Amp recommendations for efficient speakers

[whaleboard]

Hey everyone,

I'll be building myself a pair of The-Loudspeaker-III designed by Troels Gravesen in the near future.
It's an efficient set of speakers, rated at 92db, and it requires 15W per channel. The subwoofer part is active, powered by an Hypex FA251, and fed from the crossover.

I'm looking for recommendations as to which amplifier I should get to honor these beauties, something that could pump some details out.
I'm willing to go the DIY route to get the best bang for my buck. Also willing to go through the tube route. I can also just buy something.
I'd like to keep the amp section as budget-savvy as possible, within reasons.

 

[Zek]

I think you are on the completely wrong forum.
You should have asked your question on some DIY forum.

 

[Wombat]

Use the one used in the original speaker:

https://www.oaudio.de/en/speaker-diy/hypex-fusion-plate-amps/hypex-fusionamp-fa502.html

or 2x FA 251: https://www.oaudio.de/en/by-manufacturer/hypex-electronics/hypex-fusionamp-fa251.html


This is 2-channel, more power than in OP and cheaper: https://www.oaudio.de/en/by-manufacturer/hypex-electronics/hypex-fusionamp-fa122.html


Reference: http://www.troelsgravesen.dk/The-Loudspeaker-III.htm - That is an interesting project.

http://www.troelsgravesen.dk/FUSION_FA251.htm

 

[kipman725]

Go even further and use the 3 channel hypex plate amp and ditch the passive crossover. You can also build with a flat baffle and do the time alignment in the DSP instead.

 

[ta240]

"as budget-savvy as possible, within reasons. "

Budget is a very relative term. One person's crazy expensive is another person's reasonably priced.
What is your budget range? $500, $1000, $2000, $5000+?

 

[MakeMineVinyl]

Given the efficiency, you would only need something around 50-100 watts. I like tubes, but that's just me.

 

[morpheusX]

For tweeters, what about something based on the modulus-86 with a GUARDIAN-86 for protection?

 

[avanti1960]

https://www.thetubestore.com/elekit-tu-8600s-tube-amp

 

[whaleboard]

I might go for a Tubelab SSE build with KT88s or EL34s. It's a somewhat easy DIY build with apparently great results, has its own subforum over at diyaudio. In ultralinear mode it's able to output about 14 watts.

When Troels Gravesen states that the MT part needs at least 15 watts, does he mean to achieve very high volume levels?
I'm afraid of building this neat little tube amp to realize that it's not able to drive my speakers.
I'm having a hard time figuring out how watt per channel influences dynamics and sound levels. I'm not looking to blast my ears off with these speakers, at all.

 

[MakeMineVinyl]

The 92dB for 1 watt efficiency of the speakers you are intending to purchase means that when fed 1 watt, that's the sound pressure level you will get, but keep in mind that that specification is taken at something like 1m distance, so if you have a very large room, this will influence what you get. Still, I would think that if you don't plan on blasting bass heavy music, 15 watts would be fine. At any rate, tubes don't clip as harshly as transistors so a tube amp will be able to go subjectively 'louder' than a solid state one before distortion becomes noticeable.

 

[whaleboard]

The 92dB for 1 watt efficiency of the speakers you are intending to purchase means that when fed 1 watt, that's the sound pressure level you will get, but keep in mind that that specification is taken at something like 1m distance, so if you have a very large room, this will influence what you get. Still, I would think that if you don't plan on blasting bass heavy music, 15 watts would be fine. At any rate, tubes don't clip as harshly as transistors so a tube amp will be able to go subjectively 'louder' than a solid state one before distortion becomes noticeable.

Thanks, that makes it a lot clearer.
So, for bass heavy music played at a *reasonable* level, an amp with about 15 watts should do the trick with these?

The role of the Hypex here is to pick up the signal from the crossover and amplify it, right? So all the amp has to do is output a clean bass, and I'll be able to tweak it with the Hypex?

 

[MakeMineVinyl]

Thanks, that makes it a lot clearer.
So, for bass heavy music played at a *reasonable* level, an amp with about 15 watts should do the trick with these?

The role of the Hypex here is to pick up the signal from the crossover and amplify it, right? So all the amp has to do is output a clean bass, and I'll be able to tweak it with the Hypex?

I don't quite follow you about the Hypex. What I was assuming is that you were going to make a speaker system with a conventional passive crossover network. In that case 15 watts I think would be fine. Keep in mind that the majority of power is needed in the bass. Depending on your music choices and levels you listen at, the required wattage could easily go into 100s of watts.

 

[whaleboard]

The speakers I'm building uses an Hypex plate-amp (FA251) which receives its signal from the passive crossover. It amplifies the bass signal, basically. The maker of the speakers says the 15W are only required for the MT section.

What I understand is that the Hypex picks up a low-level signal from the crossover fed by the amp, and amplifies it while allowing for DSP and EQ.

What I have trouble understanding is, would the Hypex be capable of picking up a low bass signal and amplifying it without distortion? I'm new to all this.

 

[MakeMineVinyl]

In that case, the Hypex amp is receiving a filtered version of the audio which includes only the low frequencies. The burden of reproducing those frequencies is therefore relieved from the amplifier powering the rest of the speaker system (that amplifier only sees frequencies above the bass region by the filtering action of the crossover). In that case, 15 watts would be more than enough.

 

[whaleboard]

In that case, the Hypex amp is receiving a filtered version of the audio which includes only the low frequencies. The burden of reproducing those frequencies is therefore relieved from the amplifier powering the rest of the speaker system (that amplifier only sees frequencies above the bass region by the filtering action of the crossover). In that case, 15 watts would be more than enough.

I read through the whole Hypex manual and you made it clear in a second. Thanks.

But if the amp powering the speakers is not a good performer in the bass region, will it influence the Hypex bass quality?

 

[MakeMineVinyl]

I read through the whole Hypex manual and you made it clear in a second. Thanks.

But if the amp powering the speakers is not a good performer in the bass region, will it influence the Hypex bass quality?

The amplifier won't have to produce current, which translates into watts in the bass region. You should be able to adjust the amount of bass you want with the gain control of the Hypex amplifier independently from everything else.

Just be sure though that whatever crossover you are using does in fact filter out the bass going to the upper frequency amplifier!

 

[whaleboard]

The amplifier won't have to produce current, which translates into watts in the bass region. You should be able to adjust the amount of bass you want with the gain control of the Hypex amplifier independently from everything else.

Just be sure though that whatever crossover you are using does in fact filter out the bass going to the upper frequency amplifier!

I think I understand what you mean but my question is: let's *imagine* the tube amp powering my speakers has nothing below 100Hz. Logically, the Hypex would not receive any signal, thus, won't produce any bass by itself, correct?

I'm asking because getting a SE tube amp to produce low frequencies means shelling out at least 500euros on great output transformers. If I don't need my tube amp to go that low – that is if the Hypex works on its own – then I can get good, but less expensive output transformers.

Am I making sense?

 

[MakeMineVinyl]

I think I understand what you mean but my question is: let's *imagine* the tube amp powering my speakers has nothing below 100Hz. Logically, the Hypex would not receive any signal, thus, won't produce any bass by itself, correct?

I'm asking because getting a SE tube amp to produce low frequencies means shelling out at least 500euros on great output transformers. If I don't need my tube amp to go that low – that is if the Hypex works on its own – then I can get good, but less expensive output transformers.

Am I making sense?

Any remotely decent tube amp is going to extend well below 100Hz - if the one you're considering doesn't have any response at all below that frequency, look elsewhere. The tube amp output transformers won't be required to supply current below the frequency where the Hypex takes its signal, so that relieves the need for giant output transformers. Check the tube amplifiers frequency response spec; it should go down to 20Hz or so within a dB or so.

 

[Zek]

Am I making sense?

Yes, if tube amp works as preamp for Hypex.
We don't know how the crossover in the speakers is designed and how it works.

 

[Jungstar]

Did you ever find an AMP? and finish the TG TL III?