yaffstone

I've been reading some and find that there are numerous upgrades available for an ST-70. The power supply quad cap replacement seems like a great idea. Has anyone done the triode input stage conversion? Wonder if this one is worth it. BTW, I have quite a few soldering irons, DVM's an o-scope, and some experience with solid state design and trouble shooting. Never worked on or listened to tubes, but then I guess it's never too late to start. Thanks for the advice, David

I've just done a BIN for a Dynaco St-70. Pretty pristine original shape. Any pointers would be appreicated. Should this be left turned on so the bias voltage doesn't drift? Should I leave it alone, or apply upgrades like modern capacitors etc? Thanks for any advice. BTW, this amp will be driving a set of k-horns. Cheers, David

I agree with the general opinion: MP3 is not suitable for home use, but it is just fine in the average car or truck. I've been on the road for 3 weeks now with an MP3 juke box. It's far better than 6 boxes of CDs floating around the cab and there's no way to hear the difference over the road noise and diesel engine. Everything has its place :>

I used a cabinet scraper with good results on my LaScalas. I was only interested in refinishing the outter portions, not the inside corners in the bass bins. It only took about 30 minutes per speaker to scrape all the old finish off. Light sand afterwards and then on to re-finish.

Building a wall to put your system in is a big idea. Think big. Think Cornwall. Ported to the front and nice big bass. Easier to find than chours.

Forte are great speakers. They'll blow away the KG-4. It's a slipery slope though. You might want to skip all the stuff in between and just get a pair of k-horns.

I've got a pair in teak. Dilynl did the vaneer work and posted pics some time ago.

D-man is right, so set the multimeter to V AC and see what you get. Also check what is going into the amp before blaming the amplifier.

You can get a 12.5 uF caps, polypropylene film in oil from alliedelec.com I've used them and like them. The Allied Stk# is 225-2208. ASC part number is X387S-12.5-10-330. These are rated at 12.5 uF but I measured 12.7 uF. That's within 2.3% of the desired value. Price $6.74 each. http://www.alliedelec.com/cart/ProductDetail.asp?SKU=225-2208&SEARCH=ASC&ID=&DESC=X387S%2D12%2E5%2D10%2D330 Hope this helps.

IMHO the Fortes would do just fine as rear surrounds. You'll get the same general timbre as the Heresy but more bass response.

We always left a shorting wire accross caps in the lab because they can charge back up left on the bench. Once shorted, they're safe. One way to do this is to make a wire with an alagator clip on one end and attach that to ground. Then hold the insulated part of the wire and touch the metal to the cap lead on the high voltage side.

You could get more Fortes to match the Fortes! A Belle or LaScala would do well for center. I would seriously look for more Forte for your rear surrounds.

Dark Star by the Grateful Dead. If they stay and listen, they're harmless, you and your girl can do what you please. If they are generally anoying, they will be annoyed and run away!

Get a Belle. It's not as deep as the khorn or scala and will look good under the tube.

The beauty of it is that Pi is simpler and more accurate at once.

Ditto.

I don't know about the reference series but Outlaw Audio sounds great with the heritige line.

I think there is some space in the upper cabinet to rotate the horn a few degrees. Since this would require re-mounting, one could design a wedge, remount the edge of the horn which will be close to the front more towards the center of the cabinet, and rotate the driver. This would turn the horn without modifying the looks. This is speculation however. I haven't made drawings or even measured.

The bass on Belle and LS is already forward facing so there's no need for a reflector like with the k-horn where the last fold is the wall. There is a thread on adding a port to the LS though. Increased performance has been noted with the addition of the port.

I had both belles and cornwalls. I sold the cornwalls even though they had more in-your face bass. I like the high and mid-range of the belles better. Replace the original caps in the x-overs for great sound. Even better, look into one of the newer x-over designs. I'm sure you'll be happy either way though. They're both great speakers! This choice should be the worst problem any of us ever has.

PIO = paper in oil (old design, most upgrades use metalized polypropylene) Hovland Musiccpas = expensive audiophile caps voltage conditioned = broken in by powersupply instead of 50 hours of listening Crossover capacitors are replaced with higher quality ones becasue the speakes will 99.999% of the time sound amazingly better. Cost varies but can go from $30.00 for a pair of speakers to $30.00 per capacitor, upwards of a few hundred dollars depending on crossover design, capacitor values, etc.

It sounds different partly because even though you can't hear above 20khz or so the second, third, and higher harmonics are lost due to the limited sampling rate. They still exist in analog. In audiophile terms, you may perceive a lack of depth in the digital representation. The newer digital techniques are clearly better than back in the 80's but there is an intrinsic limit by the act of digitizing. BTW, I'm not an analog snob, I listen to both records and CDs.

That's like saying that digital pictures have the same resolution as film. It just isn't so. You can't have more information than the sampeling rate allows. Analog is continuous, digital is discrete.

Are these surround sound receivers? If so you have to program them to set up gain on each channel. If the baseline gain is set high you will need less on the volume knob to produce the same actual sound level. None of this has anything to do with digital sound containing more data. In fact, all digital sound sources contain less data than analog since it is digitized (where's the info from the space between discrete time points?, It's' lost!) There can be different output levels from different D to A converters so that could be a factor also. Don't go to the issue of 5 or 7 channels versus 2 for analog, this is a processor speed issue and has nothing to do with line out signal levels.

Great score! Congradulations. You're gonna love that setup.