The 'NEW' YAQIN MS-20L Integrated Vacuum Tube Amp Thread - Page 26

Ha, shows how well I read!

Since we moved to another page... I still need to know what products, from this company, I should be considering.

Although I listen loud at times, I would like to at least consider a tube setup.
I need an amp and a phono sound stage.

• speakers: 84db sensitivity B&K 686 bookshelf size speakers (thirsty)
• room: 14x12 room
• music: indie rock and jazz
• sources (2) vpi traveler, w/2m blue cart & also an iPod (at times)

Thx again

I was running Magnapan MMGW that had a sensitivity 88 at 5 ohms. So they were difficult to drive. I really liked them and they played loud with the ML-20. I did end up repacing them with Energy Veritas 2.4's. It was not because of how loud they could go, they went plenty loud, it was due to the fact the MMGW could only go down to 100 hertz and I was having a challenge getting subs to match with my tube system and these speakers. I ended up getting the Energy's at such a great price too, I couldn't resist. The only way you are going to really know how they sound with the ML-20 is to give it a try. I really like the amp and I am so glad that I took the plunge. In fact, I am listing to some vinyl right now, and how sweet it sounds. I have the Yaqin MS-22B between the amp and my Music Hall MMF2.2 record player.

Best of luck,

Jeff

I am using modded Klipsch Heresy II (sensitivity 99) and two Martin Logan Dynamo 300 subs. I am getting all the volume I can stand.

Personally I wouldn't run speakers that are less than 90db with an MS20L.

Jeff,
Is your MS22b modded? How do you like it?

I had run Magnepan MG1.5Qrs on the the MC100, sounded fantastic at low to moderate volume, but broke up at the level I liked to play at. The bottom end of the bigger maggies is a bit lower, and combined with KT88's felt solid and well-rounded.

You can still use tubes, hell, the 20L may be just fine for you. But if it's loud you're after on occasion, a little more available power will be useful. You can still go with tubes and get 100watt/channel, just going to cost alot! You can use a tube pre and solid state amp, or you can just go with a proven 2-channel receiver, like the HK everyone is using and a sub to fill out the bottom. Options are near limitless and a hell of a lot of them are going to be good.

It's not true at all that you can't get loud beautiful sound with tubes. You definitely can. I have never turned passed the 50% mark on my Yaqin amp, it's pretty damm loud. You're honestly good with any speakers 90db sensitivity and above. I have a couple of Tannoys right now at only 89db sensitivity and it is driving them fine. There are plenty of efficient speakers, like the Klipsch reference line for example, you're getting 96 or 97 db sensitivity. Oh it's going to be plenty LOUD.

We are not talking about 90db and up speakers now. We are talking about the 84db B&W's that he has aready bought.

This!

That?

The difference between a 50w amp and a 100w amp is only 3dB. Even your 84dB/w/m speakers should get up to around 100 dB with the 50L. Plenty loud for me.

100 db at 1m......changes an awful lot in an actual space and listening position at a distance of quite a few meters. And the Yaqin amps, by looking at design, even with basic engineering and physics understanding, definitely do not put out anywhere near what they a rated at by manufacturer (noone has done proper bench testing of them yet to get real numbers)

My 22b is not modded. It works great but I do not have anything to compare it too.

Jeff

I use 87db Dynaudio Audience 82's with my 20L, it goes plenty loud!
Given that I recently had a 22w Line Magnetic 845 SET driving them and
even that had enough grunt I would have thought that 84dB speakers with the 20L
in UL mode should be ok in an office.

I have heard less powerful Shindo amps running 85dB Harbeth's with no problems.

Ofcourse, my interpritation of 'Loud' may differ from yours

I find that statement curious...please elaborate.

Getting those speakers to 100dB would require 32w btw. Well within the capabilities of an EL34 push-pull amp.

to the first question, in simplest terms: Plate voltage is too low to get that much power from EL34.

As to your statement... I will say again what I said a couple of posts back.....that 100db output that you are speaking of is at 1m, not at listening position. Basic math on it is -6db for every doubling of distance. So, I will do it for you....2m away from your 100db output is 94db, 4m away is 88db. So, in an smaller room like Ryan is using, lets say he sits 2m from the speaker, to get back up to that 100db level, with no increase in distortion across the frequency range of the speaker, would require 128watts. Now you begin to see why so much power is required to get a reference level from a low-efficiency speaker.

My Yaqin MS-534 blew up! I turned it on and the thing surged with a small flash on the top plate and died. And it's connected to a great surge protector, so it was just poor construction, I guess. I have no suitable replacement and don't know where to repair it. Is such a surge repairable?

Sounds like exactly what happens when an output tube goes. Did it just blow the fuse?

If so, just time for a new set of tubes.

that's two people that have stated the yaqin puts out nowhere near its' rated power. if this is true how has yaqin got away with this lie and get all this good press on forums? grant fidelity use to carry yaqin, were they in on it? there's a guy in the us that sells them, is he in on it? if yaqin wanted to lie why stop at 50 watts? why not claim 100 watts since they are so good at getting away with it.

IIRC, the maximum plate dissipation of an EL34 is 25 watts. They're using two tubes per channel, so they're taking that number and doubling it to get 50 watts. It's a bad calculation, though, because they're probably not running the tube at the voltages necessary to get that dissipation. And even if they were, that's 50 watts of heat being dissipated from the plates... not 50 watts at the outputs. They're either not aware of how things work, or (more likely) are deliberately using believable-sounding (albeit incorrect) "funny math" to get a bigger number for marketing purposes. The dealers are simply repeating the manufacturer's numbers, same as most dealers do in any industry.

I figured the "real" wattage is about 35 per channel in ultra linear mode. The number doesn't really matter that much though, what matters is matching the amp with the right speakers.

take a look at this, vtl is getting 60 watts out of 4 el34. why can't yaqin get 50 watts? is vtl fudging the numbers too?
http://www.vtl.com/pages/st85specifications.html

jolida also gets 50 watts out of 4 el34 tubes. are we picking on yaqin?

It all comes to transformer quality and plate voltage for tubes. Yaqin is not the best in both. I did measure MC-100B myself. 35W was a clipping point. If you read tube amplifiers reviews in Stereophile (they do measurements of reviewed samples), they rarely were able to confirm power specification.

Mboldda1, no picking on anyone. Very few manufacturers have actual output rated, most are come to by flimsy math, I think numbers are come to by PR, not by electrical engineers or by bench-testing.

I own a Yaqin amp, I like it, I am not under the false assumption that my MC100 is putting out 65watts per channel, though, and I paired it with appropriate sensitivity speakers.

Instead of becoming defensive and looking like an *******, learn about the parts and physics of how valve amps work. Even without the equipment to do proper measurements, you can see by mathematics that something is not true

The manual for my yaqin ms-20l only states 40 watts output, not 50w as advertised on flea-bay.
It also states 180w power consumption, I have never seen it pull more than 138w.
I have 87dB speakers and it goes plenty loud, does it really matter?

Seriously who buys tube gear to wank on about watts????? That's for solid state boys!

Seriously? Dude...
415v on the plates of an el34 amp with fixed bias is quite capable of producing 50 watts of output.
http://en.wikipedia.org/wiki/EL34



Thanks for that.

Update on the Yaqin 6CA7T blue glass tubes.....not recommended.
They do sound very nice, but there are serious quality control issues methinks. I had to return 2 of the tubes to the seller, one red-plated (fortunately right in front of me so I could shut down the amp asap) and one introduced a nasty 120hz hum in its channel. To the sellers credit, he replaced them but 2/4 tubes being bad does not speak well for these tubes. There are better choices available.



I also picked up a companion for my Yaqin yesterday...bit of a contrast in philosophies, eh?

CIMG5439.JPG 3502k .JPG file

Nice Marantz!!

After much tube rolling I have decided to stick with the Russian 6P3S-E, they just sound better in my system. I have a matched quad of Electroharmonix 6CA7eh big bottles with 50 hours on them I am going to sell.

Thanks! Got it assuming it'd need to be recapped, but it's running to spec so i'm just gonna use as is for now. It's a friggin atom smasher...i'll use when i get the urge to annoy the neighbors.

Haven't tried the 6p3s-e's yet, but heard a lot of people really enjoy them!

I have an old Technics receiver I use in my garage that am in the middle of re capping.