Avalon 747sp inside pics posted

[trock]

Since some of you really seemed interedted in the avalon 747 pics i thought i would start a quick new post to let you know they are up now at

http://groupdiy.twin-x.com/index.php

if you need more please let me know what you need, i have the M5 too but there is a stripped screw right now holding itinto the rack, once i get it out i will post pics.

the 747 is VERY heavy and hard to un rack and re rack so if you want more pics please try and get me all your requests at once since i only want to take it back out one more time


thanks

 

[CJ]

Great Trock! More than I expected to see in there.
Can you get a pic of the underside?
cj

 

[tubejay]

Wow, what's the deal with that MASSIVE power transformer??

 

[trock]

yep

once i get all the requests i will take them all at once and post, so far i have

1) for underneath
2) i will post the back also

i have to log off now, but will check back with all of yo utomorrow and give it till this weekend and then i will try and get it all deon and the m5 over the weekend and put them all up?

how does that sound?

 

[SonsOfThunder]

:sad:

Can't get this page to load!

Wanna see it!!

 

[rich]

Maybe there are no transformers, I talked to the owner of Avalon once and he said that the goal with that pre was to keep costs down. He sure knows how to build stuff.

 

[jensenmann]

Thanx, Trock :thumb: :thumb: :thumb:
Can you get us some close ups? It would be very interesting to see(read) more details.
Man, I´m hot for this M5
cheers
Jens
:guinness: :guinness: :guinness:

 

[gyraf]

Thanks for the pics!

There sure is a lot of stuff in there - but only three tubes..? They look kinda sad and alone over in that corner..

:grin:

Jakob E.

 

[Guest]

From the spec sheet...
Circuit topology Three (3) dual triode vacuum tubes (Sovtek 6922), high-voltage discrete Class A mode.
TSP (twin signal path) which gives you the choice of either tube tone or the classic, Class A discrete transistor sound by exchanging, three (3) high-voltage dual triode tubes with discrete amplifiers in the opto-compressor and primary output stages.

Fully balanced Class A input and DC coupled outputs
Input gain range Balanced, Class A, 20k ohms, -20dB to +16dB with high gain switch

Maximum input level +36dB balanced XLR pin 2 hot
Maximum output level +30dB balanced 600 ohms, DC coupled, discrete Class A

Compressor type - optical attenuator acts as a passive level controller with a Class A, variable gain make-up amplifier.

Equalizer type Discrete Class A, passive design optimized for full range program material
100% discrete, Class A high-voltage transistors

On transformers - according to Fletcher
http://groups.google.co.uk/groups?hl=en&lr=&threadm=37FC84C8.366%40mercenary.com&rnum=1&prev=/groups%3Fq%3Davalon%2520747%2520transformer%26hl%3Den%26lr%3D%26sa%3DN%26tab%3Dwg
There aren't any

 

[trock]

Hey Guys

Since i have a few pics as an "overview" if i started some real close one i take it you all would be able to figure out where that pic is based on the overall??

so i will take some underneath, back and sides, and then a bunch of the insides close up??


how does that sound?

and the m5 once i get it out of the rack, may try to drill it out tonight

let me know

 

[trock]

Hey i see the post above me mention Fletcher

i have been talking to him fro a while from another recording forum and it is really nice and helpful to me, even when some others weren't

anyway, i only know him as fletcher and that he works with or at Mercenary and does this for a living??

does anyone know him?? or has met him?? he seems to turn up all over the place and people seem to really respect him

thanks

 

[tubejay]

On the 737sp the audio transformer would be in the upper left, and I'm pretty sure it's a lundahl. I'm not sure if they only have a mic input transformer in the 737 or not. The 747 doesn't have the mic pre, right? I'll open up my 737 to get a look at the transformer type. I'll try to take a pic too.

 

[trock]

Hey Tube

the 747 is only a Comp and EQ

i use the M5 for my pre

 

[tubejay]

The funny thing is that the only thing I use my 737 for is the mic pre!!! I can't get that damn compressor to do anything pleasing for me. The eq has it's nice points though. I really should just sell this and buy an M5. I love the sound of the mic pre on this thing, especially when you overdrive it a little.

 

[tubejay]

Here's the 737sp inside. My understanding is that this had a better mic input transformer than the original. I don't know if that's true or not.

This transformer has to be a lundahl, right?

 

[tubejay]

Here's the EQ a little closer. It's got a layer below it (and I'm not going to even mess with that) but hopefully this should help. It kind of looks like the low eq is on the left pcb card, and the mid and high is on the bigger right card. It's hard to say for sure though.

 

[tubejay]

Are those blue silverish round BC caps electorlytics?? They appear to be labeled like electros, but they just look so different from the caps I'm used to seeing.

I had already taken pictures of the EQ section...so it only took a second to post them. :wink:

 

[Bauman]

so any good soul can ´study´ this mike pre ?? :green:

 

[verbos]

[quote author="buttachunk"]am i missing transformers ???? where are they ?

also, what opamps are those quads and 8 pin packages ?


i spy 3 vactrols :green:[/quote]


well I can't help you with the 8 pin guys, but the quads are LF347N I can read that in the picture. They are quad J-FET opamps. I haven't ever tried those out, but I bet they are very similar to a TL084.

The 3 vactrols are for 2 channels and a meter.

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