Graaf GM200 GM20 Modena OTL Quad ESL 63

Click pic to enlarge. Quad ESL-63 on stands; Graaf GM200 on stool, connected with Nordost Speaker Cables; above, pair of GM20 Modena Monoblocks with black coverings, next to which Marantz 10B Tuner; beneath Marantz is Luminous Audio Passive Control.

Virtual Home Visits (9): Quad ESL, Graaf OTL

The Perfect Gentleman
This photo came by accident. When Jules (Visit 8) sent his photo to me, he included this one, which briefly threw me off. It turned out to be a more recent picture of the home of dkyyu, which I had visited a few times before. dkyyu is a perfect gentleman and a generous man (come to think of it, don't you think the majority of audiophiles, of any nationality, are really nice people?). I took the liberty of using this photo, just to say hello to him! dkyyu is also a precious tea collector and an LP collector.

Researching this blog, I was surprised that I had actually recorded a visit to dkyyu more than 10 years ago!!! I forgot about it! It is still a good read, and relevant to this article! :-) That makes me happy. I have visited him after that, but did not write about it, so please say hello to LeeHC and big Lau for me too! I miss you all!

dkyyu's living room can be considered reasonably sized in HK. He is a die-hard vintage Quad ESL fan, owner of the iconic ESL-57 and ESL-63. There is a crazy gang of vintage ESL users in HK; some members even do DIY repairs (HK is very humid, and almost all ESL's go bad). Some of their exploits can be seen here (pics galore).

ESL users naturally gravitate to OTL (the theoretical high impedance matching thing). That is one of the reasons (but no the only one) why I have heard many Graaf's in HK. This Modena (home of the 3 i's of race cars) manufacturer is not well known in the US. This is understandable, as North American homes on the average are much larger and OTL, being a low-powered and impedance matching oddball, is a niche; and the US also has its own Atmasphere and Transcendent Sound. On the other hand, in places like the UK, Europe and Hong Kong, listening quarters are small and Graaf would be more suitable. In the HK market, any Graaf that shows up is lapped up quickly; in NA, I think it'd be like hunting for hen's teeth. Graaf's official websites have not been updated for a few years but can still be read (old one has more info, "new one" less so). If readers know if they are defunct or not, please let me know. Where are you, "Giacomo Bello" (come to think of it, can you email me?)?

OTL in General My own experience with OTL is summarized here in an Overview.

Graaf GM 20
Graaf's most commonly seen OTL amp is the GM20 (this review is probably by Ken Kessler of HiFi News). Employing 4 x 6C33, it puts out 20 watts. It is a great amp, and not just with ESL. Yes, I have heard it with vintage Quad ESL, like at dkyyu's place, to good effect. But, keep in mind, I understand what's good about ESL, but am not an exact fan of vintage ESL, as they image low and have no power envelope to speak of for this classical symphonic listener. In my opinion, for vintage ESL, elevation and addition of subwoofer is a must. I'd actually prefer my lowly low-level Martin Logan Source (here, and there are many after that pilot, just search; second-hand price is probably a few hundred dollars). But I notice that dkyyu now has a subwoofer! If my memory serves me, my previous visits were without, and that is a big step forward by my thinking! In terms of average,based on what I heard in HK, I actually prefer the sound of my friend relax173's Graaf + B and W Nautilus 804. So, OTL can work well with other lower impedance loudspeakers as well.

Graaf Modena Monoblocks 
These are special monoblock editions of the GM20, and highly coveted. The sound is excellent, just like the GM20, with a little more power. Should you be interested, this past sales ad has a lot of great pics.

Graaf GM 200
Judging by the looks and the "magic eye" tubes, dkyyu's ' "newest" acquisition, which I have not heard, is the GM 200, 10x the power of the GM20! This was reviewed by Ken Kessler in HiFi News and Stereophile. A whopping 42 tubes, and in ultra-hot sub-tropical (misnomer; I think the difference between sub- and tropical is disappearing) HK! While I admire the fanaticism, I cannot really take this to heart. I am sure it sounds great, but the energy cost! I'll take the GM20 myself, thank you. What I am saying is, no matter what the power, vintage ESL is highly limited in dynamics - there is a reason why SME's Alistair Richardosn employed stacked pairs! For me, the current Quad offerings (28' and 29' series) are more dynamic and suitable (though I shall still opt for Martin Logan).

Thank you Jules, and dkyyu! You both have enhanced my audio experience so much. I am grateful that I have you as friends.

Home Visit: Dahlquist DQ20 Totaldac Luminous Audio Volent

Left, DQ10; Right, DQ20.

Home Visit: Dahlquist DQ-20
Overview: DahlquistMy First Serious Stereo System
Yumcha Diary: 24-09-2016
Letter from NYC (56) 2016 (12)

Article finished in NYC. This article was long in the making because the appearance of DQ20 totally usurped order at my friend Jules' house, and I had to drastically alter the layout. Call it a labor of love for Dahlquist.

My old friend Jules is that rare breed, a truly experienced audiophile who has impeccable musical taste. As a result, his systems never sound less than good. Although I periodically visit him I seldom write him up (see here). His equipment has changed much recently (?mid-life crisis, :-p) and we paid him three visits, this article being about the first two (same equipment). The third visit shall be written up later (Technics SB-7000!).

Equipment (at the time):
CD transport: Orpheus Zero SE
DAC: Totaldac D1 Twelve
Preamp/Amp:
1. Luminous Audio Axiom 2 passive + Brinkmann Mono
2. Paracas Sierra + Krell KSA200
3. PSE SL + Krell KSA200
Speakers Visit 1: Volent VL3.5 (latest grey ceramic unit)
Speakers Visit 2: Dahlquist DQ-20

Pic of Saul Marantz and Jon Dahlquist. Click to enlarge. Note the Marantz 10B tuner, 7 preamp and 9 monoblocks.

Overview Dahlquist
Since my experience of Dahlquist is confined to the DQ10 and DQ20, it is stretching it a bit to call an overview. However, since 1) these two are Dahlquist flagships and most famous creations; 2) I have had intimate experience with two pairs of DQ10's, one of which I owned for a LONG time; and 3) I now have heard two pairs of DQ20's, I feel justified.

Dahlquist was formed by the great Saul Marantz after he sold his company to the Japanese, with young Jon Dahlquist on board. The DQ10 and the much later DQ20 have similar design philosophy, with only the woofer enclosed and all other drivers open-back. Dahlquist's approach was influential and likely inspired later designs like Alon. The DQ-10 visually is a dead-ringer for Quad ESL57, which I take to be a tribute to the latter's sonic purity. It is commonly held that at the time of DQ10, quality drivers were few and Jon Dahlquist had to make a lot of adjustments to make the drivers work together. The DQ20 had fewer drivers of likely better quality. Visually it is a taller DQ10. Both look and sound great to me.

DQ10 The DQ10 is one of the classic speakers of all time, and has made its way into many audio halls of fame (like this one in TAS). It even has a facebook of its own! The DQ10 has a long production history, with apparently quite a few changes of drivers and parts along the way. The net has many entries on it but given its nature things can be a little confusing.

My Road to DQ10 For the longest time I was not at all an audiophile. I bought my first humble stereo system in 1973  (for details of my audio beginnings, see here).  Around the late 70's I upgraded to the cheapest Pioneer separates, and although they were not too great either I kept the system for a long time. Gradually I came to realize my speakers were the limiting factor. I had a good friend in undergraduate school who started working after graduation and bought a nice system. It was SAE equalizer preamp/amp, a Thorens TT and most importantly, the Dahlquist DQ-10 (he also added the Dahlquist subwoofer later). He was (is) one of those friends who widens one's horizon. Hey, introducing me to Sibelius and Bruckner immeasurably enriched my life! Although I went on for four more years of school, I visited him quite often and listened to music together. The DQ10 impressed me greatly, and I lusted after it for many years. After I finished my specialty training and started making a better salary, I went shopping for a serious system.

One day I visited Stereo Exchange (when they had that cavernous basement of goodies - those were the days!) and was ecstatic when I saw the pair of DQ-10, waiting for me after all these years! I immediately bought them and also the Thorens TD-125MKII with an SME armboard (since I had, and still have, the 3009i arm). Then I went shopping for preamp/amp. I narrowed it down to the then well-reviewed entry level Adcom and B&K systems. I did a serious audition at a hifi store on 70th Street and Broadway (forgot the name) and finally decided on the warmer B and K ST140 with the entry level Pro5 preamp. These B and K's (and the contemporary Adcom too) still command a reasonable second-hand price!

Sound My friend's Pair As I realized later, my friend had a living room of tall ceiling and just the right size for his system.He had them against the wall, flanking the fireplace. The sound was warm, fluid and utterly musical. That I later assembled a system very similar to my friend's is testimony to its spell on me. My own pair Soon after I acquired my system I later moved into an apartment with a very large living room and (!)14 ft ceiling (it was previously a multi-tiered parking space) and I had the system against the wall. The sound was not as good as at my friend's. True, the midrange was splendid and it was very musical, but the top was a little shut in. Image was good but there was not much of a soundstage and everything was just a little diffuse. My suspicion that my 70 wpc amp was not up to the task (in this cavernous space) grew on me, and was confirmed much later on when a friend came over with his McIntosh MC-60 monoblocks, which totally opened up the sound. That taught me two things: 1) DQ-10 is power hungry; 2) 60 wpc of tube power is much more power than 70 wpc solid state. And - I became a tube person right then and never looked back. A few years later when I rented out my apartment and relocated I sold my pair of DQ-10's to a friend's photographer boyfriend (he instantly fell in love with the DQ10's when he attended one of my parties) and he enjoyed them with his rock and pop. The memory of all the precious time spent with these two pairs of DQ-10's is always somewhere on my mind. One more thing, I have heard few speakers with better mid bass and bass articulation.

DQ20 The DQ20 was issued 14 years after the DQ10. With more competing choices, it was never quite as well received as the DQ10, perhaps because the older loudspeaker sold too well and had many die-hard fans. I always feel the DQ20 never got its due. For a contemporary review see hifi-classic (unfortunately we do not know from which magazine).

Sound First Pair The first time I listened to the DQ20 was at a music lover's house (he was selling some records). He was not an audiophile but I instantly liked the sound, which bore no little resemblance to the DQ10, which I still had at the time. I have always felt the DQ20 deserves more attention than it had received. Second Pair Before I had even paid him the visit to hear the Volent loudspeakers Jules called me about a pair he saw in the (HK) second-hand forum review33. The asking price was very reasonable and I told him to grab it. As they say, the rest is history (see below).

Service/Parts/Upgrades Dahlquist went under a long time ago, although it was resurrected briefly by a Canadian company. However, the company regnar specializes in service and parts of Dahlquist products, including the DQ10/20. Since I do NOT find much that is wrong with the 10/20, I'd personally shy away from so-called "upgrades" that second-guess the designer.

Sonic Impressions:

• Dahlquist DQ20 I heard this on the second visit. Having heard the Volent by then I was astonished by the change the Dahlquist brought about. The music acquired a much greater vibrancy. Midrange was hard to fault and vocals came alive with great presence. Most noticeable were the great rhythm and pace and deep reaching and walking bass. Just loved it, no if's and's or but's. At today's price, it is a steal.

• Volent 3.5 During the first visit, for over 2 hours, we listened to a large number of recordings, and also alternated between various preamps and amps. The sound was good, but on the polite side. Now, I am not a great believer of mixing technologies, but the Volent, though not cheap at all, did a reasonable (but not perfect, as the bass was a little four-square) job of integrating the ribbon, ceramic and Ensemble/-like bass units. By itself, it is not bad. But compared to the Dahlquist heard not so long after, there was just no comparison - the Volent sounded like processed music, but the Dahlquist made a serious attempt at creating the presence of live music, and mostly succeeded!

• Totaldac This up-end version is highly rated on the net. During the first visit, I thought the sound was good, but I just did not get the hang of it. I wrote in the initial draft of this article: "...I wondered "how absolutely good is it? I don't know. I'd like to get my Sparkler S303 to match up one day...". During the second visit, with the Dahlquist DQ20 in place, I began to hear the character of non-oversampling, and to get it. Jules perceptively made the remark: "The Dahlquist DQ20 brought out more of the character of Totaldac."

• Luminous Audio Jules bought this after my friend icefox poisoned him. He loves it. It seems transparent and pretty nice and I'd like try it in my system one day.

Viva Dahlquist!