Monitor 5 and amp matching

[shaneybob]

I have a pair of Monitor 5's that I purchased back in 1984-5?. I have ran them with a Carver receiver and right now with a 55W vintage Kenwood 6100 which both work well. I have a new SE tube amp (10W/channel) that only has 8 ohm taps on the way that will be used with speakers of 96dB sensitivity. Will the Monitor 5's cause any problems if I use this amp with them? I never listen past about 10-11 o clock on the Kenwood and they are plenty loud enough to run my wife and kids off. I realize the amp will be working a little harder, but at moderate volumes should be OK I think?

[hoosier21]

no problem, hook them up and enjoy

[ND13]

Yeah, and tell us what you think, how does it sound???

[shaneybob]

I'll do that for sure when I get the amp in. I'll run it on the Polks, then on the Two Pi Towers and compare. I've heard it on the Pi's and it sounded wonderful. The Polks sound really good on the Kenwood though. Lots of punch and good staging. The Kenwood has watt meters that I've never had above 1.5 watts. It's so lound at that point I fear for the speakers. These probably aren't accurate, but I'll bet they're close. It's amazing how many people don't realize that a little power goes a lot farther than they think. Course, having 50-100W headroom is very nice, too.

[mhardy6647]

The Monitor 5's are a tad inefficient for a low-power SE amp. If you've really got 10 wpc, though, you should get pleasant sound from a pair of 5's. As a reference point, my Monitor 7A's are not efficient enough for practical listening with Bottlehead Paramour 2A3 SE monoblocks (3.5 watts per).

I take it that your 10 wpc tube amp is a single-ended pentode amp, or an SET with paralleled outputs... or do you have a high-voltage, transmitter tube SE amp? I'm curious as to what you have.

BTW, assuming your new SE amp is running in Class A all the time... Class A amps work hard all the time (i.e., the outputs are full "on" at all times), so it really won't matter how efficient the speakers are in this regard. You can rig up a frying pan over the outputs and fix omlettes while you listen :-)

[shaneybob]

The amp is a Nelson Audio SE8. Put's out 10 wpc driving through EL34's. Don't know if it's Class A or not, but my guess would be yes.

Had a problem with UPS destroying the first one. Don't ask me how as the thing was packaged to the extreme. So I'm waiting on the claim service so I can replace it. Never actually used it at home yet. Hopefully in the next couple of weeks I can get the replacement in.

[mhardy6647]

ahh, I see...
http://www.mrtwochannel.com/SE8i.html

[shaneybob]

ahh, I see...
http://www.mrtwochannel.com/SE8i.html

Yep, that's the one. I listened to a Zen, a Stoetkit, a couple of SS's, and the Nelson . It came down to the Stoet and the Nelson and I don't feel comfortable enough yet to build the Stoet so the Nelson it was. It's all point-to-point wiring also, just has the "fancy--(read inexpensive)" tube cages so it looks somewhat nicer. Even though it comes from China it had all decent parts in it, no no-name brands. Dales, Solens, Electro-H tubes as Nelson imports parts instead of using the cheap chinese stuff. I really just like the way it sounded and that's what mattered. It could of looked like a shoe-box and I wouldn't have cared. I really want to learn how to make and troubleshoot tube stuff though, would be fun I think.

[mhardy6647]

The Zen is really low powered. I have an SE-84B and it wasn't up to driving my Klipsch Cornwalls, which are (depending on whom you believe) 98 to 100 dB/W/m efficient! It is a nice sounding and refreshingly simple little amp, though. The Zen prefers a lower impedance load, since the OPT secondaries are 6-ohm.

I don't know of the Stoet, but I will say it's fun to build one's own, and a good kit makes that much easier than from scratch. The Bottlehead products are quite nice in that regard.

The Nelson sounds like a pretty good deal based on your comments, and there is nothing at all wrong with using EL34's as SE outputs, even though they don't have the cachet of the usual SE amp output DHT darlings.

See if you can find a pair of original series (or at least early series) DCM timewindows cheap. These are TL-loaded and remarkably efficient IME... my Bottlehead Paramours drive them OK, and they're really spiffy with an EICO HF-81 (ca. 12wpc EL84pp).

[shaneybob]

I've thought of making some TL's using Fostex drivers just for fun. I've heard a few single driver speakers and they sounded pretty good in a smaller room.

My next project is an entry level turntable and line stage. I've been looking at the Bottlehead Seduction after hearing so many good things about them. That would give me some kit experience, also.

I've looked at some of the darling designs. I'd like to hear some of them.
I've got a revised Millet-hybrid headphone amp I'm in the process of building that uses the old 12FK6 tubes at about 24-28V. I feel a whole lot safer messing with this to start with.

[mhardy6647]

I built the original version of Pete's headphone amp and have used it as a preamp, too. Actually, that SS buffer will drive high-efficiency loudspeakers remarkably well, too! I know what you mean... PCB really makes construction easy, and no pesky HV to kill you if you get careless :-)

I actually didn't mean the literal "Darlings" (though they are fine amps)... I was trying to refer to the tubes that are figurative "Darlings" of the DHT/SET crowd: 2A3, 300B, 45, etc. :-)

Fostex drivers are mighty fine FR's, especially for the $. The shielded FE207E's produce nice sounds in a simple, ported ft^3 box. The 206's are probably even better, but Qts is so low that you have to go to more esoteric enclosures or add a subwoofer.