DrTUBE

IMHO, it's certainly not a bad investment, @MacWorks... Well, only 10Watts RMS coming from a pair of EL34 in a Dynaco MKII amp is somewhat curious... That said, I drive my HERESY I HBR with a pair of compact 10Watts DIY OTL monoblocks, and it is way enough to reach an unbearable loudness level ! So with your "reputedly" MKII 10W Dynacos, it should work fine... Maybe the power tubes are connected in triode mode ? Cheers,

Today afternoon, being alone at home, I could test my "fully stuffed" HERESY I at high loudness - relative to my small auditorium, of course - using the amplifiers that I designed among others for them : These are OTL (Output Transformer Less) mono block amplifiers, able to give continuous 10W RMS @16R, with a 1Hz-200KHz bandwith @10W. I can confirm that - considering the means implemented here - the result with "full stuffing" is rather satisfactory, in terms of box resonances cancellation in the low-mid / mid region, which tended to be "ahead" of the rest of the sound spectrum, overshadowing notably the bass extension offered by the OTL circuit. Another benefit provided by the full stuffing is the lowering of the Qtc of the enclosure, which improve the bass extension (not the level) and the transient response. That said, I'll have to make some measurements to check that effective Qtc lowering... I remember that in 2005, I measured a Qtc at circa 0.8 , the enclosure being factory stock, but I am unsure of the value, since I did not retrieved my notes... One of you knows the Qtc value of the Heresy I, by chance ? Cheers,

Thanks @yamahaSHO ! Well, seen at distance, they look good... But when you come close... Cheers,

@billybob: On the web, I found this document below, called KLIPSCH HERITAGE REFERENCE DATA - (V.3 - 23 Aug 2013) https://2d73e25b29782b6d6766-9c8af5cbfef16739445bc76457060528.ssl.cf2.rackcdn.com/Codex_V3_130823_635128700889860000.pdf Where there is many useful informations about codes used by Klipsch. Well - you may already know it, I guess, but anyway it's not bad to share it... Cheers,

OK - I see @ClaudeJ1 and @MookieStl ! In fact, "Bass-Reflex-ing" my Heresy I was just an experimentation I did in the mid-2000s... Today, I consider letting them in Sealed enclosure operation definetly. For a Bass-Reflex, I would go differently. By the way, I have read somewhere that Klipsch "recommends the K-24-E as the replacement woofer for the K-22-K" that I have in my Heresy I. Is that a true statement ? To your knowledge, Is there other alternatives ? Cheers,

Ah, OK @ClaudeJ1 - I see,... Thanks ! Cheers,

Ah... Maybe one day I'll have a pair of Chorus I... An follow this path too ! Cheers,

Last update - after another coat of tint... ... Far from being premium, indeed, but considering the original damages, it's not worse... So let's say that's enough and "acceptable by default". End of the affair ! Cheers,

@TexDrone : It seems that it is Fir plywood, covered with a thin Birch veneer, according to the answer of members in your dedicated topic on the subject. @yamahaSHO : Unlike your nice work, my attempt for a refinish of the edges of my Heresy I HBR ends to be very far from remarkable... - The hardwood sealant is not so hard, and doesn't absorb the tint as expected... - The poor wood itself reacts unevenly in absorbing the tint... OK... I will pass a second - and maybe a third - coat of color locally, hoping that the result will improve and be more tint-even between edges and faces, and... Basta ! It's useless to waste my time to go further with those cabinets, IMHO. If I want a nice finish, I just have to build a pair of cabs from Beech glued-laminated timber, like my small "Cubes" below : Cheers,

@ClaudeJ1 : I attempted to search on the forum but found no traces of those Super Heresy 3.0 by Fido... Can you point me to the link ? Thanks & Cheers,

Ah, OK - I see... Thank you Guys for all your informations & tips - I record them ! Cheers,

OK - I see... Thanks @billybob Cheers,

Guys : the letter designation in Klipsch enclosure names, labelled "type" : what does it means ? I saw Klispsch Cornwall type CWO, CBR, CDBR and Heresy HWO, HDBR, my Heresy I are type HBR... Any of you have the key to this code, or is willing to direct me to the matching information source ? Thanks in advance & Cheers,

OK - I see. Thanks @Klipschguy ! Cheers,

Here's my contribution to the Vintage Stereo Receivers thread : Marantz 2015 and 2250b, bought 2nd hand cheap at a time where the Digital was focusing all the attention... Marantz 4240 - Even if it was profitable, I should NEVER have sold it... Again my 2250b and a Sony STR-6055 : OK - these ones are not Stereo, but they are nonetheless great sounding AM-FM receivers : Blaupunkt Riviera and Milano... Cheers,

Thanks @Klipschguy ! Question : I saw that the cabs of my Heresy I are assembled by outside nailing and internal stapled bracing in the angles. But do you know if in addition these cab panels were also factory glued ? Yes, I'm tempted to build a pair of Heresy cabinets using Laminated-Glued Beechwood. This wood is consistent to machine, mechanically resistant, and offers easily a nice natural finish just by oiling it - hence my small "The Cube" - where I used kitchen worktop oil : Cheers,

Hi @Klipschguy Here are the mentions found on my Heresy I HBR pair : They are also stamped "USA" : I noticed this today... I'd rather agree with @Dave A : it looks like Fir or Pine plywood, looking at the edges and the way it reacts under the radiusing bit of the router... Below : Upper cabs are made from laminated-glued Beechwood : hard and abuse resistant. Center cabs are mad from Pine plywood : quite resistant, but not not as good as Birch, indeed. Lower cabs are made from Fir wood planks, covered with tolex : tender like buter, poor resistance, but lightweight. Cheers,

God wanted to upgrade his Klipschorns, so he called Mr. Crites, on the insisting recommendations of a certain Mr.PWK... Thank you again Mr Crites for your useful help and top notch products when, in the early 2000s, I built my DIY Cornwall enclosures : Cheers,

Well @TexDrone, the only thing that I can tell about my Heresy I HBR is that the plywood is quite brittle... Even if I use a brand new router bit and I go slowly, radiusing the edges to eliminates bumps and cracks... Cheers,

Here is the calibrated impedance curve of one of my HERESY I HBR (S/N°=170Y006) factory stock, with her E-2 Xover : Cheers,

Thanks @henry4841 On the Ultimate 300B, the output transformers are from the French brand STS Millerioux (from mid-80s), model HH25-B. These are sealed, C-core, 2500R/4-8-16R/25Wrms. On the Ultimate OTL6080, what looks to be output transformers (black casings) are in fact the power stage filtering module. As this amp is an OTL circuit, there's no output transformer : Cheers,

OK, I see - Thanks @yamahaSHO Unfotunately, the corners have been damaged in the past by schocks / bumps, probably due to mishandling or falls : the wood has been crushed and just brittled under the router bit, so there's no matching part to reglue. A hard filler repair will be required. Cheers,

I browsed the entire topic and saw an array of nice tube amps, both DIY and commercial products... Consquently, I distributed so much "likes" that I have been "like-forbidden for today" by the forum platform (may be I have been considered as a "like" bot ?) I complete the thread by some of my DIY achievements - which share the same Hammond aluminium casing (1550J = 275x175x67mm) : Cheers,

@yamahaSHO I decided today to follow your path for refinishing my Heresy I ... I started by rounding the edges, just like you did on yours (below) : I guessed that you went for a 6mm / 1/4" radius because of the presence of the nails assembling the panels ? Well, it's what I was forced to use, by the way... You can also see that - converesely to yours - my Heresy cabs have been unfrotunately damaged (quite badly) by the previous owners at the edges (picture above and below) : My Makita RP0900 Router did her best with a brand new 6mm radius bit, but alas, it couldn't erase all the damages... I think I will have to use some wood filler here and there... Not so nice... So I have a few questions : 1 - Are the cabs panels of your Heresy I nailed, like on mine ? 2 - I assumed that you used a 6mm radius bit, but maybe it was 8mm ? 3 - it seems that my Heresy I have been some sort of stained and varnished, or was it an original finish option (designated by the term HBR) : what's your opinion ? 4 - did you performed some local wood repairs on your cabs ? Thanks to let me know, Cheers,

Thanks @AndreG. ! Yes indeed, bracing the back panel itself is easy, and I'll plan to do it also. Maybe by building a special braced panel... In the early 2000, I quiclky experimented a Bass-Reflex transformation of my Heresy I, by building a special ported back-panel : The performances obtained by software simulation were interesting, but proved not to be so convincing finally... It was a quick test that I did not dig further at that time - I should ! Cheers,