[PatOMalley]

Hey Jim,

Any issues with using Burson's discrete op-amp in the Bugle in the last output op-amp slot?
They claim it beats the OPA627 and AD825.

http://www.bursonaudio.com/Burson_HDAM_Module.htm

[hagtech]

Hard to say.  They give very little electrical information.  Other than just to say it will work anywhere. 

jh

[bluesky]

Hi Pat

I have undertaken a number of upgrades installing the burson opamps in a variety of different CD players.

To date the Burson opamps have provided a significant improvement and have replaced several different types of dual opamps.  One thing I have found is that Burson supplies their opamps with a single strand of small gauge copper wire (similar to Cat5e) for use as a ground and a few people have said they had hum problems.  I replaced the single strand with two strands of twisted wire and earthed it with the shortest length possible and this appears to have solved the hum problem with people who have reported this problem.

Should the opamp not be suitable I know that Burson promptly refunds the person, at least from my fairly limited experience I have to say.

Hope this helps,

Bluesky

Disclosure - I do installations of Burson Audio products (amongst others) but I am not part of their company.   

[PatOMalley]

thanks Bluesky, I will give it a try. The return policy saves the day.

[bluesky]

Hi Pat

Please double check with Burson first!  I don't sell their products I only put them in for people and don't have any control over their policies. 

Having said that though I have found Jack and Alex from Burson Audio to be beyond reproach with all my dealings with them and they have always bent over backwards for their customers from what I've seen to date.  I wouldn't blame if they didn't give a refund to someone who had soldered the opamp in rather than use some 8 pin sockets to ensure they work first.  So use some sockets and if all is well then solder them to the PCB as this provides a better connection.

Let us know how you find them!  Everyone I had done this upgrade for has described the difference as night and day and Nick Whetstone from TNT has also given a positive review.  I always try to be conservative with recommendations and allow others to provide opinions to help ensure the validity of comments.

Bluesky

[hagtech]

The BUGLE should be a good candidate for the Burson modules, as it doesn't demand too much from the opamps.  Just straight gain.  No unusual demands.  I'd expect them to operate just fine.  Only issue is one of battery life, if you're operating from the stock 9Vs.

jh

[PatOMalley]

I have the Bugle Pro w/ 15v power supply. U1 & U2 have soldered in OPA2134; I have a slot in U3 running OPA2888. The Burson will go in the U3 slot ... but I will solder them in if they are tip-top. I keep reading articles saying that that favor discrete over opamp and I expect they if the work they will work really really well.

I am using the stock case from digikey so there should be plenty of room. I may fit some copper as a shield between power supply and Bugle board, if need be, or do you think that is far enough away Jim? I do not have any hum now.

[hagtech]

Copper shielding will probably not make any difference.  If there is coupling, it will be magnetic, which you cannot shield - you have to "channel" or conduct it.  But that is difficult.  Much easier to just use distance.

Distance and time are the most powerful forces in the universe (except perhaps faith).  Use them wisely.  The strongest of anything will always succumb to time.

jh

[PatOMalley]

I installed the Burson the other day but I don't think it was an improvement. First I want to say that this post is in no way a bash of the Burson opamp as the company is outstanding in support. Shipping took longer than usual and I was worried and Burson made offers of support that I thought went beyond the call. The opamp just did not work out in my installation.

Otherwise the install of the Burson as opposed to the OPA2888p that was in there made the sound thinner, less bass, no magic. Burson says that their opamp draws more power than standard opamps but using the 15V power supply should do the trick. I put the OPA2888P back in and the sound became full bodied.

[Brinkman]

Pat,

Did you find out anything as to whether having the two OPA2134s in the first two positions affects the performance of the op amp in the third? I noticed you asked this in a prior post here and am curious myself as to the answer.

Best,
Benjamin

[PatOMalley]

Jim says that is AOK to have those opamps there. Another offboard user syas he aggrees that he does not like the sound of the Burson in the Bugle as well, so maybe it is just this circuit that does not play well with the Burson. I only know practical stuff. I am still going to try their opamps in my NAD CDP in the future. They are a great company to deal with, very supportive, so I highly reccomend them in general.

[Brinkman]

I suppose my objective with the Bugle is to produce a rather balanced, neutral sound.
Having built an ST70 tube amp from a kit, I've found that the amplifier excels wonderfully in the midrange but is not well-suited for extension at the ends. I've heard this is not an uncommon limitation for tube gear, so rather than having a series of components compensating for the weaknesses of each other, I want to get the most uncolored, unbiased and linear signal from my phono-pre that is feasible (for the record, I am on the path to a SS biamping via active crossover to remedy my low-end requirements).
Some Op Amps I've considered for any/all Bugle slots are:
OPA2134 (stock)
AD826,
AD827
AD843 (adapter needed)
LM4562
OPA637 (adapter needed)
OPA2228
Burson Discreet

Any comments/experience you may have had with the above (aside from the Burson) is welcomed.

Best,
Benjamin

[shep]

I had the opa2134 on my cdp as stock, tried the OPA627 and now the LM4562. The latter is still burning in but sounds very organic, very tactile. I like it a lot. Opamps are like tubes; very system dependant. It's very hard to get a consensus on what sounds best and where. (and never mind why!)

[PatOMalley]

So far I like the 2888 best. Since the Burson's did not work out for me I am going to try AD825's. Some people report that these beat the OPA627's.

The deal with the 2888's is that they are smooth, warm, full bodied, verve but not big on detail. They do this organic whole thing that is hard to beat.  Probably the 627s do beat it but I have read that the AD825 are even better.

[Brinkman]

I'm most interested in the LM4562... I believe the OPA627 and OPA637 are closely related (sound signature-wise), as are the AD825 and the AD826/827. Is this true?

[shep]

Me? I don't know. Opamps are part of the black arts. I just do what people tell me sounds best! (the ultimate audiophile wimp) I can tell you that the LM4562's sounds absolutely amazing...and they are not even run in yet fully. They seem to change in 10hr increments. No doubt next month there will be something even better...sigh.

[Brinkman]

Me? I don't know. Opamps are part of the black arts. I just do what people tell me sounds best! (the ultimate audiophile wimp)

Considering the financial strain and "alone time" required to purchase and audition all contenders for "best" Op Amp, I'd say you're (we're) more the norm when it comes to amateur-level audiophilia. At least we're humble enough to be honest; I've lurked long enough to encounter people making sweeping generalizations on forums, and upon being pressed on their reasoning, sheepishly admit that they haven't tried out said op amp/tube/capacitor/whatever but are merely repeating what "sources told them".
As expensive a hobby this is, I can at least understand this temptation. Though I would never condone flat-out disingenuity.

As for the LM4562, I'm definetely going to order three. I may also order a "reputable" Burr Brown and Analogue Designs Op Amp for comparison & contrast. Kinda a shame the Burson Op Amp discreet dual is so spendy; I actually overspent my credit limit (without knowing it) on that one. Perhaps I can use it in a crossover...

Best,
Benjamin

[shep]

I'm not modest by nature but this forum being big and full of brains (and brawn)... man would be a fool to pretend anything and get called out  aa By the way, you can order samples of the LM4562 for free from their site, after filling in a form and having an address or web site that looks vaguely professional. At least this was the case as of a week ago. Specify LM4562na. Takes time though. (as does the burn-in... 100hrs apparently) While you're at it, try also the
AD8599, which apparently is as good as the LM but has a different sonic signature. (self-interest at work...I want to know how it sounds!)

[mdelrossi]

I've got 3 samples of LM4562na coming from National Semi. I was wondering if it makes sense to put all 3 in all 3 sockets or is it just the 3rd socket where it makes a difference?
If it's just the 3rd then i've got 2 LM4562's to play with
thanks
mdr