Amplifier - Speaker matching

Hey guys, and PS Audio. I am a new comer in pursuit to find a solution. I have no experience in Hi-Fi. The task is simple to find a good pair of speakers for Sprout 100. In my region we do not have a wide range of choice KEFs, DALI, Aurum Cantus and some others. Do not like KEF, too sensitive and flat sounding to me.
Sprout 100 is 50W@8Ohms, 100W@4Ohms, the best pricing match we have is DALI Oberon 3 bookshelf 88.5 dB sensitivity, 6Ohm impedance, 25-100 Ohm recommended power. No data about peak or any specific optimal power rating.
I supose that @6Ohm Sprout will deliver about 70-75W RMS, which is 25W less than speaker maximum recommendation. Internet tells that it is optimal when an amp is more powerfull than a speaker. Sprout100 to DALI Oberon 3 is not the case. Actually you won’t find a modern speaker to be lower than 100W, or 50W for 8 Ohms.
Does it mean that Sprout won’t be good amp for the mentioned DALI, how to find a pair for such low Wattage amp? Most speakers are:
20(50) - 150(200) W@ 8Ohm
25 - 150W @ 6Ohm
30 - 200W @ 4Ohm
Almost all speakers are higher than 100 Ohm Sprout, help me to understand this issue. I see no modern speaker to be 10-40W @ 8Ohm, or 25-70W @ 4Ohm, which will be ideal for the Sprout.

Welcome Alexander.
The answer will depend somewhat on the size of your space and how loud you want to play at your listening position. Other than playing very loud and having enough power to prevent clipping at speaker low impedance frequencies I cannot explain the internet recommendations. Hopefully someone else will provide a better explanation.
I have a Sprout paired with 8 ohm nominal (7 ohm min), 88db, 100-20k +/-3 db, Rogers Sound Lab CG4 speakers in a 3.5m x 3.5m space. They play plenty lounge enough for my preferences.
The Dali’s frequency range begins about 50hz, and maybe dips to 5 ohms, so I suppose will place more demand on the Sprout.
PS Audio pairs the Sprout and Elac B6.2 which has similar specs and impedance characteristics. Good enough for PS Audio is probably good enough to provide some confidence?
Are you able to audition the Dali’s and return if not satisfied?

1 Like

Welcome!

Hello allan, thanks for sharing your experience. Looking at Elac and Rogers Sound, I’ve got an idea that it is not mandatory to have an amp more powerfull than the speakers. The amp maximum according to your reply should be, at least, 50% of speaker’s max RMS to pair safely with acoustics and to provide an appropriate sound experience.
The second thought is not optimistic, it is almost impossible to find a speaker for Sprout category amp whose specs will be covered by the amp. And user should choose between a modest few hundred $ speakers and a couple thousand amp, strong enough to get everyting from them, which is not equal marriage to me. Or, both expensive units within a 5-6K USD budget in total.

Hello, the load capacity of the speakers says less about the compatibility with the amplifier and is not important. The maximum load on the speakers only shows when the membranes fly towards you and overload the voice coils. A small amplifier that starts to distort and vibrate on high volume can also damage a speaker. That first.
Which speakers fit your amplifier depends on how loud you want to hear? The minimum impedance of the speakers should not be too low. With an 8 ohm speaker it is usually less critical than with a 4 ohm speaker. The amplifier has an easier time controlling the speakers. Now to your choice of speakers. If you want to be louder with little amplifier power, a speaker with high efficiency is the better choice for you. Floorstanding speakers or bookshelf speakers? The best speaker is 8 ohms that have no impedance below 4 ohms, so you are on the safe side. The higher the efficiency of the speakers, the easier it is for your small amplifier. Should it be ready-made or is self-construction also an option? New or used? For example, a horn loudspeaker (broadband) has a very high level of efficiency.
But it should work with the favorite Dali speakers.

Greetings Andreas

2 Likes

OK, thank you for the very comprehensive reply. Where is the boundary for the limiting sensitive speaker from not sensitive one? 87dB is it sensitive enough or we should name a speaker sensitive if it is 92db and more?

Welcome to the forum!

I dont think there is a particular number that defines high or low sensitivity. It is a measurement of loudness in decibels at 1 meter from the speaker cone using 1 watt of power. I would say anything over 100 would be considered high and anything below 85 would be considered low. Also as mentioned the lowest resistance in the speaker impedance is also a consideration.

The low watt tube amps (<5 watts) will need high sensitivity speakers in order to play very loud. Speakers in the mid 80’s require more power but the Sprout should be fine unless you have a very large space and sit a long way from the speakers.

We have a Sprout with the Elac speaker package and they are in the high 80 range if I remember correctly and they play plenty loud.

1 Like

The DALI Oberon 3 will work wonderfully with the Sprout.

Do you already own the Sprout and able to bring it to a dealer to try out speakers with it?

Yes I do own it, but going to a dealer is quite complicated, that is why I started this conversation. I will do the test for sure

1 Like