[fiveoclockfriday]

Hi guys, fairly new to pre/power amps here, I've had integrateds for years. I'm getting a bit caught up on voltages, impedance, etc.

I recently picked up a pair of Inline Maraschinos. Our family is in the process of moving so I'm just in a temporary setup right now. I'm using a DAC w/volume control straight into the amps. It outputs 2v max. It sounds very, very good.

But, I know the Maraschino specs list "2.4v for 230w into 4ohm". The actual max output is 250w into 4ohm, so I'm guessing they actually prefer closer to 3v?

So, I'm obviously not getting everything I could with a higher voltage source and possibly preamp. Is this going to be a large difference? Is it likely affecting sound quality or just power? Thanks in advance.

- Eric

[konut]

What is the output impedance of your source? What is the input impedance of the Maraschinos? What is the nominal impedance and sensitivity of your speakers? Without that information, especially the speakers, the question is unanswerable.

[fiveoclockfriday]

Konut,
Thanks for your help.
 
Maraschino input impedance 20k true balanced.

Speakers are KEF ls50 - 85db, rated 8ohms, but dips to 3.2 - considering them a 4ohm load is what I've seen other people do.

Dac output impedance I'm having trouble finding. It's IQAudio Pi-Dac+ i2s dac. I'll try to contact someone to find out.

[konut]

Okay! As long as the IQ has a reasonably low output impedance, as most solid state devices do, you should be okay on that front. The questions now are, how loud do you listen, and how far up the volume scale do you have to turn up the IQ to achieve that level? If you're only turning up the IQ in the middle of it's range to get acceptable volumes, then you're good. If you have to turn it up all the way, then you might consider a source with a higher output.

[mojave]

But, I know the Maraschino specs list "2.4v for 230w into 4ohm". The actual max output is 250w into 4ohm, so I'm guessing they actually prefer closer to 3v?

The Maraschino is rated for maximum output at 3.1v. However, input sensitivity ratings are done use 1 kHz sine waves. It takes a lot more output capability from a DAC to drive an amp to full power when using music or movie content.

You don't need to know the impedance of anything to figure out how much more maximum output you will get with a higher powered DAC. 2v is +8.2 dBu. You can use this calculator. Most balanced DAC's will output between +18 dBu to +24 dBu. I use +20 dBu with my Maraschinos. This is 11.8 dB more than you are able to output.

To figure out what you get with a different output you do the following:
1.  Convert maximum output voltage of DAC to dBu.
2.  Subtract the 8.2 dBu (your current DAC) from the dBu output of the higher voltage comparison DAC
3.  The number you get is the actual decibel level increase you get with higher voltage

Meyers Sound is the only company I have seen that provides the proper specs. Here is an example of what they say on their amps:

Nominal Input Sensitivity  +10 dBV (3.2 V rms, 4.5 V peak) continuous is typically the onset of limiting for noise and music
Input Level  Audio source must be capable of producing +20 dBV (10 V rms, 14 V peak) . . . to produce the maximum peak SPL

Their input sensitivity is similar to the Maraschino, but you can see that a much higher input level is actually required to reach peak output.

[fiveoclockfriday]

Thank you Mojave, fantastic information. It seems I'm definitely missing out on much of what the Maraschinos are capable of.

Once we get settled, I will look into either a higher voltage DAC or a preamp setup.

[konut]

I use +20 dBu with my Maraschinos. 

What source is that?

[mojave]

What source is that?

MOTU 1248 - I used it with 5 Maraschino's at Rocky Mountain Audio Fest last year.

I previously used a Lynx Aurora 16 Thunderbolt with the Maraschino's. The Aurora also has +20 dBu on the outputs.