New Here: Just Ordered Stereomour!

[InfernoSTi]

Grainger,

I understand what you are saying about caps: I think I'll focus more on tube rolling than cap rolling for a while.   I'm not certain you can really learn an amp until you have lived with it in a static state for some time.  One needs to be comfortable that you can hear subtleties and that just takes time.

Thank you for asking about the Hawthorne's.  These are an open baffle speaker that is purpose designed as such. The Hawthorne's are rated at 96db and are designed with low watt SET amps in mind.  They are often set up with either a single driver/tweeter combo or as a "duet" with an additional bass augmenter speaker or even as a "trio" with two additional bass augmenters.  Some recent experiments with five 10" bass augmenters has yielded very fast, detailed, and musical bass response for the handful of brave souls who have tried this set up.  Everyone tries their own baffle design and configuration.  Mine is a "1015 Duet" style.  I use a narrow top of the baffle to keep a fast mid and upper range, while I have a wider bottom to aid in bass response (with OB, you can "tune" the sound by the baffle shape/size).

My current setup is a 1" compression driver center firing through the cone section of a 10" mid-woofer.  This gives the benefits of both a crossover speaker (letting each driver handle the range it is good at) and the pinpoint detail of a full range speaker due to the unique configuration of the compression tweeter.  I also have 15" bass augmenters that I am bi-amping in true stereo with two Rythmik plate amps with a special OB "shelf" design.  I'm not an expert on the specifics but Rythmik worked hard to develop an OB version of their Servo plate amp.  Having these in stereo really adds to the imaging, particularly on drums and such.    

Front showing 10" and 15" drivers (CD tweeter center mounted in the cone of the 10"):
(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fwww.hawthorneaudio.com%2Fphotos%2Falbums%2Fuserpics%2F11473%2Fnormal_photo-211.JPG&hash=597c896dcea88bceaa39b8443dd32e79b64bde6f)

Back showing 10" and 15" drivers (CD tweeter center mounted in the cone of the 10") and remote crossover:
(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fwww.hawthorneaudio.com%2Fphotos%2Falbums%2Fuserpics%2F11473%2Fnormal_photo-212.JPG&hash=355a1e8f01a653cb475d73bc61845e6adab20be6)

in the left and right background, you can see the two plate amps:
(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fwww.hawthorneaudio.com%2Fphotos%2Falbums%2Fuserpics%2F11473%2Fnormal_photo-210.JPG&hash=0249f935d37252186381c3127af33ff34b489420)

Basically, I drive the compression tweeter and 10" mid-woofer with my SET amp and send a split signal via RCAs to each of my two Rythmik amps.  The idea is to maximize each of the strengths of the components to have as few compromises as possible.  There doesn't seem to be an end to how far folks can take this (and I'm just in the beginning of my OB journey).  The sound is a very present, highly detailed quality with lots of 3D soundstage.  Moving the speakers a bit can adjust the dipole delay to create more/less depth, which is really fun!

Here is a professional review of a set of Hawthorne "Duet" speakers:
http://www.positive-feedback.com/Issue31/hawthorne.htm

Hope that helps!

John

[Grainger49]

Wow, I got it now.  I have heard several open baffle designs, not this one.  Some were hits some misses.  I like the idea of the concentric drivers.  It would have to be a better arrangement, phase wise, than a design with all the drivers mounted to the front baffle.

[InfernoSTi]

Wow, I got it now.  I have heard several open baffle designs, not this one.  Some were hits some misses.  I like the idea of the concentric drivers.  It would have to be a better arrangement, phase wise, than all mounted to the front baffle.

Everyone is trying to find that "just right" sound for what they enjoy.  For me, these are the direction that "does it" for me. I get lost in the music in a way that I have never before.

Now about that Stereomour: tonight I put in the JJ 2A3-40s and JJ 12AT7.  I think I'm going to have a hard time rolling tubes as these seem to have the signature I love!  They are fast, detailed, and have crisp yet soft extended highs.  This amp with these tubes is blowing me away listening to Dire Straits "Dire Straits" on the new Japanese SACD.  I hate that I sound like a hyperbolist but I'm loving the Stereomour!

I have to give a plug to Eurotubes for their great price on the 2A3-40 ($210/matched pair)...thanks Bob!

https://ssl.eurotubes.com/cart/index.php?page=product_details&category_id=3&product_id=2A3-40-2

John

[InfernoSTi]

I just finished up a satin black case for my Stereomour. I had already painted the bell housing satin black.  Normally I do a wood stain but I asked Jeanine what she thought might be nice and she thought it would look good in black...I think she was right!   

John

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fwww.hawthorneaudio.com%2Fphotos%2Falbums%2Fuserpics%2F11473%2Fphoto-221.JPG&hash=70c73c59233c9f315f471440f1223150c45d7382)

[2wo]

I think she is right too. Pure classic...John

[InfernoSTi]

Thanks, John, you are right, the Stereomour is well suited for a classic look.

I have been itching to do a cap upgrade and finally did one last night and I'm really pleased with the results.  First, I took out the two 3.3uF Solen caps and replaced them with Auricaps in a "super cap" configuration consisting of the base 3.3uF Auricap bypassed with 0.33uF and 0.022uF Auricaps. Second, I bypassed the 0.1uF coupling caps with 0.022uF Auricap caps.

The improvements did have a very nice affect on the sound quality of the Stereomour 2A3: the overall clarity increased (i'm not sure if this is a tonal improvement or if the soundstage is being better handled, or perhaps both), the extension of the upper end was improved (cymbals have a longer "splash" decay), and the width and placement of the soundstage increased (minor improvements).

As I said, I'm very happy with the results which didn't change the overall sound of the amp as much as make things I liked about the amp a bit better!

This isn't the greatest photo as you can only see three of the four new caps, but it shows the general idea:
(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fwww.hawthorneaudio.com%2Fphotos%2Falbums%2Fuserpics%2F11473%2Fnormal_photo-222.JPG&hash=2f6379488e70ee7be9e2c07cd5b9eec16a9fccbd)

Thanks, John

[InfernoSTi]

Just thought I'd post an update: I've recently hooked up my Rega P1 with an Ortofon Blue cartridge and play it through my 2A3 and my Hawthorne Audio OB speakers (to which I've added a second pair of 15" giving four 15" woofers total plus the two 10" mids and the two compression horns).  Wow!  What a great combo for the price...lots of midrange bloom and just enough upper end extension/decay to sound great...and the bass is effortless bi-amping with two Rythmik amps plus the Stereomour 2A3.  Lovely with Dire Straits, Van Morrison, Dr. John, etc.

John

[InfernoSTi]

I've recently switched out the Auricaps for Mundorf Silver/Oil caps in the parafeed and coupling cap spots. 

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fwww.hawthorneaudio.com%2Fphotos%2Falbums%2Fuserpics%2F11473%2Fphoto-288.jpg&hash=6adbb54cd55feeffaff1b2f4a7785a4e1ba74ece)  (https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fwww.hawthorneaudio.com%2Fphotos%2Falbums%2Fuserpics%2F11473%2Fphoto-287.JPG&hash=45662a89ff911702dd20ac7f2f7cb6a9de106c8f)

I used the 2.7uF and 0.1uF caps, respectively.  They are significantly larger than the Auricaps but locating them was easy with the 0.1uF going below and in front and the 2.7uF going above and centered (a "hanging" cap location). 

The improvement is dramatic and well worth the $200 for the four caps.  Silky smooth upper end, detail across the entire range (the texture of the instruments is much more present, as well as the sound stage being smoother while maintaining detailed separation of instruments).  Finally, their is a more dynamic presence to the music (the bass sounds punchier and the horns have a more biting leading edge, for example).  The tone, texture, and dynamic nature of these caps is really a treat.  It makes listening very direct and creates a strong emotional connection to the music.  I couldn't be happier! 

I have to give credit to Ed (ebag4) for trying these out first and telling me how great they sounded to him....thank you, Ed!

John

[ebag4]

Hi John,
I am glad to hear you are enjoying the Mundorfs.  I have to tell you that those cute little caps are not big, these are big:

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fwww.hawthorneaudio.com%2Fphotos%2Falbums%2Fuserpics%2F10060%2FAmpOhm_Parafeed.JPG&hash=9e107742d21bb42c940a4588a29afd59a7a8c7f0)

And I thought you were from Texas?? ;-D

Best,
Ed

[Jim R.]

John,

Glad to hear you're enjoying the sio caps.  I can only imagine that setup you have sounds terrific.

Ed, are those the ampohm aluminum/poly/oil caps?  I've got a pair of those in 3.9 uF size for my stereomour though I may end up going with those in my FPIII+ and use something a bit smaller in the stereomour seeing aas the bass with the v-2s isn't going to be an issue.

Of course they may not fit nicely in the foreplay, so who knows.

-- Jim

[ebag4]

Hi Jim,
Yes, I put the AmpOhm 2.2uF Alum/Poly/Oil caps in place of the Obbligato cluster I had in the Parafeed Ckt.  I like the AmpOhms better than the Obbligatos in this circuit, they have given me a bit more "air" than I was getting with the Obbligatos.

Best,
Ed

[InfernoSTi]

Hahaha, Ed, yes, THOSE are real caps indeed! :-)     At first I thought you had photoshopped some beer cans into that photo....   I'm glad you are getting good results out of those monsters!

Jim, thank you...I didn't think the improvement would be so great...this is my first time with Mundorf silver/oil and I think I'm hooked!  Thank you for sharing your use of the AmpOhms, too...it sounds like you and Ed are thinking along the same lines (great minds, right?!!!).

I am going through an upgrade cycle and needed to improve my amp to the standards that the other improvements are (hoped to) going to set.  I am switching out the compression drivers on my speakers from the el-cheapo but very good sounding Eminence ASD1001 drivers and basic crossovers to a set of Radian 475PB drivers and upgraded crossovers (using Mundof caps and Alpha Core inductors, etc).  These are the Hawthorne Audio "Sterling" series compression drivers/crossovers.  I have already added a second set of 15" augmenter drivers so I have four 15" drivers handling everything under 100 Hz.  They sound amazing even at low volume (lots of effortless air movement).

The cap upgrade to the Stereomour is spot on for the direction I am trying to go with the system.  I wanted to get them installed and burned in before I made the switch to the Radians/Sterling crossovers so I could isolate each step rather than doing them all at once.  I have to say the improvements from the Mundorf caps in the amp are very satisfying even with the entry grade Eminence drivers.

John

[Grainger49]

I used the 2.7uF and 0.1uF caps, respectively.  They are significantly larger than the Auricaps but locating them was easy with the 0.1uF going below and in front and the 2.7uF going above and centered (a "hanging" cap location).  .  . 

John

Hi John,
I am glad to hear you are enjoying the Mundorfs.  I have to tell you that those cute little caps are not big, these are big:  .  .  . 

And I thought you were from Texas?? ;-D

Best,
Ed

John, Ed!  There is no use in arguing whose is/are bigger!

Sorry, I couldn't pass this up.

The higher the voltage rating and the larger the capacitance value the larger any design gets.  I'm impressed that the 1200V Mundorfs are that small.

Still, I like pictures of big caps.  Now it is your turn.

[InfernoSTi]

John, Ed!  There is no use in arguing whose is/are bigger!

Agreed.  And it isn't the size of the cap, it's what you do with it, right?  I've been practicing this line since high school and it STILL doesn't work!  Hahaha!!!!

Still, I like pictures of big caps.

Some people like to look, Grainger.  Quite natural and nothing to be ashamed of.... 

20 hours in and they sound great!  I've got Steely Dan "Gaucho" in 24/96 playing and it sounds like a million dollars!

John

[Jim R.]

John,

I'm sure you're going to be floored at the sound with the upgraded tweeters and crossovers.

I'm considering some 10" augies to put in an OB H-frame sub, though the temptation to go servo OB is pretty strong too.  These would be to augment my lowthers and/or zigmahornets and I want to stick with natural fiber cones.

TThe SIOs will be even better at 50 hours and should be all  the way there by 200, though it seems at 100 you'll be most of the way there.

Looking forward to the report on the whole thing, especially after the tweeter and crossover upgrades.

-- Jim