Suhr Corso | A Tricky Problem and a Look Inside

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[@mattroberts4201]

Thank you for making me laugh in the first 18 secs of your intro. Witty and knowledgeable.😁

[@tyler3705]

Love the content. Just an FYI, as a sheet metal fabricator, that chassis looks like it's a bent box rather than machined. I can see the welds in the corners and it looks like the top face has been welded and ground smooth. Most likely laser cut from a sheet, pems inserted, bent then welded. If its aluminum (which is looks like), it could probably be made domestically for around $8-15 depending on the size of the run.

[@PsionicAudio]

Cool, thanks. I know Suhr machines some aluminum stuff out of billets. This chassis is so much more put-together than most out there - it's really nice.

[@thesoundpurist]

10:00 I'm always stunt how John find to come out with a great amp every time

[@scottwilcox6313]

I won't mind having an Eames chair and that cool little amp in the studio. Man, Suhr makes just quality stuff.

[@pwlebrun4573]

I bought one of these recently (serial # 0004) when I was in the market for a low-wattage tube amp, preferably with power scaling. I was leaning toward the Blackstar 5W head, or maybe a Blues Jr or the Supro (Delta King?). But luckily I started watching Lyle’s videos, and learned why the latter were less than ideal, and why patiently stalking Reverb for a Corso would be worth the money. I’m assuming such a story is one of the reasons why you started your channel. If so, mission accomplished.

[@PsionicAudio]

Thanks man! That indeed makes me happy to read. I’ve always intended these videos to help musicians understand amps and make more informed decisions.

[@jc.1191]

@@PsionicAudio It's helping me as well. Thanks for sharing.

[@alexwoolridge94aw]

His channel has helped me as well. Every guitarist should be subscribed to psionic audio

[@kennethlinton4432]

Love this site. Found it by accident too. So MUCH better than the marketing nonsense produced by the magazines. I did NOT buy a Marshall SV20 as a result. Sure/Friedman for me.

[@stratfanstl]

Nice sounding amp. I like how "linear" it was both in the crunch and bass/treble realms. Rather than being limited to very narrow (hard to find) ranges across different controls, this design provides wide ranges where the control being changed made noticeable differences in the tone while sounding good across the whole range. Seems rare these days.

[@samright4661]

That Amp sounds Killer ! I’m impressed. It was clever ,putting the PCB board on the Bottom of the Amp . Great Design

[@pomegranitejason]

I have the confessional grille version, i took the weird handle off, (it's rigid, doesn't "kneel") The only way to do an effects loop is by way of a n "OX Box load box setup. I couldn't take that shell off either, BTW this is a phenomenal amp, recording, jamming or even live with a slave amp. The ONLY issue I have is the attenuator is just a wire mesh resistor type and it's really trigger happy, it jumps from 0 to 5 with a couple of mm movement. It gets a bit better when you whip it around a couple of dozen times.

[@richardlynch5632]

Cool little amp. Another well made amp that can be added to the list of amps worth my attention/money. Thanks Lyle😃👍 Nice detective work😎👍

[@synonyx]

Thanks for the deep dive! I own a Corso and from the day I brought it home it's always impressed me. John himself told me they canceled it due to low sales. Surprisingly now anytime they pop-up on reverb for sale in the states they are gone within hours!

[@SergeiVlassov]

Mine was for over a year on a Reverb, for 750 EUR, in mint conditions, and still not sold (now temporary taken down, want to play with it a bit more)

[@jerrymckenzie1858]

I have amps by Suhr, Bad Cat, Blackstar, Marshall and Fender. If I could only keep one (for recording) it would be the Corso - no contest. It sounds great and it's extremely versatile.

[@David888B]

Been interested on one of these, good timing.

[@youropionmattersnot]

Love the channel. I am always surprised and not in a good way, at how many of these high priced boutique amps use circuit boards. I picked up a used Goodsell combo for $1000 and it is all point to point hardwired. No circuit boards, no integrated circuits just wires, diodes, resistors etc. I've had to have one repair performed on it in 8 years and this amp gets worked hard. Acorn amps in Atlanta completed the repair in under two days replacing two output resistors and fresh power amp tubes. "I love working on amps built like this" is what the tech said.

[@diegorhoenisch62]

I, on the other hand, continue to accept as normal(tragic, but normal) the percentage of people who feel comfortable expressing their opinions about topics of which they understand very little. There are truly shitty amps that are wired point-to-point, and there are truly great(e.g. the Suhr Corso) amps that use circuit boards. Cheers, Alan Tomlinson

[@JEmilioJNava]

good sounding amp, thanks for the bench showcase

[@Ryan-gb6gb]

Lyle I love your channel. I'm a harmonica player. I use a harp gear 5o watt amp. Thank you for what you do. It's very interesting.

[@elambassist]

Thank you for your service.

[@user-tx8uc3iw3w]

More good work from John Shur and more good work from Psionic Audio 😎 🎸 🇮🇪

[@benlogan430]

I always enjoy furniture with a name!

[@johnwilliamson467]

First time I have seen 12BH7a used as outputs given it a strong 12au7 more current about same gain .Seen them used as driver tubes since the mid 50's like a 6sn7 or 6cg7 has been used.

[@alecboyyes]

Blackstar HT5 uses a single 12BH7 as power tube, think the H&K Tubemeister did as well. More recently, Laney's low watt LA Studio amp uses one as well. This is the only amp I have seen thus far that uses two of them in the power section though.

[@johnwilliamson467]

@@alecboyyes well it does work just not what I would use in a small power tube . little pentodes el84, el86 or 6080 for a triode .

[@roncarter2188]

I tried one of these out at GC a couple years ago and thought that It was a really nice sounding and versatile amplifier for the lunchbox type amps, nice video.

[@luthiervandros]

Beautiful sounding amp

[@sgt.grinch3299]

Sounds like a quality investment to me.

[@batman9592]

Seems like a lot of tube rolling fun could be had with this little beaut.

[@dennisflock3958]

The Suhr-name! Awesome pun, especially if it wasn't intentional.

[@jeffmansfield914]

I came to say the same. 3:09, for any who missed it.

[@goodun2974]

This is the first time I've seen a preamp or driver type tube red-plate! Although the 12BH7's are actually being used as output tubes here, and therefore likely run at higher voltage and current than they would be if used as preamp/driver/phase-invertor tubes, but still....an unusual problem. Were those 12BH7 tubes actually modern production from Russia or China? Original US production are still around, since they were once made in large quantities for televisions, where they were used as vertical-deflection drivers and had to be rugged in order to swing high voltage pulses.

[@roscoepcoltrane23]

Suhr is good stuff.

[@donciseau]

Great video!

[@BCarpenter2314]

Great sounding amp!

[@youropionmattersnot]

Like the Madmen reference.

[@brianjones7521]

good video

[@zbaby82]

Nice sounding amp.

[@jephjacques]

Man Suhrs sound nice.

[@Joe-mz6dc]

Suhr is cool.

[@richardnagamitsu1582]

Lesson learned… keep your amps clean and check the tubes occasionally.

[@johndeschain2156]

Beautiful gut shot.

[@ctcards2636]

What ! ? Your not a cocktail host ? Damn! So disappointed you have no idea ! lol

[@thesoundpurist]

2:45 right at the beginning I thought of the tubes, especially because of the volume change

[@nicholasberndt6224]

2:50. You would have had a Suhr Riot on your hands? I get it!

[@jerryking2418]

Great job. Very unusual output stage. I wonder what inspired Suhr to use it.

[@alecboyyes]

There are a few contemporary low wattage amps that use 12BH7s in the power stage, Blackstar HT5 and H&K Tubemeister spring to mind, Laney have also adopted it for their LA Studio amp.

[@goodun2974]

@@alecboyyes there were several articles about DIY push-pull hifi amps using octal-based dual triodes published in radio-electroncs magazines in the mid to late 50's (can't remember the tube types offhand, but they were triodes designed for TV use). There are also builders who use BIG 6AS7/6060 octal-base dual triodes for audio (originally designed as voltage regulator tubes). They need 3-something amps at 6.3 volts just to heat them!

[@butchlauer]

Ìs it me or did someone just ask about Suhr? POOF! Your wish is granted.

[@TheLordcasio]

Sick burn!

[@infectionsman]

Lyle, I just fixed an amp that had an ultrasonic oscillation, without using a scope. Do you have any advice for using an o-scope for this kind of thing? I would definitely welcome a video of scoping for this kind of thing if you happen to come across an amp with an inaudible oscillation in the future.

[@BradsGuitarGarage]

I was just thinking it looks very Eames!

[@goodun2974]

I have a swiveling black leather recliner with footstool from the early 60's, using similarly steamed and bent plywood but stained to look like mahogany. It was my dad's; a little worn now, but comfy. Would have made a good set piece for "Mad Men", and worth several grand if in better condition nowadays.

[@maxine2798]

Kitchen drawer handle on top. A clever solution but it would annoy me!

[@goodun2974]

Thats not a rheostat, it's an L-pad, a speaker-level volume control that maintains roughly the same impedance load to the amp as the speaker itself, regardless of how you set the amount of attenuation. If you look inside an L-pad you'll find two wirewound resistance elements, both audio taper but one with an opposite resistance taper and wind compared to the other, so that as one increases the other decreases, keeping the resistance/impedance about the same throughout the control's rotation.

[@PsionicAudio]

I know, just didn’t want to go into it in the video as it wasn’t a problem.

[@goodun2974]

@@PsionicAudio , I figured you might know what an L-pad is, but offered the explanation for the benefit of anyone else who might not.

[@goodun2974]

@@PsionicAudio , did you ever find out the trick or procedure for getting the wooden case off?

[@PsionicAudio]

Nah, wasn’t needed. I’m sure it’s doable and I have the needed phone numbers, but it wasn’t a windmill that needed tilting.

[@PsionicAudio]

And I wasn’t lying when I said I was on my first cup of coffee in the early parts of the video. Post-noon me would have said L-pad and attenuation instead of power scaling.

[@tedmich]

Typical Suhr quality in a pretty little 5W box, these can be had for as low as $700 sometimes!

[@TheStimpy60]

Don Draper, lol

[@anthonycotto9251]

"Suhrname"

[@Walks-With-Pride]

I doubt I'll ever buy anything with the name Suhr on it. I'm simply not a fan.