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

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.

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

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.

If your pre-disposed towards tubes, by all means get a tube power amplifier. But they are not "high current" devices by nature. A 60W power amp of any design, will not produce the transients and dynamics of a much higher power amp at higher sound pressure levels. And this is compounded by low impedance, low efficiency speakers. So it does get back to what types of music you listen to and the SPLs.

For an inexpensive solid state alternative with good high current output characterisitics I would consider the older Parasound amps. Not the Halo series (although they are not bad) but the earlier out of production models. Most were designed by John Curl, who also designed their much more expensive JC1 monoblock power amps.

One of the best, IMHO, is the HCA 2200ii, if you can find one. They run from about $500 to 850 used. Massive output current rating of 60 amps (90 amps surge) and this beast will drive 2 ohm loads no sweat. So the maggies are no issue. Very fast and open sounding amp.

They also made an HCA-3500 which has true dual mono power supplies and seperate amps (like two mono power amps in the same chassis), with a design similar to the 2200ii.
It has two power cords, one for each channel! 350 W/channel and a wopping 120 amps surge current capability. If you are lucky you may find this one used for under $1000.

Some believe that these earlier HCA versions rival the much more expensive JC1.

They also produced other versions of lower power ratings like the HCA-2205, HCA-1500, HCA-1000, which you can get a lot cheaper. But due to their lower power, the differences between these and a 60 W tube amp will be correspondingly less (from an output power perspective).

I had an HCA 1000A for years...bought it new actually. Great sounding amp with tons of power...input level controls, built like a tank. Sort of all the amp one needs really.

I don't think tube amps are for everyone...fiddly things really, and they're actually dying before your eyes even when working properly...but if you're into the "amp participation" thing of swapping out tubes and looking at the electron transfer glow they can be fun and sound sweet.

Thanks to all for the detailed advice. I have much to mull over.

Having heard many an amp on Maggies, I would look to a decent 60-80W/ch or better tube amp for best sound with Magnepan. I have heard the Rogue Cronus Magnum integrated for example sound very good, especially with a nicely integrated Rel sub in the mix.

Maggies like power but are not necessarily current hungry. They can go loud but their biggest strengths relative to others are at lower to moderate listening volumes IMO.

Similar power tube amps in this range sound different from SS equivalents at higher volumes largely due to the soft clipping characteristics of most tube amps as volume goes up.