Glenn Studio Amplifiers

@2359Glenn currently builds three types of headphone amplifiers:

1. An OTL
2. An EL3N amp
3. A 300B amp

I've asked that he provide me with specifications and prices for each of these amps in their standard configuration. Once he responds I'll add this info here.

Here are images of a few builds.

 

Glenn will be building me an OTL with the following features and parts:

Power tubes - 6 x 6BL7 or 4 x 6AS7G or 2 x 6336
Drivers - C3g
Quasi dual mono power supply with Lundahl transformer
Clarity Cap TC600 440 uF output capacitors and in power supply
Khozmo shunt attenuator with 48 steps
Jupiter copper PIO interstage caps
Pre-amp functionality

 

Cool topic. How long have you been in line for your upcoming OTL? I should contact Glenn to see where I'm sitting, as got in the queue about a year ago. In a couple days, when I have some free time, I'll post some impressions of the earlier build OTL (with some interesting customizations) that I purchased used. For the moment, I'll just say that I'm thrilled with Glenn's OTL and feel it's a truly incredible value.

 

Impressive parts selection. Sounds like the makings of some really solid gear

 

Will probably be the amp I upgrade to from Valhalla 2. Glenn said that the base OTL amp pushes about 2W at 300ohms.

Head-Fi thread for reference: 2359glenn | studio

 

I have an earlier and more basic version of the Glenn OTL with 5 volt rectifier, two 6AS7 or 6336, one 6SN7 (with a 6/12/25 volt heater switch) and two C3g. A great amp.

 

I'd like a Glenn with 6 x 6BL7s.

 

I am more of a tube collector and tinker than an audiophile. And I am perfectly content with streaming Google Music through an Audio-gd Digital Interface - USB to Coaxial - to a Audio-gd Fun used as a DAC/preamp. My headphone is a slightly modded (Tak's filter-paper) HD700,

The Glenn is the basic stock amp with the addition of C3g sockets and the ability to select 6/12/25 volt heaters for the 6SN7 socket.

Glenn OTL with a Cossor 53KU, Cetron 6336 and a Raytheon 5694



Cossor 53KU, GEC 6AS7G and Siemens C3g (flat-black embossed metal shields)

 

I too am in queue for one of Glenn's OTL almost similar to OP's specs except I don't know which driver Glenn is planning for my amp. Eversince I have heard Punit's Glenn OTL amp with my own HD800, I knew I needed to get one for myself. Hopefully, mine is next in line.

 

If you are leaving it up to him, and you are asking for the best sound for the money, I would guess he will select the C3g. However, my goal was slightly different. I wanted to have an ultimate tube rolling amp. So I specifically requested one octal double-triode socket and two loctal C3g sockets. Moreover, I wanted to be able to run 12 and 25 volt tubes as well. For example, this blue beauty is a 12 volt FDD20 manufactured by Philips in their Milan, Italy, factory during WWII.

 

That's good to hear gibosi. I don't have much time to tube roll so I will keep the basic config once received.

 

lukeap69

I have a 300B amp then MoatsArt's amp then I can build yours.
six 6BL7s for outputs

 

Welcome to SBAF Glenn. Thanks for the update.

 

lukeap69

Six 6BL7's? That will be great! Adding four more output sockets is the only thing I would change about mine if I could....

 

Hi Gibosi

What will be the benefit of adding more output sockets?

Arnold

 

Many believe that the 6BL7 sounds better than the 6AS7. However, the 6BL7 isn't as powerful as the 6AS7. so it takes a bunch of them. So this configuration gives you the ability to use six 6BL7, three per channel, or even four 6AS7, two per channel, as output tubes. An added benefit is the ability to drive low-Z cans with ease.

You might find this posting interesting:

http://www.tweak-fi.com/apps/blog/s...nce-system-part-2-glenn-s-headphone-amplifier

 

I see. Glenn told me the amp he will build for me can also run 4 6AS7 for low Z cans, so it seems I will have that option already.

 

Looks like you're getting the amp I'd want. I'm one of the folks who thinks the 6BL7 is a superior sounding tube. ATM, it's either a pair of 6BL7s in the Elise or a single in the Darkvoice. Neither config has enough power for anything aside from late night listening, but 3 of the tubes per channel paralleled should definitely do the trick. And the sound, OMG! I'm truly envious of the amp you'll have.

 

Even with only two output sockets, like my amp, you can run a pair of 6336 for low-Z cans. Your amp will give you more options. With six output sockets, you will be able to use one pair of 6336, two pairs of 6AS7 or three pairs of 6BL7 for low-Z cans.

 

@Shaffer @gibosi

Thanks. This just makes the waiting more difficult.
I was also following the Elise during its development and almost purchase it except the lack of impressions for the HD800 pairing did put me on the backfoot. Eventually, having the chance to listen to one of Glenn's OTL with my own HD800 made me decide to ask Glenn to build one for me.