Solid State Pre-Amp: OK to Use With Tube Amp?

As a general rule of thumb, I think for Magneplaners under $1000 that you'd be better off with a strong solid state amp. I feel that you would have to spend more for a tube amp powerful enough to drive the Magnepans.

Michael

SS pre is very ok to use. The most important place to have tubes is at the amp anyway. I'd try to get tubes in there with the amp. Just my thoughts.

My NAD amp delivers supposedly 55 watts per channel. This Jolida 502a delivers 60 watts.
http://boston.craigslist.org/gbs/ele/2952542156.html
It's available to me locally. What do you think of it? There are several of the newer model 502's for sale here at 'gon.

Franz456,

Sufentail's guidance was close, but IME not quite on. Your speakers do require a certain number of watts to produce a given SPL in a given room, but that's all power (watts) will buy you. How many watts do you need? It depends on your room and your preferred listening volumes. Nobody knows that but you, but if the NAD plays loud enough without sounding horrible (clipping) then the Jolida will too. The diffference between 60 watts and 55 is barely significant, and would only be audible if you drove the amp to full output power, which is unlikely.

Much more important than a 5 watt power differential (or even a 200 watt differential) is the ability of an amp to deliver current (amps), instantaneously on demand. Your speakers are somewhat current-hungry and an amp whose power supplies aren't up to snuff will sound compressed, muffled, muddy and dynamically compressed compared to an amp having better power supplies.

Now the bad news: good power supplies are expensive. The power supplies in my amp cost more than your NAD and that Jolida put together. Not boasting, just pointing out that this is the area that separates the men from the boys in amplifiers. My amp produces just 57wpc but I guarantee it would blow (has blown) the socks off any 200watt SS amp costing less than $10K, even driving somewhat difficult speakers like yours. It's not about power, it's about clean, unmodulated and instantaneous current delivery.

Great power supplies cost money, which means that amps in your price range are necessarily compromised. :( That said, I'm confident the Jolida's power supplies are significantly more robust than the NAD's. If it's in good operating condition I'd expect a sonic improvement.

Keep in mind this distinction between power and current. They are not the same and power is rarely the more important consideration. Manufacturers of amps built to a price point emphasize power (watts) because it's easy and cheap to increase power, especially in a SS design. The same manufacturers never talk about current delivery. That's because they can't do it well at their price points.

Hope this helps,
Doug

As an aside: I have a 60 watt Jolida (new) and it is interesting to hear how the thing sounds at that wattage, relative to SS amps I've owned (with high current power supplies). I really don't buy the "tube amp wattage sounds like a multiple of SS" line...watts are watts and clearly power supply reserve is what matters there...but the SOUND of a tube amp when played loudly (relatively) is so completely different from SS I can see why the power claims are made. SS odd vs. tube even harmonic distortion is often used as the explanation, but an analogy I can make is with guitar amps...I've tried plenty of modern low powered well designed SS guitar amps (so called "practice amps") at 10 to 20 watts and they're OK. But just OK. My current primary guitar amp is a 15 watt (!) all tube little monster that I use on its "5 watt" setting most of the time...even in small clubs, and it is SO much better than any low wattage modern SS amp I've tried that any comparison is laughable. The thing just "feels" heartier somehow, and the low wattage allows exploitation of the output tubes more than just overdriving the preamp, and that's magic.