but hampered by troubled amplifiers....

Coupled with Trinnov Amethyst and, the sub integration is really great, and with 4 subwoofers I suffer no audible limitations and / or compressions, I cannot go crazy as I live in a flat, there are neigbors.

Arendal is definitely on the radar, and there are other options too ....
Honest I believe Arendal could be step down from the Audio Physic, there is sold tons of them here because these are really well performing subs.... but some parts breaking in the amps....

 

[AcuDefTechGuy]

Plate amps for subwoofers are bears, I am having tons of issues and thinking to just rip out the amps and go with external amplification. The Audio Physic Rhea II is excellent subwoofers but there is too much of known issues with the plate amps and Chinese built amplifiers willingly breaking. I am having 4 subs so, external amps for all of them

Yeah, I’ve been against putting anything (amps/EQ) inside subs and speakers for 30 years because of this. I’ve seen $5-8K subs with internal plate amps dying after a few months to a few years.

The 1st sub I’ve ever owned as a kid used external amp, and all 12 subs I own now use external amps.

 

[haraldo]

I remember several diy sub guys posted about the chinese labgruppen clones to save money, but not too many used the actual thing that I remember. I just looked at pricing on this model, much more reasonable now than the last time I looked. I've seen some snark since Behringer / Music Tribe took it over. You might want to check for fan noise, tho. DSP may be nice to have if the original amp was customized with such. If you do remove the plate amp, how/what will you fill the void with? I'd just figure out a way to connect the external amp with it in place....

Thx ..... there is no hole, as there is a fully closed cutout for the plate amp, I would just need to replace with a fiber or aluminium plate to make it flush. Fan noise is a concern yes...... THX
I do have a Trinnov with crazy DSP capabilities, but still possibly the DSP variant of the amp as it is only slightly more expensive. Output capabilities is zero concern here, Norwegian flat, not that large and I cannot go crazy loud with neighbors.

These subs are so good that I am confident of a very nice price/value proposition when replacing amps
I also heard with the guys over here selling those things (very capable people) thinking it will be really worthwhile thing to do.

 

[haraldo]

Work in progress, all German speakers, Audio Physic Avanti III speakers is a piece of art with performance, 4 Audio Physic Rhea II subs bought second hand at "steal prices". Many people want newer subs that are not performing better.

Trying to get "ultra-clean" look, as much towards ZEN style as I can get with this equipment
I just (almost) finished that acoustics wall, there is 50mm rockfon behind the front pane....
That opened space below TV will be closed too with the same oak finish
diy bass traps, left one to be extended to ceiling
All speakers and subs spiked to slate stone plates
Cables hidden in cables gates within the acoustic wall
Extremely wide speaker positioning works well here

 

[TLS Guy]

Thanks for your input

The Rhea II is with a driver on each side, active / passive .....

I strongly suggest the bad speaker situation is not the case for Joachim Gerhard designs, these are extremely well designed products, also the subwoofers, where as the Audio Physic Minos ranks really high, for my use case the Rhea II is excellent, with a very solid build quality of the cabinet, well performing drivers, but hampered by troubled amplifiers....

Coupled with Trinnov Amethyst and, the sub integration is really great, and with 4 subwoofers I suffer no audible limitations and / or compressions, I cannot go crazy as I live in a flat, there are neigbors.

Arendal is definitely on the radar, and there are other options too ....
Honest I believe Arendal could be step down from the Audio Physic, there is sold tons of them here because these are really well performing subs.... but some parts breaking in the amps....

So you are saying this is a passive radiator design, with a passive radiator in place of the port. So this acts basically like a ported enclosure, but the roll off below F3 is 36 db per octave versus 24 db per octave for a port. A passive radiator is used when a port will not fit in the box.

So this sub will not have Eq, though it may be high passed above F3. Unfortunately there is no useful information on these units on the NET. No meaningful specs were ever published, which is a red flag to me. I highly doubt the Arendal subs would be step down. If those subs are as good as you say, they would have posted bragging rights so everyone could see and recommend them. I certainly could not give them any seal of approval, or give them a recommendation. The absence of meaningful specifications would lead me the steer people away from them.

But yes, you could use an external amp, and if you noted excessive excursion of the driver or passive radiator, you would need to high pass, but I can't tell you at what frequency.

 

[haraldo]

So you are saying this is a passive radiator design, with a passive radiator in place of the port. So this acts basically like a ported enclosure, but the roll off below F3 is 36 db per octave versus 24 db per octave for a port. A passive radiator is used when a port will not fit in the box.

So this sub will not have Eq, though it may be high passed above F3. Unfortunately there is no useful information on these units on the NET. No meaningful specs were ever published, which is a red flag to me. I highly doubt the Arendal subs would be step down. If those subs are as good as you say, they would have posted bragging rights so everyone could see and recommend them. I certainly could not give them any seal of approval, or give them a recommendation. The absence of meaningful specifications would lead me the steer people away from them.

But yes, you could use an external amp, and if you noted excessive excursion of the driver or passive radiator, you would need to high pass, but I can't tell you at what frequency.

Which world you live in? The early Audio Physic products are amongst the most praised and well rewarded products anywhere, Audio Physic are speakers that changed the world .... The guy who designed these subwoofers is one of the most respected loudspeaker designers in Europe ..... over more than 4 decades

Are you trying to help or merely being a pure annoyance?
Have you become an expert about a product that you know nothing about and that you never seen or heard?

I spent 30+ years seriously auditioning hi-end audio gear and do have a very good sense of what works and what does not work.... you seem to think I am some sort of complete idiot?

They don´t need to do bragging, everyone who hears his products know what we are talking about, I seen these subs coupled to $300.000+ rig, where the subwoofers may not be the weak link

You are 100% derailing the thread
Sorry but you are really not discussing anything about what I asked about in this thread. I am not asking about advice about subwoofers to buy

(you are 2 clicks away from being permanently blocked)

 

[TLS Guy]

Which world you live in? The early Audio Physic products are amongst the most praised and well rewarded products anywhere, Audio Physic are speakers that changed the world .... The guy who designed these subwoofers is one of the most respected loudspeaker designers in Europe ..... over more than 4 decades

Are you trying to help or merely being a pure annoyance?
Have you become an expert about a product that you know nothing about and that you never seen or heard?

I spent 30+ years seriously auditioning hi-end audio gear and do have a very good sense of what works and what does not work.... you seem to think I am some sort of complete idiot?

They don´t need to do bragging, everyone who hears his products know what we are talking about, I seen these subs coupled to $300.000+ rig, where the subwoofers may not be the weak link

You are 100% derailing the thread
Sorry but you are really not discussing anything about what I asked about in this thread. I am not asking about advice about subwoofers to buy

(you are 2 clicks away from being permanently blocked)

I am just trying to help you. However I am severely handicapped as this chap you are bragging up, posted no meaningful data about the product and design. There are no useful measurements at all, not even 3 db points.

So, in the absence of data I can't advise with any precision on how to proceed.

All I can say, is that when I see a product like that, alarm bells and snake oil alerts ring loudly in my head.

Your testimony is fine as far as it goes, but it does not help me one bit in advising you how to salvage your speakers.

What I found out on a DIY repair forum made me doubly cautious.

Maybe you have some solid data you can post here? An anecdotal opinion does not help me at all. I need the hard facts which I can't find. If there is good data other then audiophool subjective data, then I am ready to receiver it, and modify my opinion and also be able to give you solid advice on how to proceed. I will be only too happy to proceed on that basis.

 

[Alex2507]

Throw those subs straight in the rubbish.

What is your budget for new subs?

They’re not cheap, you know.

 

[haraldo]

Throw those subs straight in the rubbish.

What is your budget for new subs?

They’re not cheap, you know.

If I should do then it would be for Perlisten, like D212S, or build myself.... but I don't have budget to replace now!

 

[TLS Guy]

If I should do then it would be for Perlisten, like D212S, or build myself.... but I don't have budget to replace now!

May be the subs are salvageable? Can you post more accurate technical data about them, other than the meagre amount published on the Net? One other option is to buy the Dayton Woofer test system from Parts Xpress. That would provide enough date to salvage those subs most likely.