Tube Friendly Speakers

[sorenj07]

Hey Soren -

By the way - when I play the kind of music you like on the Cerwin-Vegas with the Velleman cranked up (95 watts per channel) I have broken glasses in the kitchen, two rooms away ... scary !

... tom

yeah I just got the D7's, almost gave my young frame a herniated disc taking them up to my room but they sound pretty amazing. my crap little Sony receiver is driving them right now but I'll have all the parts (except for chassis) for my monoblocks today, if all goes well, so I'll start a new thread about that. All film caps in the psu :)

[TomMcNally]

I went the no electrolytics in the power supply route with my 300B ... it should have been monoblocks - it weighs about 60 pounds ...

[Hi-Fi Low-Life]

Can someone post a synopsis of why non-electrolytics are desirable in the power supply? Thanks!

[mesherm]

The overall performance of non-electrolytics like film and film/paper in oil is better in power supply duties. First off, unlike electrolytics, they have no polarity. Also their ESR (effective series resistance) is way lower although the new switching electrolytic caps are pretty good.
Motor run caps especially are specifically designed to use at 60hz, are self healing and very low in the loss dept.
The downside (and isn't there always a downside?) is that films and oil filled caps take up a lot of room.
The higher power your amp has the more filtering your going to need.
You can see how much space is taken up in Tom's amp and its only putting out less than 10 watts. Imagine how many motor run caps you would need for a ST70 or a MkIII?
Many people will however use a Solen Fast Cap or a motor run cap as the first cap after the rectifier tube on higher powered amps since that is the best place for them if your going to use them. Otherwise unless your building a SE amp you will probably end up using good quality electrolytics.

[Blooze]

I've got a pair of Pi Two Towers that I run my little 0.9W 12B4 amp into. At 96dB efficiency they put out plenty of sound in my 15x15 bedroom.

It sounds pretty good on my old Polk 5B's as well, even though they aren't as efficient as the Pi's. The Polks I bought new in the early 80's and still think they are some of the best bookshelf speakers I've heard.

Also picked up some Klipsch Heresy's this summer at a yard sale for $100 in great shape, but haven't tried them with anything but my SS rig.

Have some ART array's to build this summer. They say these should be good with low power SET amps. FredT used his BH gear with them to great success.

Tom -- that amp's a beast!!

[sorenj07]

I'm strongly considering dabbling in a smallish triode amp. I love headroom but 98dB efficient speakers leaves a few options. My bedroom is 16x12x12 (lwh) so really not much power would be needed. I'm considering picking up some plinker 6EM7/6EA7's and running them SET or maybe PP into the cheap Edcors, to see what happens...

http://tdsl.duncanamps.com/show.php?des=6EM7

10W plate dissipation, built-in preamp triode. plate resistance of the little guy a little high at 40K but not impossible to deal with. might make a decent LTP, precluding the need for any other tubes :D

[wiredbecker]

The 101db Pioneer CS-77s can be had for a song

[EWBrown]

Some of those 70s vintage Japanese made speakers were very efficient and the woodworking, and the fancy wooden grilles were quite beautiful.
I remember finding these at the PX over in Long Binh in Sunny Southeast Asia, for ridiculously low prices. Along with the newly emerging (and not so nice-sounding) SS receivers and amps.

At that time I wasn't overly impressed with this kind of speaker, basically because they were usually connected to an early 70s vintage SS amp or receiver, which was usually a not-so-hot performer, and these speakers brought out and accentuated that "badness" to the last decibel... But, hook 'em up to a decent tube amp, and the sound is almost magical...

I see these at local flea markets and yard sales from time to time, I'll have to snag a pair next time I run across some.

/ed B in NH

[wiredbecker]

They're really common nowadays. At least around Northern California. Last weekend I found two sets of Pioneers and some Marantz alnico drivers all for under $50. Didn't buy 'em. Acoustic Research are really common too. Well AR4s anyway.. I haven't found the AR3s yet. BUT I WILL!!!

One thing to watch out for with these old Pioneers are the decaying tweeter surrounds. The woofers usually are solid.. it's the tweeters that go. The grills are held on by four philips screws, one discreetly hidden in each corner near the frame.

[EWBrown]

A lot of the 60s and 70s vintage speakers will have rotted out surrounds, especially those with foam surounds. IF the speakers are cheap anough, the cabs are a bargain by themselves, and can be fully re-populated with new drivers and crossovers (Parts Express, etc). WIth most commercially made speakers, the cost of the cabinet is at least 80% to 90% of the total cost... And a lot of the speaker manufacturers really cheaped out on the crossovers.

Speaking of old speakers, on the TV progtram "That 70s Show" the speakers down in the cellar rec-room have the grilles off, and the (white cone) woofer end is up, the tweeter end down. Strange...

/ed B in NH

[EWBrown]

Madisound now has the BK-20 cab kits (sold as "flats" ) that fit the FE206Es and other similar Fostex 8 inch FR speakers.


Price is $210 each, and they are definitely larger and heavier than the BK-16s (which are $98 each).

They're a bit hard to find on the website, so I saved y'all the detective work...

http://www.madisound.com/catalog/produc ... ts_id=8282

/ed B in NH

[Shannon Parks]

Nice find, Ed! I was hoping that they would make a kit for the 8" speakers. You have a pair of those Fostex ready, don't you? Hopefully it will only be another month until I can move into my new listening room and I can break my pipes in.

[EWBrown]

I do have the FE206Es, but they are residing down in my NC place (just like I truly wish I was there right now, instead of enduring theis nasty evil NH winter storm).

I was gonna build up something down there last summer but the nice sunny weather lured me outdoors most of the time.

I'll probably get a pair of the BK-20 kits and leave them "flat" (as in unassembled) until I get them down there next summer, then I'll have something for the lower powered SET amps. The vintage Bozaks are great, but not high efficiency. Even the little booklet that came with them never mentions SPL or efficiency.

I had stumbled across the BK-20s last week, and had a devil of a time finding them on the madisound website, they are more securely hidden than the UFO secrets in Area 51 Yellow_Light_Colorz_PDT_04 Yellow_Light_Colorz_PDT_02 Yellow_Light_Colorz_PDT_01 Yellow_Light_Colorz_PDT_09

SInce I already have the T90As for the BK-16s, I'm sure that they will perform well with the BK-20s. Don't forget the "terminal cups" too, they have the right size for the ready-drilled opening and they are relatively inexpensive.

/ed B in NH

[Slartibartfast]

I do have the FE206Es, but they are residing down in my NC place (just like I truly wish I was there right now, instead of enduring theis nasty evil NH winter storm).

Damn it man! Get in your car and drive down. Give me directions and I will meet you there. Yellow_Light_Colorz_PDT_16 I am always looking for an excuse to go to the mountains.

[wiredbecker]

DYNACO SPEAKERS A25 - $40 (san leandro)

http://sfbay.craigslist.org/eby/ele/509600184.html



Obviously they have replacement grills and one has a damaged woofer. The price is right and worth picking up if you have a spare woofer to plunk in.