Dave MacKay

Nope. Good amps and proper gain matching = low hiss, even with efficient speakers.

This is an interesting development. Lenbrook has a number of interesting firms under their umbrella and Cheskly has a great reputation. Thanks for bringing this to our attention.

Very interesting document. Thanks for posting it.

I agree with @jcn3. You will likely find the sound more pleasant if you toe the speakers in towards your listening position. However, you won’t need a lot of toe-in. I measured on-axis and off-axis performance of my La Scalas and found that they degrade significantly the further off-axis you go. Some people say to align the axes so that they meet in front of the listening position and others recommend a couple of feet behind. What works best for you will likely be determined by your room’s acoustics.

Thanks for your kind words. It was quite the learning experience. Before I built the THTLP subwoofers I went through two other subwoofers. One was a low-end Klipsch subwoofer that I got at Best Buy. It was not good. I bought an SVS SB1000 Pro subwoofer and really liked it (even though SVS recommended their larger 3000-series subwoofer as a better pair for La Scalas). I expect you'll be quite satisfied with an SVS subwoofer. Some folks on AudioKarma spoke very positively about the THTLP, so I decided that, rather than buy another SVS subwoofer, I'd try the THTLP. Building (but not veneering) a THTLP cost about the same as buying an SVS SB1000 Pro. With respect to the La Scala low-end running out at 50 Hz ... that's correct. Also, the La Scala bass bin stops acting as a horn for frequencies below about 104 Hz. However, you'll likely find that the acoustics of your listening room are dominant at those frequencies. You'll be able to experiment with a range of crossover frequencies on the subwoofer. The management of this forum frowns upon discussions of modifications to Klipsch products and of other vendors. To participate in a discussion about that, I'd encourage you to go to the "Klipsch Korner" on Audiokarma. Originally, I had wanted to keep my La Scalas looking as they were when I bought them: Birch, Raw. Heck, a neighbour even nicknamed them "the blondes" on account of their colour and the attention I was lavishing on them. I bought a sheet of birch veneer and tried a number of different finishes (with and without wood conditioner) but didn't find anything that I thought was attractive enough. That led me to consider both painting the speakers (which I rejected) and using other veneers (e.g., walnut, cherry, sapele, others). My speakers didn't have a grill to cover the squawker (mid-range) and tweeter. Because I was happy with the look of the exposed horns, I just sanded the horns and gave them a fresh coat of spray paint. If you have a tablesaw (or have a friend with one), you could easily mill suitable moulding for the frame. Or you cut make the grill frame out of fibreboard and cover the edges with the grill cloth. If you search this forum you'll find photos of a number of La Scalas, with and without grills. I expect you'll be able to find birch iron-on edge banding in widths >- 3/4". (I found some listed on Amazon and at Home Depot). However, if you can't, you could use maple instead. The difference between maple and birch would barely be noticeable. Good luck.

Thanks. At first, I wanted to keep my speakers light coloured. I even considered veneering them in birch to retain that look. After making a few tests using different veneers, I ended up going with Sapele. I veneered the speakers myself. I didn’t think I had the skill to veneer the bass bin (doghouse) so that painting them black was the best way forward that I could think of. I used Rubio Monocoat "Pure" to finish the speakers and subs. The “pure” (i.e., no pigments) finish might be worth considering for your speakers. I looked at Danish Oil, tung oil, wipe-on poly, etc. but — to my mind — they imparted a yellowish colour. To be frank, I was underwhelmed with how the La Scalas sounded stock. I ended up trying 5 networks (Klipsch AL, C***** AA, C***** A/4500, A** Universal A, and A** A/4500). Of those, the AA measured best but I preferred the sound of the Universal A. Even so, I still found the speaker wasn’t living up to my hopes. I ended up tri-amping the speakers using a MiniDSP Flex Eight DL instead of a passive network. That brought them to life! I documented that whole endeavour in a lengthy thread on Audiokarma’s “Klipsch Korner”. In my opinion, "going active" was transformative for the speakers such that -- again, in my opinion -- they sound far better than stock. The subwoofers made a big difference too. You’re right, the La Scala peters out of low end around 50 Hz. I added a subwoofer — then a second sub — because I wanted more low end than the La Scala could produce. I needed two subs in order to address some of the deficiencies of my listening room. The subs were a great addition. Highly recommended. I didn’t make any changes to how the squawker was mounted. It’s mounted to the back of the front baffle.

This thread presents what I did with mine.

I have similar vintage La Scalas. I built risers for my La Scalas to raise the tweeters to my ear level (at my main listening position). I haven’t been able to notice — or measure — any diminishment of the low end. A popular mod is a DJK port. In addition to raising the La Scalas, it improves the low end response.

From what you’ve described it sounds like the plate amp in the sub is defective. Can you take it back or have it repaired under warranty?

Are you able to test the sub using a different amp to provide the LFE signal. Would like to be able to isolate the issue to either the amp or the plate amp on the R-120SW. Also, how high is the gain setting on the subwoofer?

A fellow Canadian (from the GTA) chiming in … The price is excellent. Whoever buys them will be getting a fantastic deal. I bought a pair of beat up La Scalas a couple of years ago for $2800. I added SMAHLs for roughly $500. Repairing and veneering the cabinets cost in the neighbourhood of $1000 (no cost for labour since I did the work myself). La Scalas don’t come up for sale often in these parts. The ones you’re selling are excellent. It would cost more to build a pair from scratch or to try to bring a pair of beat up speakers to the calibre of the ones you’ve listed. Good luck with the sale.

I've been reading an old (1972) book (How To Build Speaker Enclosures by Badmaieff and Davis). A topic that I found to be of interest was how the area of the mouth of an exponential horn determines the lowest frequency that the horn can reproduce. I tried applying the logic to my vintage La Scalas, but the answers I get don't seem to be very satisfactory. I measured the area of the mouths of: a) the lens used with the K-77M tweeter (4" x 1.5") b) the K-400 horn used by the squawker (16.75" x 5.75") c) the La Scala bass bin (22.25" x 22") I then used those areas to figure out what the circumference of a circle with the same area would be (i.e., Radius=sqrt(Area/pi) and Circumference = 2pi*Radius). The thinking is that the lowest wavelength the horn can support should match the circumference, I divided the speed of sound (1125 ft/s) by the wavelength to get the frequency (in Hz). Here's what I came up with for the lowest frequencies supported by the different horns: a) lens used with the K-77 tweeter ---> 1555 Hz b) the K-400 horn used by the squawker ---> 388 Hz c) the La Scala bass bin ---> 172 Hz I thought the the K-400 got its name because it was intended for use down to 400 Hz, so the figure for it (i.e., 388 Hz) seems reasonable. However, from what I've read on this forum, I thought that the La Scala bass bin was supposed to be good to about 104 Hz, which is well below the 172 Hz that I calculated. I'd be grateful if anyone would care to help me understand this better.

And lightly sand or DeOxit all the connections and connectors get new gaskets for the squawker inspect the wires from the network to the drivers and replace if dodgy

I used Rustoleum Painter's Touch 2X Paint & Primer spray paint. I found the satin "canyon black" colour to be just right.

@Bacek I have updated the measurements I made about the Aiyima A07. It might be of interest to you. As you'll recall I'm driving my tri-amped La Scalas with three A07s (1 for the tweeters, 1 for the squawkers, and 1 for the woofers). Here's the post.

Typically I listen at around 80-85 dB(C). At those levels I don’t hear any noise at my MLP (which is about 4m/13’ from the speaker). At lower levels, I don’t hear any noise at the mouth of the speaker, even with nothing playing. However, if I turn the gain up high I will hear a hiss. YMMV, of course.

I’m running a similar config (tri-amped La Scalas with 3 Aiyima A07 amps — one for tweeters, one for squawkers, and one for woofers). Using the stock power supplies I am unable to hear any noise. I did hear noise when I tried to consolidate the three power supplies with a Meanwell LRS 600-36, so I went back to the stock power supplies. I’m very happy with how my system sounds. The level of noise is at least as good (perhaps better) than the Yamaha R-N803 I was using before I tri-amped the speakers.

Agreed.

Why? Both 4 ohm and 8 ohm are “nominal” values and the actual impedance will span quite a range. Unless one is running the amp at its maximum (never a good idea) it shouldn’t be harmful.

Impedance changes with frequency. An 8 ohm rating is a nominal figure — the actual impedance can vary significantly over the frequency range by quite a lot. Some crossovers (networks) try to normalize the impedance presented by a speaker but most don’t. Consider the K-33E woofer used in La Scala. Its impedance ranges from about 4 ohms (at around 150 Hz) to around 27 ohms (at around 45 Hz). The DCR (DC resistance) measures just under 4 ohms, but that’s a resistance figure, not impedance. Some time ago, the late (and much missed) DJK posted information that “the measured magnitude of impedance which the lipschorn presents to an amplifier … The lowest value within the audio range is 4.5 ohms and occurs at 55 Hz, while the highest value is almost 10x that amount, 42.3 ohms at 2155 Hz.” Even so, the Klipschorn is rated at 8 ohms. All amps — both tube and SS — will adjust (within reason) to the differing impedance presented by the speaker. However, tube amps may struggle to push around the low impedances more than SS. Unless you’re pushing the limits of your system, you should feel free to experiment with different impedance taps. You might try one speaker on one tap and the other on a different tap for testing. Dave

+1 on using a MiniDSP 2x4HD (or similar DSP) when dealing with multiple subs. The subs can be dialled in using measurements from REW and analysis from MSO (Multi-Sub Optimizer). The resulting configuration (delays, gain, PEQs) can be exported from REW right into the MiniDSP 2x4HD. Both REW and MSO are superb pieces of shareware/freeware.

Two 1983 Heresy 1 fit easily in a 2010 Mazda 3

Two 1986 La Scalas fit nicely in a 2017 Ford Escape

Yes. Make note of what is connected to what when you unhook the AL. Then simply connect the AL3 the same way.

Capacitors can deteriorate with age. A common symptom of a bad capacitor would be if it leaks or if the case is bulging. Other components, such as inductors tend not to be affected by the passage of time. Consequently, it is common to have to replace capacitors on older crossovers. Good capacitors can be had from many sources. @001 is a proponent of ones sold by JEM, but less expensive caps and caps with better specs are available.