You could also get some alligator or mini-grabber adapter clips such as these and take a crappy RCA plug, strip it, and clip onto the shell of it. Many test lead sets come with an assortment of attachments. I use a set from Mueller that works pretty well and wasn't very expensive.

Heh, there's a tool for adjusting trimmer pots. Now I know they're called trimmer pots. I hate these tiny things.

Now I'm absolutely sure that the BHSE and Aristaeus were designed by a young person, probably around 25 or less. Hey, I can recall how I used to have keen eyesight and good coordination too.

Pars, I'm afraid you don't yet realize the extent of the ignorance and incompetence that you're dealing with. "Clip onto the shell of a crappy RCA plug?" I don't have a spare RCA plug lying around. "Test lead sets?"

How about an "audiophile-grade" holder for one of the multimeter probes, to act as ground? Maybe something shiny, chrome-plated, with a weighted base and perfectly shaped to cradle that probe and ensure excellent contact?

Currently playing: Boccherini - La Musica Notturna delle strade di Madrid from Tacet SACD "Die Rohre - The Tube." Wow, the smoothness! The excellent passacalle movement is played at the end of the movie Master and Commander.

I admit to enjoying some violins and other stringed instruments once in a while.

Heh, there's a tool for adjusting trimmer pots. Now I know they're called trimmer pots. I hate these tiny things.

Now I'm absolutely sure that the BHSE and Aristaeus were designed by a young person, probably around 25 or less. Hey, I can recall how I used to have keen eyesight and good coordination too.

Single turn trimmers are about the same size and impossible to actually set well once you get used to these they will be easy.

How about an "audiophile-grade" holder for one of the multimeter probes, to act as ground? Maybe something shiny, chrome-plated, with a weighted base and perfectly shaped to cradle that probe and ensure excellent contact?

If your meter has removable probes just get someone to make one that goes to ground on an RCA jack. If it dosnt have removable probes RCA ground to an alligator clip. Nice and simple.

You, sir, are the only nice human around here. You may have dibs on the ES-1.

I got a multimeter some time ago, after I got an SRM-T1W and Spritzer explained how to bias the tubes. Apparently it's the same way with the BHSE, which also involves sticking the probes into the Stax output jack.

I'm not a complete idiot. An incomplete one, sure, probably, especially when it comes to tube amps and I barely know how to use the multimeter. But I was already accustomed to removing the top cover of the Aristaeus to bias its tubes, and the SP ES-1 has convenient receptacles on each side to put the probes into and knobs to adjust. I expected something similar.

I looked at the top cover of the BHSE amp section and didn't see the four tiny small gold screws inside the holes next to the tube sockets. I did see the twelve allen hex screws and figured that they're not meant to be unscrewed on a regular basis, unlike the Aristaeus' four simple philips-head screws. So, if the top cover stays put, and I don't see any knobs to turn to adjust bias, I thought there isn't anything I could do. Out of sight, out of mind. And nobody said anything!

Anyway, that's my explanation. It took me an hour to think up, so I hope it's convincing.

Currently playing: Madonna - Like A Prayer (12" Extended Remix) Oldie but goodie!

Don't tell me everyone listens to sophisticated intelligentsia music! Classical and jazz, barf! I'll attend one of your meets secretly as an anonymous newbie and don't let me catch you with Britney, Beyonce, Leona Lewis, Rihanna, or other Top 40 on your playlists!

Very nice write up, except for one thing. You forgot Fergie!

.

Very nice write up, except for one thing. You forgot Fergie!

.

She's got humps

She's got humps

She's Fergilicious!

Now I'm absolutely sure that the BHSE and Aristaeus were designed by a young person, probably around 25 or less. Hey, I can recall how I used to have keen eyesight and good coordination too.

Yep once you turn 40 you are toast. They used to make tv alignment tools which

had a recessed blade inside a plastic tube. Put it over the pot and it stays in place.

various politically incorrect name for those tools.

Yep once you turn 40 you are toast. They used to make tv alignment tools which

had a recessed blade inside a plastic tube. Put it over the pot and it stays in place.

various politically incorrect name for those tools.

Bourns still makes one:

Beezar.com

Yep once you turn 40 you are toast. They used to make tv alignment tools which

had a recessed blade inside a plastic tube. Put it over the pot and it stays in place.

various politically incorrect name for those tools.

edit

marc beat me to it.

There are a number of these for sale at Mouser (for example, there are ones for the sealed trimmers, that require a different tool), here's one:

H-90 Bourns Potentiometer Tools & Hardware

Heh, there's a tool for adjusting trimmer pots. Now I know they're called trimmer pots. I hate these tiny things.

I included one in the box

I included one in the box

That is damn funny.

That is damn funny.

Needs to be wrangling an elephant.

My favorite post of the month for sure!

Hey, no being mean to fellow four-legged mammals!

I included one in the box

Yay! Yes, I have it!

So that's what it was. I thought it was some piece of junk that got accidentally left there. I should've known better, given HeadAmp's excellent reputation for attention to detail.

But it's beige-colored and says Vishay Spectrol on it. I want a black or silver one that says HeadAmp on it. Or maybe printed "Kevin Gilmore Loves You."

Given Justin's probable obsessiveness, and the fact that the stock tube boxes are individually labeled for the tube's position, I assume that the original biasing settings were set for the stock tubes. When I put in the stock tubes they were already correctly biased, and I thought they weren't bad!

So all the other tubes are actually better than I thought!

Edited August 26, 200916 yr by Elephas

You are welcome to think what you will.

Go ahead and make more rolleyes.

Given Justin's probable obsessiveness, and the fact that the stock tube boxes are individually labeled for the tube's position, I assume that the original biasing settings were set for the stock tubes. When I put in the stock tubes they were already correctly biased, and I thought they weren't bad!

Yes, the stock tubes are labeled by position and the bias is set correctly for them in those positions.

You are welcome to think what you will.

Go ahead and make more rolleyes.

Sorry Elephas, one more story that might make you feel better...

So the Zana Deux has those damper diodes in the back that take care of rectification. Well those damper diodes have plate caps, little pieces of wire that go from the top of the tube into little sockets in the chassis which is part of their normal operation.

Craig tells me about this guy who complained to him that the amp was running with the tubes showing their lighted filaments, but there was no sound. Also, the guy complained that when he touched the top of the tubes, he got a little shock.

Craig realized that he didn't even have the plate caps on top, but also figured out that the owner threw away those "little pieces" as he didn't think they were important.

har har.

Awesome I see death by tubes in that guys future

Yes, the stock tubes are labeled by position and the bias is set correctly for them in those positions.

I just now noticed this after reading your post. And given the few times that I've already removed & inserted the tubes, I have to assume I have them placed out of position by now. So does it matter much if the tubes aren't in their original positions now?

I have access to a multimeter but no idea how to check the bias of the tubes even after reading the previous page. If someone could provide steps of how a newbie can do it, I'd be most grateful.

I just now noticed this after reading your post. And given the few times that I've already removed & inserted the tubes, I have to assume I have them placed out of position by now. So does it matter much if the tubes aren't in their original positions now?

I did the same thing. In my haste to listen to the BHSE I just put the stock Mullard tubes in anywhere. It wasn't until I tried tube rolling that I noticed the tube boxes were labeled by position. New owners take note....

I just now noticed this after reading your post. And given the few times that I've already removed & inserted the tubes, I have to assume I have them placed out of position by now. So does it matter much if the tubes aren't in their original positions now?

I have access to a multimeter but no idea how to check the bias of the tubes even after reading the previous page. If someone could provide steps of how a newbie can do it, I'd be most grateful.

I'm sure Justin will chime in later but here is a short guide:

1: let the amp warm up for at least two hours (maybe more since I'm not sure when it is running at full temp)

2: place the probes of the multimeter between the + and - output for that channel (in the Stax socket seen here, red in the + output, black in the -) and adjust the back pot for 0VDC.

3: Now remove the black probe and connect it to the shell of a RCA socket on the back (aka ground) and adjust the front pot for 0VDC.

4: Repeat for the other channel.

Lordy. If I messed mine up, they're going to stay messed up. I have no idea what you're talking about.

So, I've now spent some good time with this amp, and with both the APL Phillips I got from tkam and the Exemplar Denon. Right now I'm preferring the Phillips with the O2s, with the Exemplar having a ever so slightly softer tone, which makes the headphones seem a bit too polite for much of what I'm listening to right now. I'm pretty excited with what I'm hearing, and I get totally immersed in just listening. The only problem I'm now having is with the O2s. I might have to replace the headband. It really is too loose for my head, and I'm holding the cups to my ears to get the best sound, and that's no fun. I'd mangled the headband into a shape that kinda fit before, but after taking them to CanJam, the big noggin people stretched it out again.