TubesGlo

Just another ST-70...but I like it.

Last year I picked up a ST-70 in great condition from the owner of my local electronics repair shop for less than 400.00. It had a set of Dynaco Mullard EL34 xf2's that test strong and pretty evenly matched on a MaxiMatcher II, probably worth as much as the amp. I immediately installed a new factory style board from Dynakitparts as well as a quad cap can, choke, bias upgrade with balance feature, replaced se rectifier with diode etc. I have original good testing RCA black plate 7199's so went with original board with option for adapters. When the tubes were tested I was told they'd probably outlive me but I started playing with current production EL34's in hopes of finding one close in sound to the originals to alternate and maybe preserve my Mullard's. First I tried the New Sensor Mullard's which didn't cut it and after testing all the rest ended up selling them. A friend loaned me his JJ's and EH EL34's. No go on the JJ and the EH were identical to the New Sensor Mullard. Now here's the surprise. I installed a set of Groove Tubes EL34M and was impressed. First off they all tested within 3% plate current, hold a steady bias and sound so close in every way to the original Mullard's that anyone would be hard pressed to distinguish between the two. I'm not sure how long they'll last but as a stand in for my originals they'll do just fine. I've since had Sheguang EL34A and TAD EL34M loaned by a friend. The TAD and Groove Tubes appear to be identical from the same Sheguang production line. The funny thing after all this is that with the 3 or 4 sets of NOS driver tubes, 6gh8a and 6u8a, the 7199 sounds the best and those differences are more distinguishable than those of the EL34's. My Cornscala's resolve more than any other speaker I've heard so perhaps as subjective as all this may be these speakers are able to disclose nuances that otherwise may have been hidden. The old tubes be they Mullard or your favorite flavor are in a league of their own. Good ones are obviously hard to come by and very expensive. As a second string sub for my Mullard's, the Groove Tube EL34M and TAD EL34M (same tube) do the best job of those I've played with in imitating the classic Mullard EL34 sound. Genalex Gold Lion KT77 and the new Psvane although highly regarded are priced too close to vintage tubes for me to have any interest in. All subjective and just my opinion.

The final touch arrived in the mail today...

Yes, in my case it came down to cost. I wanted the genuine Cornwall IV but just couldn't swing it. I gambled and built these instead. I never heard Cornwalls in my own room so I don't know how these actually compare but I'm very happy and satisfied with the results.

Knowing early Cornwalls were lightly dampened with material that wasn't dense I used a paper-cotton blended absorbent material our lab uses at work. It does the job. I used an adhesive backed rubberized window and door flashing to dampen the horns.. It's a Crites style B build. 120 tweeter, 405 driver (JBL), M2380 horn and Crites 1526 woofer (Eminence). Stock Crites 500/5000 crossover. I used Premium 3/4 Baltic Birch with 3/4 poplar bracing. They're heavy and solid, glued and screwed with Titebond 3. I'm not hearing any cabinet resonance being introduced.

The Baltic Birch finish was pristine so I stained them as is. The color I chose is dark enough that you don't notice the unfinished edges. If you're in the Cape Cod area you're welcome to have a listen.

UPDATE: It hasn't even been a week and I am totally convinced these speakers were the best option for me. I was skeptical going in because I really wanted genuine Klipsch Heritage Cornwalls. I never heard Crites "Cornscala's" and bought in based on opinions and reviews of others. They are of course larger than what they replaced and they do everything in a bigger way. Huge soundstage with realism and detail at all volume levels, effortless with no strain. I've read comments stating bass can be lacking? I would say something else in the system is lacking if thats the perception. The listening space is critical to the experience. Even my dedicated room could be bigger but it is tight and treated. Rectangular at 14x20 with one door, no windows, isolated from living space. I love what these speakers are doing for my music and I loved the speakers they replaced, something I thought I'd never do. Powered by a modest completely overhauled ST-70 with a stock style replacement circuit board running old Mullard EL34's XF2, there is a sweetness along with authoritive dynamic power that draws you in to the musical presentation. Another satisfied Cornscala owner.

I stuck to the plans using all of Crites supplied components. Cabinets are of Baltic Birch. I'm no cabinet maker but they're all squared up, braced, glued and screwed tight. Most importantly, they sound awesome. Much better than I imagined, I'm very pleased.

Well here goes....Decision Made. At 57 I'm late to the tube experience and as much as I love my modified Hafler 500 I'm in love with the sound of my ST-70. I'm keeping it in the family so to speak anyway. Maybe the original Mullard xf2's that test like new along with the fresh new factory style circuit board and other components I replaced that breathed new life into this amp that sat idle for 40 years , just does it for me. This new experience sent me on the quest for Klipsch speakers knowing they could potentially be the perfect match. I knew I wanted a classic pair and discovered the Heritage series, specifically the Heresy IV which was the only new model in my budget. I sought out used but after auditioning the latest offerings I knew that if I purchased used I'd still be wanting the newer version down the road. Heresy sounded great but I wanted a bigger sound without subs. Forte sounded great too but the rear passive radiator presented a potential placement problem in my room. THEN ...I heard Cornwalls and wished I hadn't because that was the sound I wanted at the price I certainly couldn't afford. Even used their pricey and shipping ain't happening. I came to this forum and received great advice for which I'm very appreciative. I was ready to pull the trigger on Heresy IVs at 2200 shipped free, B stock. Thought I could resell them eventually easy enough and upgrade when feasible. I wanted that Klipsch sound and NOW...the impatient fool that I am. I knew the Cornwalls could be my last pair of speakers and I'd be totally cool with that . I couldn't spend 6500 but I could spend that 2200 for the Heresy's OR.....for less than 2000 buy what I needed from Crites and build Cornscala's type B. I ordered the kit yesterday and bought the Baltic Birch shortly after. Starting to cut the panels tomorrow and the kit arrives Friday. Not Klipsch but a tribute. Some will hate and I understand. I really did want the genuine artifact but I just couldn't swing the expense and wouldn't have been happy with anything that wasn't very close to the Cornwall sound. Here is a picture of their new home, room 14w x 20d. Boxed mains for the theater are recessed in wall to left and right of screen...sliding the new 2ch speakers out to the walls when watching a movie will be my weekly exercise. Thank you one and all and I'm sorry if any are offended ....I did come here seeking advice on Klipsch and came across this Cornscala concept at the end of the journey Regards, Jim

If I could find used Cornwalls at a good price, yes I'd go for them. I figure I can see how I like the Heresy and get used to the Klipsch sound. I'll keep an eye out for Cornwalls and if the right deal comes along, sell off the Heresy's.

See my last post on page 2

To get my feet wet in Klipsch waters I may end up with a pair of Heresy's shipped free at a reasonable price. Unfinished birch, Serial# on one is 8871356. Heresy II , 1988 week 7 ? Is 6-700 for the pair reasonable for all original in good shape? I know bargain hunters may say wait but I'm not seeing them for any less than that in the last month anywhere. Looks like the Forte's I was considering isn't happening.

That would be great, Thanks

You'll laugh at this...had the Road King for 1 year and traded it for a new Indian Chief Vintage....based solely on looks. Still have it and seriously looking at a Street Glide now. That decision will be more difficult than choosing my next speakers.

Yeah, I've too often made purchases only wishing I'd stepped up for what I knew I really wanted but didn't want to spend the extra money on at the time. This was especially the case when I bought a Dyna and should've gone for the Road King which I did 10 years later 🤔

So I drove over 2 hrs each way to the nearest Heritage dealer. They have all IV series on display.. I listened to Heresy's and if I stopped there I would've been content. Next listened to Forte and finally Cornwalls which are wonderful but way above my budget. The Forte sounds like a great compromise between the two with the extra depth in the lower registers that would negate the need for a subwoofer as I feel the Heresy may need but maybe not. There's actually a used pair of Forte II's in good shape near me which would cost 25% of new and I'd be happy with that even if I had to put money into crossover upgrades. Any thoughts on Forte II and their fit with my room and gear? Thanks

I'd snag a pair at that price but no one wants to ship these. I live in MA. and nothing around here.

Heresy is in my budget new, Cornwall would be used. I wouldn't be opposed to used Heresy II or III for that matter.

I need help deciding on my first Klipsch speakers. I've never heard anything vintage or in the Heritage series. My current towers were custom built by Source Technologies, are 3-way 8" woofer, 7" Seas mid bass driver and 1" silk dome tweet, 90db sensitivity. I've run them 20 years with a tube preamp and a modified Hafler 500. I recently overhauled a Dynakit ST-70 with a new replacement factory style circuit board and use the original Mullard EL34's which test like new. I have no desire to go back to solid state. System is detailed, dynamic and a great pleasure to listen to. I have a dedicated, acoustically treated listening room 14' wide x 22' deep, 8' ceilings. Speakers are 3' off back wall and centered 3.5' off side walls. Seating position is centered 8' from speakers. I can't sit further back because my drum kit is on a riser behind me. I listen to jazz primarily for upwards of 2 hours almost every night at moderate to slightly higher but not concert levels, roughly 70-85db average. I don't know if I would ever have considered Klipsch prior to owning a tube amp because I always thought in critical hi-fi listening they were best suited for tubes. I'm interested in the upper end, either Heresy or Cornwall. I have no dealers anywhere close to me that carry these so I'm reaching out for recommendations based on my equipment, room and musical taste. I don't want my speakers to sound like a PA system only suitable for extreme high volume, party levels. I want detail, smooth rich mids, high frequencies not harsh or sharp and full clean bass. I know Heresy's don't produce the lowest of frequencies but I think they'd be low enough for me. After updating my amp with a new quad cap can and better caps on the new board my bass response is plenty deep and tight. I appreciate any of you that own either of these speakers with similar gear helping me make an informed decision. Thank You